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Montazeri SM, Kalogerakis N, Kolliopoulos G. Effect of chemical species and temperature on the stability of air nanobubbles. Sci Rep 2023; 13:16716. [PMID: 37794127 PMCID: PMC10550960 DOI: 10.1038/s41598-023-43803-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Accepted: 09/28/2023] [Indexed: 10/06/2023] Open
Abstract
The colloidal stability of air nanobubbles (NBs) was studied at different temperatures (0-30 °C) and in the presence of sulfates, typically found in mining effluents, in a wide range of Na2SO4 concentrations (0.001 to 1 M), along with the effect of surfactants (sodium dodecyl sulfate), chloride salts (NaCl), and acid/base reagents at a pH range from 4 to 9. Using a nanobubble generator based on hydrodynamic cavitation, 1.2 × 108 bubbles/mL with a typical radius of 84.66 ± 7.88 nm were generated in deionized water. Multiple evidence is provided to prove their presence in suspension, including the Tyndall effect, dynamic light scattering, and nanoparticle size analysis. Zeta potential measurements revealed that NBs are negatively charged even after two months (from - 19.48 ± 1.89 to - 10.13 ± 1.71 mV), suggesting that their stability is due to the negative charge on their surface. NBs were found to be more stable in alkaline solutions compared to acidic ones. Further, low amounts of both chloride and sulfate dissolved salts led to a reduction of the size of NBs. However, when high amounts of dissolved salts are present, NBs are more likely to coalesce, and their size to be increased. Finally, the investigation of the stability of air NBs at low temperatures revealed a non-monotonic relationship between temperature and NBs upon considering water self-ionization and ion mobility. This research aims to open a new frontier towards the application of the highly innovative NBs technology on the treatment of mining, mineral, and metal processing effluents, which are challenging aqueous solutions containing chloride and sulfate species.
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Affiliation(s)
- Seyed Mohammad Montazeri
- Department of Mining, Metallurgical, and Materials Engineering, Université Laval, Québec, QC, G1V 0A6, Canada
| | - Nicolas Kalogerakis
- School of Chemical and Environmental Engineering, Technical University of Crete, 73100, Chania, Greece
| | - Georgios Kolliopoulos
- Department of Mining, Metallurgical, and Materials Engineering, Université Laval, Québec, QC, G1V 0A6, Canada.
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2
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Kosmulski M. The pH dependent surface charging and points of zero charge. X. Update. Adv Colloid Interface Sci 2023; 319:102973. [PMID: 37573830 DOI: 10.1016/j.cis.2023.102973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2023] [Revised: 07/31/2023] [Accepted: 08/01/2023] [Indexed: 08/15/2023]
Abstract
Surfaces are often characterized by their points of zero charge (PZC) and isoelectric points (IEP). Different authors use these terms for different quantities, which may be equal to the actual PZC under certain conditions. Several popular methods lead to results which are inappropriately termed PZC. This present review is limited to zero-points obtained in the presence of inert electrolytes (halides, nitrates, and perchlorates of the 1st group metals). IEP are reported for all kinds of materials. PZC of metal oxides obtained as common intersection points of potentiometric curves for 3 or more ionic strengths (or by means of equivalent methods) are also reported, while the apparent PZC obtained by mass titration, pH-drift method, etc. are deliberately neglected. The results published in the recent publications and older results overlooked in the previous compilations by the same author are reported. The PZC/IEP are accompanied by information on the temperature and on the nature and concentration of supporting electrolyte (if available). The references to previous reviews by the same author allow to compare the newest results with the PZC/IEP of similar materials from the older literature.
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Affiliation(s)
- Marek Kosmulski
- Lublin University of Technology, Nadbystrzycka 38, PL-20618 Lublin, Poland.
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3
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Chereches EI, Minea AA. Experiments on the Electrical Conductivity of PEG 400 Nanocolloids Enhanced with Two Oxide Nanoparticles. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:nano13091555. [PMID: 37177100 PMCID: PMC10180904 DOI: 10.3390/nano13091555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2023] [Revised: 04/29/2023] [Accepted: 05/04/2023] [Indexed: 05/15/2023]
Abstract
This paper aims to provide some insights into the pH and electrical conductivity of two classes of nanocolloids with PEG 400 as the base fluid. Thus, nanoparticles of two oxides-MgO and TiO2-were added to the base fluid in 5 mass concentrations in the range 0.25-2.5 %wt. The stability was evaluated in terms of pH at ambient temperature, while the electrical conductivity was discussed at both ambient temperature and up to 333.15 K. The electrical conductivity of PEG 400 was previously discussed by this group, while the behavior of the new nanocolloids was debated in terms of the state of the art. More precisely, the influence of MgO increases electrical conductivity, and an enhancement of up to 48% for 0.25% MgO was found, while the influence of TiO2 nanoparticles was found to be in similar ranges. In conclusion, electrical conductivity varies with temperature and the addition of nanoparticles to the base fluid, although the mechanisms that are driving the nanoparticle type and concentration influence are not yet entirely assumed in the available literature.
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Affiliation(s)
- Elena Ionela Chereches
- Faculty of Materials Science and Engineering, Technical University "Gheorghe Asachi" of Iasi, Bd. D. Mangeron No. 63, 700050 Iasi, Romania
| | - Alina Adriana Minea
- Faculty of Materials Science and Engineering, Technical University "Gheorghe Asachi" of Iasi, Bd. D. Mangeron No. 63, 700050 Iasi, Romania
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4
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Rayaroth MP, Marchel M, Boczkaj G. Advanced oxidation processes for the removal of mono and polycyclic aromatic hydrocarbons - A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 857:159043. [PMID: 36174692 DOI: 10.1016/j.scitotenv.2022.159043] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 09/16/2022] [Accepted: 09/22/2022] [Indexed: 06/16/2023]
Abstract
Aromatic hydrocarbons (AHs) are toxic environmental contaminants presented in most of the environmental matrices. Advanced oxidation processes (AOPs) for the removal of AHs in the account of complete mineralization from various environmental matrices have been reviewed in this paper. An in-depth discussion on various AOPs for mono (BTEX) and polyaromatic hydrocarbons (PAHs) and their derivatives is presented. Most of the AOPs were effective in the removal of AHs from the aquatic environment. A comparative study on the degradation of various AHs revealed that the oxidation of the AHs is strongly dependent on the number of aromatic rings and the functional groups attached to the ring. The formation of halogenated and nitrated derivatives of AHs in the real contaminated water containing chloride, nitrite, and nitrate ions seems to be a challenge in using the AOPs in real systems. The phenolic compounds, quinone, alcohols, and aliphatic acids are the important byproducts formed during the oxidation of AHs, initiated by the attack of reactive oxygen species (ROS) on their electron-rich center. In conclusion, AOPs are the adaptable method for the removal of AHs from different environmental matrices. The persulfate-based AOPs were applied in the soil phase removal as an in situ chemical oxidation of AHs. Moreover, the combination of AOPs will be a conclusive solution to avoid or minimize unexpected or other toxic intermediate products and to obtain rapid oxidation of AHs.
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Affiliation(s)
- Manoj P Rayaroth
- Gdańsk University of Technology, Faculty of Chemistry, Department of Process Engineering and Chemical Technology, 80-233 Gdańsk, G. Narutowicza 11/12 Str, Poland; GREMI, UMR 7344, Université d'Orléans, CNRS, 45067 Orléans, France
| | - Mateusz Marchel
- Gdańsk University of Technology, Faculty of Chemistry, Department of Process Engineering and Chemical Technology, 80-233 Gdańsk, G. Narutowicza 11/12 Str, Poland
| | - Grzegorz Boczkaj
- Gdańsk University of Technology, Faculty of Civil and Environmental Engineering, Department of Sanitary Engineering, 80-233 Gdańsk, G. Narutowicza 11/12 Str, Poland; EkoTech Center, Gdansk University of Technology, G. Narutowicza St. 11/12, 80-233 Gdansk, Poland.
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Elkartehi ME, Mahmoud R, Shehata N, Farghali A, Gamil S, Zaher A. LDH Nanocubes Synthesized with Zeolite Templates and Their High Performance as Adsorbents. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:3315. [PMID: 34947664 PMCID: PMC8708268 DOI: 10.3390/nano11123315] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 11/15/2021] [Accepted: 11/17/2021] [Indexed: 11/17/2022]
Abstract
In this work, the efficiency of the adsorptive removal of the organic cationic dye methylene blue (MB) from polluted water was examined using three materials: natural clay (zeolite), Zn-Fe layered double hydroxide (LDH), and zeolite/LDH composite. These materials were characterized via X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, high-resolution transmission electron microscopy (HRTEM), energy dispersive X-ray (EDX) diffraction (XRF), low-temperature N2 adsorption, pore volume and average pore size distribution and field emission scanning electron microscopy (FE-SEM). The properties of the applied nanomaterials regarding the adsorption of MB were investigated by determining various experimental parameters, such as the contact time, initial dye concentration, and solution pH. In addition, the adsorption isotherm model was estimated using the Langmuir, Freundlich, and Langmuir-Freundlich isotherm models. The Langmuir model was the best-fitting for all applied nanomaterials. In addition, the kinetics were analyzed by using pseudo-first-order, pseudo-second-order, and intraparticle diffusion models, and the pseudo-second-order model was an apparent fit for all three applied nanomaterials. The maximum Adsorption capacity toward MB obtained from the materials was in the order zeolite/LDH composite > zeolites > Zn-Fe LDH. Thus, the zeolite/LDH composite is an excellent adsorbent for the removal of MB from polluted water.
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Affiliation(s)
- Moftah Essa Elkartehi
- Department of Environmental Science and Industrial Development, Faculty of Postgraduate Studies for Advanced Sciences, Beni-Suef University, Beni-Suef 62511, Egypt; (M.E.E.); (N.S.)
| | - Rehab Mahmoud
- Department of Chemistry, Faculty of Science, Beni-Suef University, Beni-Suef 62511, Egypt
| | - Nabila Shehata
- Department of Environmental Science and Industrial Development, Faculty of Postgraduate Studies for Advanced Sciences, Beni-Suef University, Beni-Suef 62511, Egypt; (M.E.E.); (N.S.)
| | - Ahmed Farghali
- Materials Science and Nanotechnology Department, Faculty of Postgraduate Studies for Advanced Sciences, Beni-Suef University, Beni-Suef 62511, Egypt; (A.F.); (S.G.)
| | - Shimaa Gamil
- Materials Science and Nanotechnology Department, Faculty of Postgraduate Studies for Advanced Sciences, Beni-Suef University, Beni-Suef 62511, Egypt; (A.F.); (S.G.)
| | - Amal Zaher
- Department of Environmental Science and Industrial Development, Faculty of Postgraduate Studies for Advanced Sciences, Beni-Suef University, Beni-Suef 62511, Egypt; (M.E.E.); (N.S.)
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6
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Abdel-Rafei MK, Thabet NM, Abdel Maksoud MIA, Abd Elkodous M, Kawamura G, Matsuda A, Ashour AH, El-Batal AI, El-Sayyad GS. Influence of Ce 3+ Substitution on Antimicrobial and Antibiofilm Properties of ZnCe xFe 2-xO 4 Nanoparticles (X = 0.0, 0.02, 0.04, 0.06, and 0.08) Conjugated with Ebselen and Its Role Subsidised with γ-Radiation in Mitigating Human TNBC and Colorectal Adenocarcinoma Proliferation In Vitro. Int J Mol Sci 2021; 22:10171. [PMID: 34576334 PMCID: PMC8466506 DOI: 10.3390/ijms221810171] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 09/15/2021] [Accepted: 09/16/2021] [Indexed: 01/13/2023] Open
Abstract
Cancers are a major challenge to health worldwide. Spinel ferrites have attracted attention due to their broad theranostic applications. This study aimed at investigating the antimicrobial, antibiofilm, and anticancer activities of ebselen (Eb) and cerium-nanoparticles (Ce-NPs) in the form of ZnCexFe2-XO4 on human breast and colon cancer cell lines. Bioassays of the cytotoxic concentrations of Eb and ZnCexFe2-XO4, oxidative stress and inflammatory milieu, autophagy, apoptosis, related signalling effectors, the distribution of cells through the cell-cycle phases, and the percentage of cells with apoptosis were evaluated in cancer cell lines. Additionally, the antimicrobial and antibiofilm potential have been investigated against different pathogenic microbes. The ZOI, and MIC results indicated that ZnCexFe2-XO4; X = 0.06 specimen reduced the activity of a wide range of bacteria and unicellular fungi at low concentration including P. aeruginosa (9.5 mm; 6.250 µg/mL), S. aureus (13.2 mm; 0.390 µg/mL), and Candida albicans (13.5 mm; 0.195 µg/mL). Reaction mechanism determination indicated that after ZnCexFe2-xO4; X = 0.06 treatment, morphological differences in S.aureus were apparent with complete lysis of bacterial cells, a concomitant decrease in the viable number, and the growth of biofilm was inhibited. The combination of Eb with ZFO or ZnCexFe2-XO4 with γ-radiation exposure showed marked anti-proliferative efficacy in both cell lines, through modulating the oxidant/antioxidant machinery imbalance, restoring the fine-tuning of redox status, and promoting an anti-inflammatory milieu to prevent cancer progression, which may be a valuable therapeutic approach to cancer therapy and as a promising antimicrobial agent to reduce the pathogenic potential of the invading microbes.
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Affiliation(s)
- Mohamed K. Abdel-Rafei
- Radiation Biology Department, National Center for Radiation Research and Technology (NCRRT), Egyptian Atomic Energy Authority (EAEA), Cairo 11787, Egypt;
| | - Noura M. Thabet
- Radiation Biology Department, National Center for Radiation Research and Technology (NCRRT), Egyptian Atomic Energy Authority (EAEA), Cairo 11787, Egypt;
| | - M. I. A. Abdel Maksoud
- Materials Science Lab., Radiation Physics Department, National Center for Radiation Research and Technology (NCRRT), Egyptian Atomic Energy Authority (EAEA), Cairo 11787, Egypt; (M.I.A.A.M.); (A.H.A.)
| | - M. Abd Elkodous
- Department of Electrical and Electronic Information Engineering, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku-cho, Toyohashi 441-8580, Aichi, Japan; (M.A.E.); (G.K.)
| | - Go Kawamura
- Department of Electrical and Electronic Information Engineering, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku-cho, Toyohashi 441-8580, Aichi, Japan; (M.A.E.); (G.K.)
| | - Atsunori Matsuda
- Department of Electrical and Electronic Information Engineering, Toyohashi University of Technology, 1-1 Hibarigaoka, Tempaku-cho, Toyohashi 441-8580, Aichi, Japan; (M.A.E.); (G.K.)
| | - A. H. Ashour
- Materials Science Lab., Radiation Physics Department, National Center for Radiation Research and Technology (NCRRT), Egyptian Atomic Energy Authority (EAEA), Cairo 11787, Egypt; (M.I.A.A.M.); (A.H.A.)
| | - Ahmed I. El-Batal
- Drug Microbiology Lab., Drug Radiation Research Department, National Center for Radiation Research and Technology (NCRRT), Egyptian Atomic Energy Authority (EAEA), Cairo 11787, Egypt; (A.I.E.-B.); (G.S.E.-S.)
| | - Gharieb S. El-Sayyad
- Drug Microbiology Lab., Drug Radiation Research Department, National Center for Radiation Research and Technology (NCRRT), Egyptian Atomic Energy Authority (EAEA), Cairo 11787, Egypt; (A.I.E.-B.); (G.S.E.-S.)
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7
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Wu S, Gaillard JF, Gray KA. The impacts of metal-based engineered nanomaterial mixtures on microbial systems: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 780:146496. [PMID: 34030287 DOI: 10.1016/j.scitotenv.2021.146496] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 02/23/2021] [Accepted: 03/11/2021] [Indexed: 05/24/2023]
Abstract
The last decade has witnessed tremendous growth in the commercial use of metal-based engineered nanomaterials (ENMs) for a wide range of products and processes. Consequently, direct and indirect release into environmental systems may no longer be considered negligible or insignificant. Yet, there is an active debate as to whether there are real risks to human or ecological health with environmental exposure to ENMs. Previous research has focused primarily on the acute effects of individual ENMs using pure cultures under controlled laboratory environments, which may not accurately reveal the ecological impacts of ENMs under real environmental conditions. The goal of this review is to assess our current understanding of ENM effects as we move from exposure of single to multiple ENMs or microbial species. For instance, are ENMs' impacts on microbial communities predicted by their intrinsic physical or chemical characteristics or their effects on single microbial populations; how do chronic ENM interactions compare to acute toxicity; does behavior under simplified laboratory conditions reflect that in environmental media; finally, is biological stress modified by interactions in ENM mixtures relative to that of individual ENM? This review summarizes key findings and our evolving understanding of the ecological effects of ENMs under complex environmental conditions on microbial systems, identifies the gaps in our current knowledge, and indicates the direction of future research.
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Affiliation(s)
- Shushan Wu
- Department of Civil and Environmental Engineering, Northwestern University, USA.
| | | | - Kimberly A Gray
- Department of Civil and Environmental Engineering, Northwestern University, USA.
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8
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El-Shazly AN, El-Sayyad GS, Hegazy AH, Hamza MA, Fathy RM, El Shenawy ET, Allam NK. Superior visible light antimicrobial performance of facet engineered cobalt doped TiO 2 mesocrystals in pathogenic bacterium and fungi. Sci Rep 2021; 11:5609. [PMID: 33692424 PMCID: PMC7946932 DOI: 10.1038/s41598-021-84989-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 02/24/2021] [Indexed: 01/31/2023] Open
Abstract
Pristine and Co-doped TiO2 mesocrystals have been synthesized via a simple sol-gel method and their antimicrobial activity has been investigated. The antimicrobial performance was evaluated in terms of zone of inhibition, minimum inhibitory concentration (MIC), antibiofilm activity, and effect of UV illumination in liquid media. The Co-doped TiO2 mesocrystals showed very promising MIC of 0.390 μg/mL and 0.781 μg/mL for P. mirabilis and P. mirabilis, respectively. Additionally, the material showed an MIC of 12.5 μg/mL against C. albicans, suggesting its use as antifungal agent. Upon the addition of 10.0 µg/mL of Co-doped TiO2 mesocrystals, the biofilm inhibition% reaches 84.43% for P. aeruginosa, 78.58% for P. mirabilis, and 77.81% for S. typhi, which can be ascribed to the created active oxygen species that decompose the tested microbial cells upon illumination. Thus the fabricated Co-doped TiO2 mesocrystals exhibit sufficient antimicrobial features under visible light, qualifying them for use as antimicrobial agents against pathogenic bacteria and fungi and subsequently inhibit their hazardous effects.
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Affiliation(s)
- Ayat N El-Shazly
- Energy Materials Laboratory, School of Sciences and Engineering, The American University in Cairo, New Cairo, 11835, Egypt
- Central Metallurgical Research and Development Institute, Helwan, P.O. Box 87, Cairo, Egypt
| | - Gharieb S El-Sayyad
- Drug Microbiology Lab., Drug Radiation Research Department, National Center for Radiation Research and Technology (NCRRT), Egyptian Atomic Energy Authority (EAEA), Cairo, Egypt
| | - Aiat H Hegazy
- Solar Energy Department, National Research Centre, Giza, Dokki, Egypt
| | - Mahmoud A Hamza
- Chemistry Department, Faculty of Science, Ain Shams University, Abbassia, Cairo, Egypt
| | - Rasha M Fathy
- Drug Microbiology Lab., Drug Radiation Research Department, National Center for Radiation Research and Technology (NCRRT), Egyptian Atomic Energy Authority (EAEA), Cairo, Egypt
| | - E T El Shenawy
- Solar Energy Department, National Research Centre, Giza, Dokki, Egypt
| | - Nageh K Allam
- Energy Materials Laboratory, School of Sciences and Engineering, The American University in Cairo, New Cairo, 11835, Egypt.
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Li K, Hanpei Y, Lina W, Siqi C, Ruichen Z, Junming W, Xiaona L. Facile integration of FeS and titanate nanotubes for efficient removal of total Cr from aqueous solution: Synergy in simultaneous reduction of Cr(VI) and adsorption of Cr(III). JOURNAL OF HAZARDOUS MATERIALS 2020; 398:122834. [PMID: 32512438 DOI: 10.1016/j.jhazmat.2020.122834] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Revised: 04/06/2020] [Accepted: 05/03/2020] [Indexed: 06/11/2023]
Abstract
In this study, a novel composite composed of iron monosulfide nanoparticles (FeS NPs) and titanate nanotubes (TNTs) was hydrothermally synthesized. Characterizations revealed the encapsulation and homogenous dispersion of FeS NPs into the interlayers of TNTs. Significant performance in removal of aqueous total Cr was acquired by efficient conversion of Cr(VI) to Cr(III) on FeS and simultaneous adsorption of Cr(III) on TNTs. Moreover, the high activity of FeS-TNTs in reduction of Cr(VI) can maintain at high oxicity or alkalinity of its solution. The synergistic effect between FeS and TNTs was derived from sheltering of FeS NPs from their self-aggregation, O2-oxidation and the affinity of Cr(III) to TNTs. The unique properties, e.g. the solid acidity, the hollow and interlayered configuration of TNTs played important roles in high activity, good stability and reusability of FeS-TNTs.
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Affiliation(s)
- Kang Li
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China
| | - Yang Hanpei
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China.
| | - Wang Lina
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China
| | - Chai Siqi
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China
| | - Zhang Ruichen
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China
| | - Wu Junming
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China
| | - Liu Xiaona
- College of Environmental Science and Engineering, Taiyuan University of Technology, Jinzhong, Shanxi, 030600, China.
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Frungieri G, Babler MU, Vanni M. Shear-Induced Heteroaggregation of Oppositely Charged Colloidal Particles. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:10739-10749. [PMID: 32814425 PMCID: PMC8011919 DOI: 10.1021/acs.langmuir.0c01536] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
This paper investigates numerically the shear-induced aggregation of mixed populations of colloidal particles leading to the formation of clusters. Suspensions with different amounts of positively and negatively charged colloidal particles are simulated. To resolve the aggregation kinetics and structural properties of the formed clusters, we resort to a mixed deterministic-stochastic simulation method. The method is built on a combination of a Monte Carlo algorithm to sample a statistically expected sequence of encounter events between the suspended particles and a discrete element method built in the framework of Stokesian dynamics to simulate the encounters in a fully predictive manner. Results reveal a strong influence of the composition of the population on both the aggregation kinetics and the aggregate structure. In particular, we observe a size-stabilization phenomenon taking place in the suspension when the relative concentration of the majority particles lies in the range 80-85%; i.e., starting from primary particles, after a short growth period, we observed a cessation of aggregation. Inspection of the aggregate morphology shows that the formed clusters are composed of few minority particles placed in the inner region, while the aggregate surface is covered by majority particles, acting to provide a shielding effect against further growth.
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Affiliation(s)
- Graziano Frungieri
- Department of Applied
Science and Technology, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Turin, Italy
| | - Matthaus U. Babler
- Department of Chemical Engineering, KTH
Royal Institute of Technology, Teknikringen 42, SE-10044 Stockholm, Sweden
| | - Marco Vanni
- Department of Applied
Science and Technology, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Turin, Italy
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11
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Quiroga-Flores R, Noshad A, Wallenberg R, Önnby L. Adsorption of cadmium by a high-capacity adsorbent composed of silicate-titanate nanotubes embedded in hydrogel chitosan beads. ENVIRONMENTAL TECHNOLOGY 2020; 41:3043-3054. [PMID: 30892147 DOI: 10.1080/09593330.2019.1596167] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
In this study, we developed a nanoparticle-based mesoporous composite that consisted of silicate-titanate nanotubes (STNTs) supported in hydrogel chitosan beads (STNTs-Ch beads) and was studied for Cd2+ adsorption. By using Fourier-transform infrared spectroscopy, transmission and scanning electron microscopy coupled to an energy-dispersive X-ray spectrometer, we could determine that the hollow STNTs were highly dispersed in the walls of the hollow beads. The dispersion was attributed to the effect of pH when the composite was prepared and we observed a non-interaction between STNTs and chitosan. The adsorption studies of Cd2+ showed that the kinetic rate (k 2) increased 3-fold and that the diffusion rate (K d) increased 2-fold after the embedment. Moreover, the maximum capacity of adsorption of STNTs-Ch beads was 2.3 times higher than that of STNTs alone. The treatment of a synthetic Cd2+ solution and a real leachate in continuous mode showed two phases in which it was observed higher removed fractions of transition metal ions (Cd2+, Co2+, Ni2+, Zn2+ and Cu2+) and the post-transition metal ion Pb2+, in comparison to the removed fractions of alkali and alkali-earth metal ions (Ca2+, K+, Mg2+). The composite was successfully reused four times when adsorbing Cd2+, saving three times the needed amounts of TiO2, SiO2 and chitosan for the production of the material. This composite was produced in a simple way and shows the potential for wastewater treatment.
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Affiliation(s)
- Roxana Quiroga-Flores
- Division of Biotechnology, Department of Chemistry, Lund University, Lund, Sweden
- Instituto de Investigaciones Fármaco Bioquímicas, Universidad Mayor de San Andrés, La Paz, Bolivia
| | - Asma Noshad
- Centre for Analysis and Synthesis, Department of Chemistry, Lund University, Lund, Sweden
| | - Reine Wallenberg
- Centre for Analysis and Synthesis, Department of Chemistry, Lund University, Lund, Sweden
- National Centre for High Resolution Electron Microscopy, Lund University, Lund, Sweden
| | - Linda Önnby
- Centre for Analysis and Synthesis, Department of Chemistry, Lund University, Lund, Sweden
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12
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Li H, Li S, Cao X, Sun W. Comparing the effects of different types of inorganic nanoparticles on 17β-estradiol adsorption by graphene oxide. ENVIRONMENTAL RESEARCH 2020; 187:109656. [PMID: 32464447 DOI: 10.1016/j.envres.2020.109656] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 05/10/2020] [Accepted: 05/10/2020] [Indexed: 06/11/2023]
Abstract
This study compared the effects of five types of inorganic nanoparticles (INPs) on the 17β-estradiol (E2) adsorption to graphene oxide (GO). The results showed that INPs increased the equilibrium time for the adsorption of E2 to GO. Higher Brunauer-Emmett-Teller (BET) surface area of INPs resulted in lower diffusion rate of E2, and thus the adsorption rate constant (k2) calculated from pseudo-second-order kinetic model negatively correlated with the BET surface area of INPs (p = 0.037). In addition, INPs decreased the adsorption amount of E2 to GO, and the inhibition effects declined in the order of Al2O3 > ZnO > TiO2 > SiO2 > Fe2O3. This is determined by the interactions between GO and INPs. The positively charged ZnO and Al2O3 strongly heteroaggregate with GO via electrostatic attraction, and then significantly inhibited E2 adsorption to GO. In contrast, the homoaggregation of GO was superior to its heteroaggregation with negatively charged SiO2 and TiO2, and then lower inhibition of E2 adsorption to GO was induced. Fe2O3 with less negative charge (-8.48 mV) led to the lowest inhibition effect on E2 adsorption to GO because of its preferable homoaggregation. The results were further confirmed by Derjaguin-Landau-Verwey-Overbeek calculation, transmission electron microscopy, and sedimentation experiments. This study revealed how the properties of INPs influence their effects on the adsorption of E2 by GO, and the findings are critical to understand the behavior and fate of GO and pollutants in natural aquatic environment.
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Affiliation(s)
- Huimin Li
- College of Environmental Sciences and Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing, 100871, China
| | - Si Li
- Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation, College of Resources and Environmental Sciences, China Agricultural University, Beijing, 100193, China
| | - Xiaoqiang Cao
- College of Chemical and Environmental Engineering, Shandong University of Science and Technology, Qingdao, Shandong, 266590, China
| | - Weiling Sun
- College of Environmental Sciences and Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing, 100871, China.
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13
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Photocatalytic removal of airborne indoor pollutants by IR illuminated silver coated TiO2 catalyst: Advantage of one-dimensional TiO2 nanostructures in IR active photocatalysis. Colloids Surf A Physicochem Eng Asp 2020. [DOI: 10.1016/j.colsurfa.2020.124509] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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14
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Monteiro WF, Vieira MO, Laschuk EF, Livotto PR, Einloft SM, de Souza MO, Ligabue RA. Experimental-theoretical study of the epoxide structures effect on the CO2 conversion to cyclic carbonates catalyzed by hybrid titanate nanostructures. J CO2 UTIL 2020. [DOI: 10.1016/j.jcou.2019.11.024] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
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15
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Zheng M, Ji H, Duan J, Dang C, Chen X, Liu W. Efficient adsorption of europium (III) and uranium (VI) by titanate nanorings: Insights into radioactive metal species. ENVIRONMENTAL SCIENCE AND ECOTECHNOLOGY 2020; 2:100031. [PMID: 36160918 PMCID: PMC9488033 DOI: 10.1016/j.ese.2020.100031] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2020] [Revised: 04/23/2020] [Accepted: 04/24/2020] [Indexed: 06/12/2023]
Abstract
Radioactive wastewater containing high concentration of radionuclides poses severe threats to ecosystem and human health, so efficient removal of these toxic heavy metals is urgently needed. Titanate nanomaterials have been demonstrated good adsorbents for heavy metals due to ion exchange property. In this study, titanate nanorings (TNRs) were synthesized using the facile hydrothermal-cooling method. The TNRs were composed of sodium trititanate, with a chemical formula of Na0.66H1.34Ti3O7•0.27H2O and a Na content of 2.38 mmol/g. The TNRs demonstrated sufficient adsorption performance to radionuclides europium (Eu) and uranium (U) ions. Specifically, even at a high initial concentration of 50 mg/L, 86.5% and 92.6% of the two metal ions can be rapidly adsorbed by the TNRs within 5 min, and equilibrium was reached within 60 min at pH 5. The maximum adsorption capacity (Q max) obtained by the Langmuir isotherm model was 115.3 mg/g for Eu(III) and 282.5 mg/g for uranium U(VI) at pH 5, respectively. The adsorption capacities of the two metals under various water chemical conditions were highly related to their species. Ion exchange between metal cations and Na+ in the TNR interlayers was the dominant adsorption mechanism, and adsorption of U(VI) was more complicated because of the co-existence of various uranyl (UO2 2+) and uranyl-hydroxyl species. The spent TNRs were effectively regenerated through an acid-base or ethylenediamine tetraacetic acid (EDTA) treatment and reused. Considering the large adsorption capacity and quick kinetic, TNRs are promising materials to remove radionuclides in environmental purification applications, especially emergent treatment of leaked radionuclides.
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Affiliation(s)
- Maosheng Zheng
- The Key Laboratory of Water and Sediment Sciences, Ministry of Education, College of Environmental Sciences and Engineering, Peking University, Beijing, 100871, China
- The Key Laboratory of Resources and Environmental Systems Optimization, Ministry of Education, College of Environmental Science and Engineering, North China Electric Power University, Beijing, 102206, China
| | - Haodong Ji
- The Key Laboratory of Water and Sediment Sciences, Ministry of Education, College of Environmental Sciences and Engineering, Peking University, Beijing, 100871, China
- The Beijing Innovation Center for Engineering Science and Advanced Technology (BIC-ESAT), Peking University, Beijing, 100871, China
- Beijing Engineering Research Center for Advanced Wastewater Treatment, Department of Environmental Engineering, Peking University, Beijing, 100871, China
| | - Jun Duan
- The Key Laboratory of Water and Sediment Sciences, Ministry of Education, College of Environmental Sciences and Engineering, Peking University, Beijing, 100871, China
| | - Chenyuan Dang
- The Key Laboratory of Water and Sediment Sciences, Ministry of Education, College of Environmental Sciences and Engineering, Peking University, Beijing, 100871, China
| | - Xingmin Chen
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China
| | - Wen Liu
- The Key Laboratory of Water and Sediment Sciences, Ministry of Education, College of Environmental Sciences and Engineering, Peking University, Beijing, 100871, China
- The Beijing Innovation Center for Engineering Science and Advanced Technology (BIC-ESAT), Peking University, Beijing, 100871, China
- Beijing Engineering Research Center for Advanced Wastewater Treatment, Department of Environmental Engineering, Peking University, Beijing, 100871, China
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16
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Zhao T, Fang M, Tang Z, Zhao X, Wu F, Giesy JP. Adsorption, aggregation and sedimentation of titanium dioxide nanoparticles and nanotubes in the presence of different sources of humic acids. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 692:660-668. [PMID: 31539974 DOI: 10.1016/j.scitotenv.2019.07.312] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 07/18/2019] [Accepted: 07/19/2019] [Indexed: 06/10/2023]
Abstract
Environmental behavior, bioavailability and risks posed by TiO2, nanomaterials (TiO2 NMs) in surface waters are affected by morphologies of the particles and geochemistry, including pH, inorganic and organic matter. Here, the adsorption, aggregation and sedimentation of TiO2 nanoparticles (TiO2 NPs) and nanotubes (TiO2 NTs) were investigated in the presence of Elliott Soil humic acid (HAE) and Suwannee River humic acids (HAS). The adsorption amount of HA on TiO2 NMs was inversely proportional to pH of solution. Maximum adsorption amount of HA on the surface of TiO2 NMs follows the order TiO2 NPs + HAE (236.05 mg/g) > TiO2 NTs + HAE (146.05 mg/g) > TiO2 NTs + HAS (70.66 mg/g) > TiO2 NPs + HAS (37.48 mg/g). Stability of TiO2 NPs and TiO2 NTs largely depended on their isoelectric point, morphology and solution pH in the absence of HA. Dispersion of TiO2 NMs was enhanced with solution pH deviated from the isoelectric point of nanomaterials due to electrostatic repulsion. Moreover, tubular structures of TiO2 NTs with higher length-diameter ratio seem to aggregate more easily than dose sphere-like TiO2 NPs. This might be due to their spherical structure enhancing steric repulsion. Notably, the adsorption of HA led to disagglomeration and significant stability of TiO2 NPs and TiO2 NTs due to steric hindrance under varying solution pH. In addition, adsorption time, concentration and sources of HA also influenced suspension/sedimentation behavior of TiO2 NPs and TiO2 NTs, and aromatic-rich HAE stabilized TiO2 NMs suspension more aggressively than aliphatic-rich HAS.
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Affiliation(s)
- Tianhui Zhao
- College of Water Sciences, Beijing Normal University, Beijing 100875, China; State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Mengyuan Fang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming, Yunnan 650550, China
| | - Zhi Tang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
| | - Xiaoli Zhao
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Fengchang Wu
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - John P Giesy
- Department of Veterinary Biomedical Sciences and Toxicology Centre, University of Saskatchewan, Saskatoon, Saskatchewan, Canada; Department of Environmental Science, Baylor University, Waco, TX, United States
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17
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Xu X, Liu Y, Wang T, Ji H, Chen L, Li S, Liu W. Co-adsorption of ciprofloxacin and Cu(II) onto titanate nanotubes: Speciation variation and metal-organic complexation. J Mol Liq 2019. [DOI: 10.1016/j.molliq.2019.111375] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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18
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Oh SH, Jeong S, Kim IS, Shon HK, Jang A. Removal behaviors and fouling mechanisms of charged antibiotics and nanoparticles on forward osmosis membrane. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 247:385-393. [PMID: 31254754 DOI: 10.1016/j.jenvman.2019.06.070] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 06/07/2019] [Accepted: 06/14/2019] [Indexed: 06/09/2023]
Abstract
Fouling and rejection mechanisms of both charged antibiotics (ABs) and nanoparticles (NPs) were determined using a negatively-charged polyamide thin film composite forward osmosis (FO) flat sheet membrane. Two types of ABs and NPs were selected as positively and negatively charged foulants at pH 8. The ABs did not cause significant membrane fouling, but the extent of fouling and rejection changed based on the electrostatic attraction or repulsion forces. The addition of opposite charged AB and NP resulted in a decline of the membrane flux by 11.0% but a 6.5% AB average rejection efficiency improvement. On the other hand, mixing of like-charged ABs and NPs generated repulsive forces that improved average rejection efficiency about 5.5% but made no changes in the membrane flux. In addition, NPs and ABs were mixed and tested at various concentrations and pH levels to rectify the behavior of ABs. The aggregate size and removal efficiency were observed to vary with the change in the electron double layer of the mixture. It can help to make the strategy to control the ABs in the FO process and consequently it enables the FO process to produce environmentally safe effluent.
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Affiliation(s)
- Sang-Hun Oh
- Graduate School of Water Resources, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon-si, Gyeonggi-do, 16419, Republic of Korea
| | - Sanghyun Jeong
- Graduate School of Water Resources, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon-si, Gyeonggi-do, 16419, Republic of Korea
| | - In S Kim
- School of Earth Sciences and Environmental Engineering, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, Republic of Korea; Global Desalination Research Center, Gwangju Institute of Science and Technology (GIST), 123 Cheomdanwagi-ro, Buk-gu, Gwangju, 61005, Republic of Korea
| | - Ho Kyong Shon
- School of Civil and Environmental Engineering, University of Technology Sydney (UTS), City Campus, Broadway, NSW, 2007, Australia
| | - Am Jang
- Graduate School of Water Resources, Sungkyunkwan University (SKKU), 2066 Seobu-ro, Jangan-gu, Suwon-si, Gyeonggi-do, 16419, Republic of Korea.
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19
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20
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Preparation, characterization of titanate nanosheet–pozzolan nanocomposite and its use as an adsorbent for removal of diclofenac from simulated hospital effluents. J Taiwan Inst Chem Eng 2019. [DOI: 10.1016/j.jtice.2019.05.001] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
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21
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Effects of Ca 2+ and fulvic acids on atrazine degradation by nano-TiO 2: Performances and mechanisms. Sci Rep 2019; 9:8880. [PMID: 31222038 PMCID: PMC6586927 DOI: 10.1038/s41598-019-45086-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Accepted: 05/13/2019] [Indexed: 11/08/2022] Open
Abstract
In this study, the adsorption and UV photocatalytic degradation of atrazine using nano-TiO2 particles were studied systematically, and the colloidal stability of nano-TiO2 particles in solution was also investigated to reveal the removal mechanism. Experiments which contained the first 6.0 hours darkness and 4.0 hours UV illumination later were conducted at different concentrations of Ca2+ and/or fulvic acids (FA) at pH = 7.0. Results showed that the adsorption rate of atrazine onto nano-TiO2 particles decreased with the increase of Ca2+ and/or FA concentrations, which could be explained well by the colloidal stability of nanoparticles. When the solution contained Ca2+ or Ca2+-FA, the nanoparticles were aggregated together leading to the decrease of the contact surface area. Besides, there existed competitive adsorption between FA and atrazine on the particle surface. During photocatalytic degradation, the increase of Ca2+ and/or FA concentration accelerated the aggregation of nano-TiO2 particles and that reduced the degradation efficiency of atrazine. The particle sizes by SEM were in accordance with the aggregation degree of nanoparticles in the solutions. Sedimentation experiments of nano-TiO2 particles displayed that the fastest sedimentation was happened in the CaCl2 and FA coexistent system and followed by CaCl2 alone, and the results well demonstrated the photodegradation efficiency trends of atrazine by nano-TiO2 particles under the different sedimentation conditions.
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22
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Wang X, Liu W, Fu H, Yi XH, Wang P, Zhao C, Wang CC, Zheng W. Simultaneous Cr(VI) reduction and Cr(III) removal of bifunctional MOF/Titanate nanotube composites. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 249:502-511. [PMID: 30928522 DOI: 10.1016/j.envpol.2019.03.096] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 03/13/2019] [Accepted: 03/23/2019] [Indexed: 06/09/2023]
Abstract
In this study, a series of BUC-21/titanate nanotube (BT-X) composites were facilely fabricated via ball-milling of 2-dimensional (2D) metal-organic framework (MOF) BUC-21 and titanate nanotubes (TNTs). The BT-X composites were characterized by powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), UV-visible diffuse-reflectance spectroscopy (UV-vis DRS), X-ray photoelectron spectrometer (XPS) and high resolution transmission electron microscopy (HRTEM). Both the photocatalytic reduction from Cr(VI) to Cr(III) and adsorptive removal of formed Cr(III) of BT-X composites were systematically investigated under different conditions including pH values and co-existing inorganic ions. It was found that BUC-21 (100 mg)/TNTs (100 mg) (BT-1) composites demonstrate remarkable ability of photocatalytic Cr(VI) reduction and adsorptive Cr(III) removal, as well as good reusability and stability. It is believed that the introduction of TNTs could capture the formed Cr(III) from the surface of BUC-21, which provided more active sites exposed to enhance the Cr(VI) reduction.
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Affiliation(s)
- Xun Wang
- Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation/Beijing Advanced Innovation Centre for Future Urban Design, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
| | - Wen Liu
- The Key Laboratory of Water and Sediment Sciences, Ministry of Education, College of Environment Sciences and Engineering, Peking University, Beijing 100871, China
| | - Huifen Fu
- Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation/Beijing Advanced Innovation Centre for Future Urban Design, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
| | - Xiao-Hong Yi
- Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation/Beijing Advanced Innovation Centre for Future Urban Design, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
| | - Peng Wang
- Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation/Beijing Advanced Innovation Centre for Future Urban Design, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
| | - Chen Zhao
- Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation/Beijing Advanced Innovation Centre for Future Urban Design, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
| | - Chong-Chen Wang
- Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation/Beijing Advanced Innovation Centre for Future Urban Design, Beijing University of Civil Engineering and Architecture, Beijing 100044, China.
| | - Weiwei Zheng
- Department of Chemistry, Syracuse University, Syracuse, NY 13244, United States
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23
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Improved performance of titanate nanostructures for manganese adsorption and posterior pollutants photocatalytic degradation. J Photochem Photobiol A Chem 2019. [DOI: 10.1016/j.jphotochem.2019.04.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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24
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Sáringer S, Rouster P, Szilágyi I. Regulation of the Stability of Titania Nanosheet Dispersions with Oppositely and Like-Charged Polyelectrolytes. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:4986-4994. [PMID: 30888825 DOI: 10.1021/acs.langmuir.9b00242] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Charging and aggregation processes of titania nanosheets (TNS) were extensively studied in the presence of oppositely charged or like-charged polyelectrolytes in aqueous dispersions. The surface charge of the TNS was systematically varied by the pH; therefore, positive nanosheets were obtained at pH 4 and negative ones at pH 10. Strong adsorption of poly(styrene sulfonate) (PSS) of high negative line charge density on the TNS was observed at pH 4, leading to charge neutralization and reversal of the original sign of charge of the nanosheets. The adsorption of like-charged poly(diallyldimethylammonium chloride) (PDADMAC) was also feasible through a hydrophobic interaction. The predominating interparticle forces were mainly of the DLVO-type, but additional patch-charge attraction also took place in the case of PSS at low surface coverage. The TNS was found to be hydrophilic at pH 10 and no adsorption of like-charged PSS was possible because of strong electrostatic repulsion between the polyelectrolyte and the surface. The PDADMAC showed high affinity to the oppositely charged TNS surface in alkaline dispersions, giving rise to neutral and positively charged nanosheets at appropriate polyelectrolyte doses. Formation of a saturated PDADMAC layer on the TNS led to high resistance against salt-induced aggregation through the electrosteric stabilization mechanism. These results shed light on the importance of polyelectrolyte concentration, ionic strength, and charge balance on the colloidal stability of TNS, which is especially important in applications, where the nanosheets are dispersed in complex solution containing polymeric compounds and electrolytes.
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Affiliation(s)
| | - Paul Rouster
- Institute of Condensed Matter and Nanosciences-Bio and Soft Matter , Université Catholique de Louvain , B-1348 Louvain-la-Neuve , Belgium
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25
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Gora SL, Andrews SA. Removal of natural organic matter and disinfection byproduct precursors from drinking water using photocatalytically regenerable nanoscale adsorbents. CHEMOSPHERE 2019; 218:52-63. [PMID: 30469004 DOI: 10.1016/j.chemosphere.2018.11.102] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 10/23/2018] [Accepted: 11/14/2018] [Indexed: 06/09/2023]
Abstract
Disinfection byproduct precursors (DBPs) were removed from raw surface water obtained from two Canadian drinking water treatment plants via adsorption to two regenerable linear engineered TiO2 nanomaterials (LENs). The temperature employed in the final heating step of the LEN synthesis procedure was varied to produce two distinct nanomaterials, NB 550 and NB 700. The LENs had similar dimensions but differed in terms of surface characteristics, surface area, and crystal structure. Unlike the commercial TiO2 nanoparticles, both LENs were easily removed from the treated water via settling or filtration. Although neither of the LENs were as effective for NOM adsorption as commercial nanoparticles, both were able to remove substantial amounts of DBP precursors. NB 550 reduced the trihalomethane (THM) formation potential of both water sources by up to 40% and their haloacetic acid (HAA) formation potential by approximately 50%. NB 700 reduced the THM formation potential of one water source by 25% and that of the other by 40%. HAA precursor removal by NB 700 ranged from 25% to 30%. The adsorption of DOC, UV254, THM precursors, and HAA precursors by commercial nanoparticles and the LENs fit a modified Freundlich adsorption isotherm model. When the LENs were regenerated via exposure to UVA light they experienced a gradual loss in adsorption capacity of up to 50% over five regeneration cycles. This loss occurred more quickly for the less photoactive of the two nanomaterials, and was affected by water source, suggesting that components of the water matrices may have interfered with regeneration.
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Affiliation(s)
- Stephanie L Gora
- Department of Civil Engineering, University of Toronto, 35 St. George Street, Toronto, Ontario, M5S 1A4, Canada.
| | - Susan A Andrews
- Department of Civil Engineering, University of Toronto, 35 St. George Street, Toronto, Ontario, M5S 1A4, Canada.
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26
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Effect of Ionic Compounds of Different Valences on the Stability of Titanium Oxide Colloids. COLLOIDS AND INTERFACES 2018. [DOI: 10.3390/colloids2030032] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Titanium oxide particles of various morphologies have been prepared for applications of scientific or industrial interest in recent decades. Besides development of novel synthetic routes and solid-state characterization of the obtained particles, colloidal stability of titanium oxide dispersions was the focus of numerous research groups due to the high importance of this topic in applications in heterogeneous systems. The influence of dissolved ionic compounds, including monovalent salts, multivalent ions and polyelectrolytes, on the charging and aggregation behaviour of titanium oxide materials of spherical and elongated structures will be discussed in the present review.
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27
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Liu G, Mei H, Tan X, Zhang H, Liu H, Fang M, Wang X. Enhancement of Rb+ and Cs+ removal in 3D carbon aerogel-supported Na2Ti3O7. J Mol Liq 2018. [DOI: 10.1016/j.molliq.2018.04.117] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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28
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Baranidharan S, Kumar A. Preliminary evidence of nanoparticle occurrence in water from different regions of Delhi (India). ENVIRONMENTAL MONITORING AND ASSESSMENT 2018; 190:240. [PMID: 29568994 DOI: 10.1007/s10661-018-6529-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Accepted: 02/07/2018] [Indexed: 06/08/2023]
Abstract
The objective of this study was to obtain preliminary evidence of metal-based nanoparticle (NP) occurrence in Delhi (India). Six sampling locations (inlets and outlets of two different municipal wastewater treatment plants (WWTPs), groundwater, and river water) were collected in three independent sampling events. Microscopic analysis (TEM) found majority (40%) of the particles ranged between 150 and 200 nm followed by particles of size 100-150 nm (22%) at the inlet of WWTP, while at outlet, 90% of the particles were < 100 nm. Compared with the outlet of the WWTPs, particles at the inlet were found to be greater than 40%. Intensity-based particle size distribution (PSD) revealed particle size at influent in the range of 210 nm, while at effluent, particle size for both WWTPs ranged < 100 nm. Particles of size between 100 and 200 nm were found to get removed from both the treatment plants and thus making it evident that NP gets settled or adsorbed in sludge. Spectral analysis (EDX) further confirmed the presence of metals such as Al, As, Ag, Mn, Fe, Ti, and Zn at different weight percentages. Overall, findings of this study confirmed the presence of metal-based engineered NPs (ENPs) from anthropogenic sources and it cannot also be ruled out the possible formation of NPs within the wastewater from natural minerals. Moreover, to solve definitive clues for ascertaining the sources of NPs in complex samples, more sophisticated research techniques, such as inductively coupled plasma-mass spectrometry (ICP-MS) in combination with field flow fractionation, single-particle ICP-MS, and radio-labeling in combination or in single should be considered.
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Affiliation(s)
- S Baranidharan
- Department of Civil Engineering, Indian Institute of Technology, Delhi, India
| | - Arun Kumar
- Department of Civil Engineering, Indian Institute of Technology, Delhi, India.
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29
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Lv B, Wang C, Hou J, Wang P, Miao L, You G, Yang Y, Xu Y, Zhang M, Ci H. Towards a better understanding on aggregation behavior of CeO 2 nanoparticles in different natural waters under flow disturbance. JOURNAL OF HAZARDOUS MATERIALS 2018; 343:235-244. [PMID: 28963887 DOI: 10.1016/j.jhazmat.2017.09.039] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Revised: 09/21/2017] [Accepted: 09/23/2017] [Indexed: 06/07/2023]
Abstract
The fate of nanoparticles in natural waters is affected by the combination of various factors, especially the flow disturbance which plays a decisive role in the transport of nanoparticles. This study investigated the aggregation behavior of CeO2 nanoparticles (NPs) in natural waters by using a unique instrument to simulate flow disturbance. The results indicated that, in the absence of a shear force, the CeO2 NPs formed linear, chain-like aggregates in seawater, owing to the high IS, which compressed the electrical double layer of particles. On the other hand, the NPs formed more compact aggregates in lake water, owing to an ion bridge effect between the NPs and the dissolved organic matter (DOM). It was also found that shear forces affected the aggregation behavior of the NPs. A low shear force promoted the aggregation of the NPs by increasing the collision efficiency while the aggregates were broken by a high shear force. Remarkably, the NPs maintained their potential for continuous aggregation when the slow stirring was reintroduced, suggesting that the aggregates began to grow again under renewed stirring. The results of this study could help in predicting the fate and transport behavior of CeO2 NPs in actual aquatic environments.
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Affiliation(s)
- Bowen Lv
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, People's Republic of China
| | - Chao Wang
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, People's Republic of China
| | - Jun Hou
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, People's Republic of China.
| | - Peifang Wang
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, People's Republic of China.
| | - Lingzhan Miao
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, People's Republic of China
| | - Guoxiang You
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, People's Republic of China
| | - Yangyang Yang
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, People's Republic of China
| | - Yi Xu
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, People's Republic of China
| | - Mingzhi Zhang
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, People's Republic of China
| | - Hanlin Ci
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, People's Republic of China
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Qi N, Wang P, Wang C, Ao Y. Effect of a typical antibiotic (tetracycline) on the aggregation of TiO 2 nanoparticles in an aquatic environment. JOURNAL OF HAZARDOUS MATERIALS 2018; 341:187-197. [PMID: 28780433 DOI: 10.1016/j.jhazmat.2017.07.046] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2016] [Revised: 07/13/2017] [Accepted: 07/20/2017] [Indexed: 05/22/2023]
Abstract
The effect of tetracycline (TC) on the behavior of TiO2 nanoparticles (NPs) in solution is investigated. The results illustrate that TC molecules do not exhibit an obvious effect on the aggregation of TiO2 NPs under circumneutral conditions (pH of approximately 5.5). However, the TC molecules exhibit a remarkable effect on the behavior of TiO2 NPs when the environmental factors (such as pH, ionic strength, and humic acid; HA) are adjusted. In the pH range from 3.0 to 10.0, the zeta potentials of NPs become more positively charged after TC adsorption. The point of zero charge of the TiO2 NPs increases from 6.5 to 7.5. The stability of the TiO2 NPs is improved after TC adsorption in different salt solutions. The critical coagulation concentration (CCC) increases from 10.57mmol/L to 17.21mmol/L, 4.95mmol/L to 9.73mmol/L, and 0.23-1.67mmol/L in the presence of NaCl, CaCl2, and Na2SO4 (where Cl- and SO42- are the counter-ions), respectively. Under different HA concentrations, the CHAPZC (the HA concentration that causes the zeta potential of NPs to be zero) increases from 0.5mg/L to 1.3mg/L after TC adsorption. The sizes of the TiO2 NP aggregates are larger than those without TC adsorption. All of these results are due to an increase in the surface charge of the TiO2 NPs after TC adsorption. The adsorption of H+ during TC adsorption causes protonation of the dimethylamine group on the TC molecules.
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Affiliation(s)
- Ning Qi
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China
| | - Peifang Wang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China.
| | - Chao Wang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China
| | - Yanhui Ao
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China.
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Zhao X, Du P, Cai Z, Wang T, Fu J, Liu W. Photocatalysis of bisphenol A by an easy-settling titania/titanate composite: Effects of water chemistry factors, degradation pathway and theoretical calculation. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 232:580-590. [PMID: 28988872 DOI: 10.1016/j.envpol.2017.09.094] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2017] [Revised: 09/24/2017] [Accepted: 09/28/2017] [Indexed: 06/07/2023]
Abstract
Bisphenol A (BPA) is a widely concerned endocrine disrupting chemical and hard to be removed through conventional wastewater treatment processes. In this study, we developed a TiO2 decorated titanate nanotubes composite (TiO2/TNTs) and used for photocatalytic degradation of BPA. TEM and XRD analysis show that the TiO2/TNTs is a nano-composite of anatase and titanate, with anatase acting as the primary photocatalytic site and titanate as the skeleton. TiO2/TNTs exhibited excellent photocatalytic reactivity and its easy-settling property leaded to good reusability. After 5 reuse cycles, TiO2/TNTs also could photo-degrade 91.2% of BPA with a high rate constant (k1) of 0.039 min-1, which was much better than TiO2 and TNTs. Higher pH facilitated photocatalysis due to more reactive oxygen species produced and less material aggregation. The presence of NaCl and CaCl2 showed negligible effects on BPA degradation, but NaHCO3 caused an inhibition effect resulting from consumption of ·OH. Humic acid inhibited degradation mainly due to blockage of the active sites of TiO2/TNTs. Degradation pathway was well interpreted through theoretical calculation. Hydroxyl radical played the dominate role in BPA photodegradation, and the atoms of BPA with high Fukui index based on density-functional theory (DFT) calculation are the radical easy-attacking (f0) sites. Considering the good photocatalytic reactivity, reusability, stability and settle property, TiO2/TNTs promises to be an efficient alternative for removal of organic compounds from wastewaters.
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Affiliation(s)
- Xiao Zhao
- College of Environmental Sciences and Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, 100871, China; Center for Agricultural Water Research in China, China Agricultural University, Beijing 100083, China
| | - Penghui Du
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, United States
| | - Zhengqing Cai
- Department of Environmental Science & Engineering, Fudan University, Shanghai, 200433, PR China
| | - Ting Wang
- College of Environmental Sciences and Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, 100871, China
| | - Jie Fu
- Department of Environmental Science & Engineering, Fudan University, Shanghai, 200433, PR China.
| | - Wen Liu
- College of Environmental Sciences and Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, 100871, China; School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, United States.
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Gora SL, Andrews SA. Adsorption of natural organic matter and disinfection byproduct precursors from surface water onto TiO 2 nanoparticles: pH effects, isotherm modelling and implications for using TiO 2 for drinking water treatment. CHEMOSPHERE 2017; 174:363-370. [PMID: 28187382 DOI: 10.1016/j.chemosphere.2017.01.125] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 01/22/2017] [Accepted: 01/24/2017] [Indexed: 06/06/2023]
Abstract
Titanium dioxide is a photocatalyst that can remove organic contaminants of interest to the drinking water treatment industry, including natural organic matter (NOM) and disinfection byproduct (DBP) precursors. The photocatalytic reaction occurs in two steps: adsorption of the contaminant followed by degradation of the adsorbed contaminant upon irradiation with UV light. The second part of this process can lead to the formation of reactive intermediates and negative impacts on treated water quality, such as increased DBP formation potential (DBPfp). Adsorption alone does not result in the formation of reactive intermediates and thus may prove to be a safe way to incorporate TiO2 into drinking water treatment processes. The goal of this study was to expand on the current understanding of NOM adsorption on TiO2 and examine it in a drinking water context by observing NOM adsorption from real water sources and evaluating the effects of the resulting reductions on the DBPfp of the treated water. Bottle point isotherm tests were conducted with raw water from two Canadian water treatment plants adjusted to pH 4, pH 6 and pH 8 and dosed with TiO2 nanoparticles. The DOC results were a good fit to a modified Freundlich isotherm. DBP precursors and liquid chromatography with organic carbon detection NOM fractions associated with DBP formation were removed to some extent at all pHs, but most effectively at pH 4.
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Affiliation(s)
- Stephanie L Gora
- Department of Civil Engineering, University of Toronto, 35 St. George Street, Toronto, Ontario M5S 1A4, Canada.
| | - Susan A Andrews
- Department of Civil Engineering, University of Toronto, 35 St. George Street, Toronto, Ontario M5S 1A4, Canada.
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He H, Cheng Y, Yang C, Zeng G, Zhu C, Yan Z. Influences of anion concentration and valence on dispersion and aggregation of titanium dioxide nanoparticles in aqueous solutions. J Environ Sci (China) 2017; 54:135-141. [PMID: 28391922 DOI: 10.1016/j.jes.2016.06.009] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Revised: 06/17/2016] [Accepted: 06/22/2016] [Indexed: 05/17/2023]
Abstract
Dispersion and aggregation of nanoparticles in aqueous solutions are important factors for safe application of nanoparticles. In this study, dispersion and aggregation of nano-TiO2 in aqueous solutions containing various anions were investigated. The influences of anion concentration and valence on the aggregation size, zeta potential and aggregation kinetics were individually investigated. Results showed that the zeta potential decreased from 19.8 to -41.4mV when PO43- concentration was increased from 0 to 50mg/L, while the corresponding average size of nano-TiO2 particles decreased from 613.2 to 540.3nm. Both SO42- and NO3- enhanced aggregation of nano-TiO2 in solution. As SO42- concentration was increased from 0 to 500mg/L, the zeta potential decreased from 19.8 to 1.4mV, and aggregate sizes increased from 613.2 to 961.3nm. The trend for NO3- fluctuation was similar to that for SO42- although the range of variation for NO3- was relatively narrow. SO42- and NO3- accelerated the aggregation rapidly, while PO43- did so slowly. These findings facilitate the understanding of aggregation and dispersion mechanisms of nano-TiO2 in aqueous solutions in the presence of anions of interest.
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Affiliation(s)
- Huijun He
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China.
| | - Yan Cheng
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Chunping Yang
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China; Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, College of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, Zhejiang 310018, China.
| | - Guangming Zeng
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Canyao Zhu
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Zhou Yan
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
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Hua S, Yu X, Li F, Duan J, Ji H, Liu W. Hydrogen titanate nanosheets with both adsorptive and photocatalytic properties used for organic dyes removal. Colloids Surf A Physicochem Eng Asp 2017. [DOI: 10.1016/j.colsurfa.2016.12.031] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Fan G, Lin R, Su Z, Lin X, Xu R, Chen W. Removal of Cr (VI) from aqueous solutions by titanate nanomaterials synthesized via hydrothermal method. CAN J CHEM ENG 2016. [DOI: 10.1002/cjce.22727] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Affiliation(s)
- Gongduan Fan
- College of Civil Engineering; Fuzhou University; Fuzhou, 350108 China
- Institute of Advanced Energy Materials; Fuzhou University; Fuzhou Fujian 350002 China
| | - Rujing Lin
- College of Civil Engineering; Fuzhou University; Fuzhou, 350108 China
| | - Zhaoyue Su
- College of Civil Engineering; Fuzhou University; Fuzhou, 350108 China
| | - Xiuyong Lin
- College of Civil Engineering; Fuzhou University; Fuzhou, 350108 China
| | - Renxing Xu
- College of Civil Engineering; Fuzhou University; Fuzhou, 350108 China
| | - Wei Chen
- College of Civil Engineering; Fuzhou University; Fuzhou, 350108 China
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Lorenzetti M, Gongadze E, Kulkarni M, Junkar I, Iglič A. Electrokinetic Properties of TiO2 Nanotubular Surfaces. NANOSCALE RESEARCH LETTERS 2016; 11:378. [PMID: 27562014 PMCID: PMC4999383 DOI: 10.1186/s11671-016-1594-3] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/26/2016] [Accepted: 08/16/2016] [Indexed: 06/06/2023]
Abstract
Surface charge is one of the most significant properties for the characterisation of a biomaterial, being a key parameter in the interaction of the body implant with the surrounding living tissues. The present study concerns the systematic assessment of the surface charge of electrochemically anodized TiO2 nanotubular surfaces, proposed as coating material for Ti body implants. Biologically relevant electrolytes (NaCl, PBS, cell medium) were chosen to simulate the physiological conditions. The measurements were accomplished as titration curves at low electrolytic concentration (10(-3) M) and as single points at fixed pH but at various electrolytic concentrations (up to 0.1 M). The results showed that all the surfaces were negatively charged at physiological pH. However, the zeta potential values were dependent on the electrolytic conditions (electrolyte ion concentration, multivalence of the electrolyte ions, etc.) and on the surface characteristics (nanotubes top diameter, average porosity, exposed surface area, wettability, affinity to specific ions, etc.). Accordingly, various explanations were proposed to support the different experimental data among the surfaces. Theoretical model of electric double layer which takes into account the asymmetric finite size of ions in electrolyte and orientational ordering of water dipoles was modified according to our specific system in order to interpret the experimental data. Experimental results were in agreement with the theoretical predictions. Overall, our results contribute to enrich the state-of-art on the characterisation of nanostructured implant surfaces at the bio-interface, especially in case of topographically porous and rough surfaces.
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Affiliation(s)
| | - Ekaterina Gongadze
- Faculty of Electrical Engineering, University of Ljubljana, 1000, Ljubljana, Slovenia
| | - Mukta Kulkarni
- Faculty of Electrical Engineering, University of Ljubljana, 1000, Ljubljana, Slovenia
| | - Ita Junkar
- Jožef Stefan Institute, Jamova cesta 39, 1000, Ljubljana, Slovenia
| | - Aleš Iglič
- Faculty of Electrical Engineering, University of Ljubljana, 1000, Ljubljana, Slovenia.
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Liu W, Sun W, Borthwick AGL, Wang T, Li F, Guan Y. Simultaneous removal of Cr(VI) and 4-chlorophenol through photocatalysis by a novel anatase/titanate nanosheet composite: Synergetic promotion effect and autosynchronous doping. JOURNAL OF HAZARDOUS MATERIALS 2016; 317:385-393. [PMID: 27318735 DOI: 10.1016/j.jhazmat.2016.06.002] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Revised: 06/01/2016] [Accepted: 06/02/2016] [Indexed: 06/06/2023]
Abstract
Clean-up of wastewaters with coexisting heavy metals and organic contaminants is a huge issue worldwide. In this study, a novel anatase/titanate nanosheet composite material (labeled as TNS) synthesized through a one-step hydrothermal reaction was demonstrated to achieve the goal of simultaneous removal of Cr(VI) and 4-cholophenol (4-CP) from water. TEM and XRD analyses indicated the TNS was a nano-composite of anatase and titanate, with anatase acting as the primary photocatalysis center and titanate as the main adsorption site. Enhanced photocatalytic removal of co-existent Cr(VI) and 4-CP was observed in binary systems, with apparent rate constants (k1) for photocatalytic reactions of Cr(VI) and 4-CP about 3.1 and 2.6 times of that for single systems. In addition, over 99% of Cr(VI) and 4-CP was removed within 120min through photocatalysis by TNS at pH 7 in the binary system. Mechanisms for enhanced photocatalytic efficiency in the binary system are identified as: (1) a synergetic effect on the photo-reduction of Cr(VI) and photo-oxidation of 4-CP due to efficient separation of electron-hole pairs, and (2) autosynchronous doping because of reduced Cr(III) adsorption onto TNS. Furthermore, TNS could be efficiently reused after a simple acid-base treatment.
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Affiliation(s)
- Wen Liu
- Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China; The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Department of Environmental Engineering, Peking University, Beijing 100871, China; Environmental Engineering Program, Department of Civil Engineering, Auburn University, Auburn, AL 36849, USA.
| | - Weiling Sun
- The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Department of Environmental Engineering, Peking University, Beijing 100871, China
| | - Alistair G L Borthwick
- School of Engineering, The University of Edinburgh, The King's Buildings, Edinburgh EH9 3JL, UK
| | - Ting Wang
- The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Department of Environmental Engineering, Peking University, Beijing 100871, China
| | - Fan Li
- Environmental Engineering Program, Department of Civil Engineering, Auburn University, Auburn, AL 36849, USA
| | - Yidong Guan
- Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing 210044, China; Environmental Engineering Program, Department of Civil Engineering, Auburn University, Auburn, AL 36849, USA.
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38
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Liu W, Zhao X, Cai Z, Han B, Zhao D. Aggregation and stabilization of multiwalled carbon nanotubes in aqueous suspensions: influences of carboxymethyl cellulose, starch and humic acid. RSC Adv 2016. [DOI: 10.1039/c6ra10500a] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Aggregation and stability of multiwalled carbon nanotubes in aqueous solutions were investigated with two polysaccharide stabilizers (carboxymethyl cellulose and a water soluble starch) and a natural organic matter (leonardite humic acid).
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Affiliation(s)
- Wen Liu
- Environmental Engineering Program
- Department of Civil Engineering
- Auburn University
- Auburn
- USA
| | - Xiao Zhao
- Environmental Engineering Program
- Department of Civil Engineering
- Auburn University
- Auburn
- USA
| | - Zhengqing Cai
- Environmental Engineering Program
- Department of Civil Engineering
- Auburn University
- Auburn
- USA
| | - Bing Han
- Environmental Engineering Program
- Department of Civil Engineering
- Auburn University
- Auburn
- USA
| | - Dongye Zhao
- Environmental Engineering Program
- Department of Civil Engineering
- Auburn University
- Auburn
- USA
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39
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Ilyas SU, Pendyala R, Marneni N. Stability and Agglomeration of Alumina Nanoparticles in Ethanol-Water Mixtures. ACTA ACUST UNITED AC 2016. [DOI: 10.1016/j.proeng.2016.06.616] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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40
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Oprsal J, Blaha L, Pouzar M, Knotek P, Vlcek M, Hrda K. Assessment of silver nanoparticle toxicity for common carp (Cyprinus carpio) fish embryos using a novel method controlling the agglomeration in the aquatic media. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:19124-19132. [PMID: 26233755 DOI: 10.1007/s11356-015-5120-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2015] [Accepted: 07/23/2015] [Indexed: 06/04/2023]
Abstract
Formation of agglomerates and their rapid sedimentation during aquatic ecotoxicity testing of nanoparticles is a major issue with a crucial influence on the risk assessment of nanomaterials. The present work is aimed at developing and testing a new approach based on the periodic replacement of liquid media during an ecotoxicological experiment which enabled the efficient monitoring of exposure conditions. A verified mathematical model predicted the frequencies of media exchanges which checked for formation of agglomerates from silver nanoparticles AgNP with 50 nm average size of the original colloid. In the model experiments, embryos of common carp Cyprinus carpio were exposed repeatedly for 6 h to AgNPs (5-50 μm Ag L(-1)) either under semistatic conditions (exchange of media after 6 h) or in variants with frequent media exchanges (varying from 20 to 300 min depending on the AgNP colloid concentration and the desired maximum agglomerate size of 200 or 400 nm). In contrast to other studies, where dissolved free metals are usually responsible for toxic effects, our 144-h experiments demonstrated the importance of AgNP agglomerates in the adverse effects of nanosilver. Direct adsorption of agglomerates on fish embryos locally increased Ag concentrations which resulted in pronounced toxicity particularly in variants with larger 400 nm agglomerates. The present study demonstrates the suitability of the novel methodology in controlling the conditions during aquatic nanomaterial toxicity testing. It further provided insights into the mechanisms underlying the effects of AgNP, which rank on a global scale among the most widely used nanomaterials.
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Affiliation(s)
- Jakub Oprsal
- Faculty of Chemical Technology, Institute of Environmental and Chemical Engineering, University of Pardubice, Studentská 537, CZ-53210, Pardubice, Czech Republic.
| | - Ludek Blaha
- Faculty of Science, Masaryk University, RECETOX, Kamenice 5, 62500, Brno, Czech Republic
| | - Miloslav Pouzar
- Faculty of Chemical Technology, Institute of Environmental and Chemical Engineering, University of Pardubice, Studentská 537, CZ-53210, Pardubice, Czech Republic
| | - Petr Knotek
- Faculty of Chemical Technology, Department of General and Inorganic Chemistry, University of Pardubice, CZ-53210, Pardubice, Czech Republic
| | - Milan Vlcek
- Institute of Macromolecular Chemistry, Academy of Sciences of the Czech Republic, Heyrovsky sq. 2, 120 06, Prague, Czech Republic
| | - Katerina Hrda
- Faculty of Chemical Technology, Institute of Environmental and Chemical Engineering, University of Pardubice, Studentská 537, CZ-53210, Pardubice, Czech Republic
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41
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Alston JR, Banks DJ, McNeill CX, Mitchell JB, Popov LD, Shcherbakov IN, Poler JC. Adsorption studies of divalent, dinuclear coordination complexes as molecular spacers on SWCNTs. Phys Chem Chem Phys 2015; 17:29566-73. [PMID: 26457656 DOI: 10.1039/c5cp05419b] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In order to enhance the electrical energy storage capabilities of nanostructured carbon materials, inter-particle spacer strategies are needed to maintain ion-accessible surface area between the nanoparticles. This paper presents a comparison between different classes of divalent, dinuclear coordination complexes which both show strong adsorption to SWCNTs and have molecular spacer properties that maintain electrochemical activity. We find that a novel, dinuclear zinc hydrazone complex binds as an ion-pair at very high loading while not inducing significant aggregation as compared to our previously studies of dinuclear ruthenium complexes. These conclusions are supported by conductivity and dispersion stability data. Moreover, since zinc is an earth abundant metal, these complexes can be used as components in sustainable energy storage materials. Binding kinetics and binding equilibrium data are presented. Modeling of the adsorption isotherm is best fit with the BET model. Kinetics data support an independent binding model. Preliminary capacitance and membrane resistance data are consistent with the complexes acting as molecular spacers between the SWCNTs in a condensed thin film.
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Affiliation(s)
- Jeffrey R Alston
- Department of Chemistry, University of North Carolina at Charlotte, Charlotte, NC, USA.
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Van Koetsem F, Verstraete S, Van der Meeren P, Du Laing G. Stability of engineered nanomaterials in complex aqueous matrices: Settling behaviour of CeO2 nanoparticles in natural surface waters. ENVIRONMENTAL RESEARCH 2015; 142:207-214. [PMID: 26164115 DOI: 10.1016/j.envres.2015.06.028] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2015] [Revised: 06/03/2015] [Accepted: 06/23/2015] [Indexed: 06/04/2023]
Abstract
The stability of engineered nanoparticles (ENPs) in complex aqueous matrices is a key determinant of their fate and potential toxicity towards the aquatic environment and human health. Metal oxide nanoparticles, such as CeO2 ENPs, are increasingly being incorporated into a wide range of industrial and commercial applications, which will undoubtedly result in their (unintentional) release into the environment. Hereby, the behaviour and fate of CeO2 ENPs could potentially serve as model for other nanoparticles that possess similar characteristics. The present study examined the stability and settling of CeO2 ENPs (7.3±1.4 nm) as well as Ce(3+) ions in 10 distinct natural surface waters during 7d, under stagnant and isothermal experimental conditions. Natural water samples were collected throughout Flanders (Belgium) and were thoroughly characterized. For the majority of the surface waters, a substantial depletion (>95%) of the initially added CeO2 ENPs was observed just below the liquid surface of the water samples after 7d. In all cases, the reduction was considerably higher for CeO2 ENPs than for Ce(3+) ions (<68%). A first-order kinetics model was able to describe the observed time-dependant removal of both CeO2 ENPs (R(2)≥0.998) and Ce(3+) ions (R(2)≥0.812) from the water column, at least in case notable sedimentation occurred over time. Solution-pH appeared to be a prime parameter governing nanoparticle colloidal stability. Moreover, the suspended solids (TSS) content also seemed to be an important factor affecting the settling rate and residual fraction of CeO2 ENPs as well as Ce(3+) ions in natural surface waters. Correlation results also suggest potential association and co-precipitation of CeO2 ENPs with aluminium- and iron-containing natural colloidal material. The CeO2 ENPs remained stable in dispersion in surface water characterized by a low pH, ionic strength (IS), and TSS content, indicating the eventual stability and settling behaviour of the nanoparticles was likely determined by a combination of physicochemical parameters. Finally, ionic release from the nanoparticle surface was also examined and appeared to be negligible in all of the tested natural waters.
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Affiliation(s)
- Frederik Van Koetsem
- Laboratory of Analytical Chemistry and Applied Ecochemistry, Department of Applied Analytical and Physical Chemistry, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, Ghent, Belgium.
| | - Simon Verstraete
- Laboratory of Analytical Chemistry and Applied Ecochemistry, Department of Applied Analytical and Physical Chemistry, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, Ghent, Belgium
| | - Paul Van der Meeren
- Particle and Interfacial Technology Group, Department of Applied Analytical and Physical Chemistry, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, Ghent, Belgium
| | - Gijs Du Laing
- Laboratory of Analytical Chemistry and Applied Ecochemistry, Department of Applied Analytical and Physical Chemistry, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, Ghent, Belgium.
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Yang YJ, Kelkar AV, Zhu X, Bai G, Ng HT, Corti DS, Franses EI. Effect of sodium dodecylsulfate monomers and micelles on the stability of aqueous dispersions of titanium dioxide pigment nanoparticles against agglomeration and sedimentation. J Colloid Interface Sci 2015; 450:434-445. [DOI: 10.1016/j.jcis.2015.02.051] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 02/20/2015] [Indexed: 10/23/2022]
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Wang Y, Liu W, Wang T, Ni J. Arsenate adsorption onto Fe-TNTs prepared by a novel water–ethanol hydrothermal method: Mechanism and synergistic effect. J Colloid Interface Sci 2015; 440:253-62. [DOI: 10.1016/j.jcis.2014.10.036] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2014] [Revised: 10/18/2014] [Accepted: 10/21/2014] [Indexed: 02/01/2023]
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Szabó T, Tóth V, Horváth E, Forró L, Szilagyi I. Tuning the aggregation of titanate nanowires in aqueous dispersions. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2015; 31:42-9. [PMID: 25525741 DOI: 10.1021/la504521e] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Electrophoretic and dynamic light scattering (DLS) measurements revealed that aggregation in aqueous dispersion of titanate nanowires (TiONWs) can be tuned by poly(diallyldimethylammonium) chloride (PDADMAC) polyelectrolyte. The nanowires possessed negative charge under alkaline conditions which was compensated by the oppositely charged PDADMAC adsorbed on the surface. Such adsorption led to charge neutralization and subsequent charge reversal at the appropriate polyelectrolyte doses. The dispersions were stable at low PDADMAC concentration where the TiONWs possessed negative charge. However, fast aggregation of the nanowires occurred close to the charge neutralization point where the overall charge of the particles was zero. Charge inversion at high polyelectrolyte doses gave rise to restabilization of the samples and slow aggregation of the TiONWs even at higher ionic strengths where the original bare TiONW dispersions were unstable. The colloid stability of the bare nanowires can be explained well qualitatively by the Derjaguin, Landau, Verwey, and Overbeek (DLVO) theory; however, polyelectrolyte adsorption led to additional patch-charge attractions and osmotic repulsion between the particles. On the basis of the knowledge generated by the present work, experimental conditions (e.g., salt level, polyelectrolyte, and particle concentrations) can be adjusted in order to design stable and processable aqueous dispersions of TiONWs for further applications.
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Affiliation(s)
- Tamás Szabó
- Department of Inorganic and Analytical Chemistry, University of Geneva , 1205 Geneva, Switzerland
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Erol O, Unal HI. Core/shell-structured, covalently bonded TiO2/poly(3,4-ethylenedioxythiophene) dispersions and their electrorheological response: the effect of anisotropy. RSC Adv 2015. [DOI: 10.1039/c5ra20284a] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Higher surface area, rod-to-rod interactions and conducting thin shell induced covalently-bonded core/shell nanorod-TiO2/PEDOT nanocomposite to show stronger ER activity and higher recovery after stress loading compared to particulate one.
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Affiliation(s)
- O. Erol
- Gazi University
- Chemistry Department
- Smart Materials Research Lab
- Ankara 06500
- Turkey
| | - H. I. Unal
- Gazi University
- Chemistry Department
- Smart Materials Research Lab
- Ankara 06500
- Turkey
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Ilyas SU, Pendyala R, Marneni N. Dispersion behaviour and agglomeration effects of zinc oxide nanoparticles in ethanol–water mixtures. ACTA ACUST UNITED AC 2014. [DOI: 10.1179/1432891714z.000000000953] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Affiliation(s)
- S. U. Ilyas
- Chemical Engineering DepartmentUniversiti Teknologi PETRONAS, Bandar Seri Iskandar, 31750 Tronoh, Perak Darul Ridzuan, Malaysia
| | - R. Pendyala
- Chemical Engineering DepartmentUniversiti Teknologi PETRONAS, Bandar Seri Iskandar, 31750 Tronoh, Perak Darul Ridzuan, Malaysia
| | - N. Marneni
- Fundamental and Applied Sciences DepartmentUniversiti Teknologi PETRONAS, Bandar Seri Iskandar, 31750 Tronoh, Perak Darul Ridzuan, Malaysia
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48
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Ilyas SU, Pendyala R, Marneni N. Preparation, Sedimentation, and Agglomeration of Nanofluids. Chem Eng Technol 2014. [DOI: 10.1002/ceat.201400268] [Citation(s) in RCA: 102] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Philippe A, Schaumann GE. Interactions of dissolved organic matter with natural and engineered inorganic colloids: a review. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:8946-62. [PMID: 25082801 DOI: 10.1021/es502342r] [Citation(s) in RCA: 376] [Impact Index Per Article: 37.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
This contribution critically reviews the state of knowledge on interactions of natural colloids and engineered nanoparticles with natural dissolved organic materials (DOM). These interactions determine the behavior and impact of colloids in natural system. Humic substances, polysaccharides, and proteins present in natural waters adsorb onto the surface of most colloids. We outline major adsorption mechanisms and structures of adsorption layers reported in the literature and discuss their generality on the basis of particle type, DOM type, and media composition. Advanced characterization methods of both DOM and colloids are needed to address insufficiently understood aspects as DOM fractionation upon adsorption, adsorption reversibility, and effect of capping agent. Precise knowledge on adsorption layer helps in predicting the colloidal stability of the sorbent. While humic substances tend to decrease aggregation and deposition through electrostatic and steric effects, bridging-flocculation can occur in the presence of multivalent cations. In the presence of DOM, aggregation may become reversible and aggregate structure dynamic. Nonetheless, the role of shear forces is still poorly understood. If traditional approaches based on the DLVO-theory can be useful in specific cases, quantitative aggregation models taking into account DOM dynamics, bridging, and disaggregation are needed for a comprehensive modeling of colloids stability in natural media.
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Affiliation(s)
- Allan Philippe
- Institute for Environmental Sciences, Group of Environmental and Soil Chemistry, University Koblenz-Landau , Fortstraße 7, D-76829, Landau, Germany
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50
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Liu W, Zhang P, Borthwick AG, Chen H, Ni J. Adsorption mechanisms of thallium(I) and thallium(III) by titanate nanotubes: Ion-exchange and co-precipitation. J Colloid Interface Sci 2014; 423:67-75. [DOI: 10.1016/j.jcis.2014.02.030] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2013] [Accepted: 02/17/2014] [Indexed: 11/25/2022]
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