1
|
Acharya A, Jeppu G, Girish CR, Prabhu B, Murty VR, Martis AS, Ramesh S. Adsorption of arsenic and fluoride: Modeling of single and competitive adsorption systems. Heliyon 2024; 10:e31967. [PMID: 38868002 PMCID: PMC11167366 DOI: 10.1016/j.heliyon.2024.e31967] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2024] [Revised: 05/24/2024] [Accepted: 05/24/2024] [Indexed: 06/14/2024] Open
Abstract
The elevated co-occurrence of arsenic and fluoride in surface and groundwater poses risks to human health in many parts of the world. Using single and competitive batch equilibrium adsorption studies, this research focuses on As(V) and F adsorption by activated carbon and its modeling. BET, XRD, FESEM, EDS, and FTIR analysis were used to discern the structural characteristics of activated carbon. The influence of dosage, pH, and contact time were also investigated in single and simultaneous adsorption systems. The maximum adsorption capacity of activated carbon for arsenic and fluoride were found to be 3.58 mg/g and 2.32 mg/g, respectively. Kinetics studies indicated that pseudo-second-order kinetic model fit better than pseudo-first-order, Elovich, and intraparticle diffusion kinetic models. The non-linear regression analysis of Langmuir, Freundlich, Toth, Redlich Petersons, and Modified Langmuir Freundlich models was used to determine single-component asorption model parameters. Additionally, the simultaneous adsorption was rigorously modeled and compared using the Extended Langmuir (EL), Extended Langmuir Freundlich (ELF), Modified Competitive Langmuir (MCL), and Jeppu Amrutha Manipal Multicomponent (JAMM) isotherm models, and competitive mechanisms were interpreted for the simultaneous adsorption system. Further, the model performances were evaluated by statistical error analysis using the normalized average percentage error (NAPE), root mean square errors (RMSE), and the correlation coefficient (R2). According to the modeling results, single equilibrium data fitted better with the Modified Langmuir Freundlich isotherm model, with a higher R2 of 0.99 and lower NAPE values of 3.8 % and 1.28 % for As(V) and F, than other models. For the binary adsorption, the Extended Langmuir Freundlich isotherm model demonstrated excellent fit with lowest errors. All the competitive isotherm models fit the As(V) and F simultaneous sorption systems reasonably well. Furthermore, the research unveiled a nuanced hierarchy of isotherm fitting, with ELF > EL > MCL > JAMM in varying arsenic at a constant fluoride concentration, and ELF > JAMM > EL > MCL in varying fluoride at a constant arsenic concentrations. In addition, competitive studies divulged crucial insights into selective adsorption, as As(V) exhibits a pronounced adsorption selectivity over F on activated carbon. In essence, As(V) showed a more pronounced antagonistic behavior over F, whereas F exhibited a much lesser competitive behavior in the adsorption of arsenic.
Collapse
Affiliation(s)
- Amrutha Acharya
- Department of Chemical Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, 576104, Karnataka, India
| | - Gautham Jeppu
- Department of Chemical Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, 576104, Karnataka, India
| | - Chikmagalur Raju Girish
- Department of Chemical Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, 576104, Karnataka, India
| | - Balakrishna Prabhu
- Department of Chemical Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, 576104, Karnataka, India
| | - Vytla Ramachandra Murty
- Department of Biotechnology, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, 576104, Karnataka, India
| | - Alita Stephy Martis
- Department of Chemical Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, 576104, Karnataka, India
| | - Shrividya Ramesh
- Department of Chemical Engineering, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, 576104, Karnataka, India
| |
Collapse
|
2
|
Medykowska M, Wiśniewska M, Szewczuk-Karpisz K, Galaburda M. Adsorption Capacity of Carbon-Silica Composites Towards Diclofenac in Poly(acrylic acid) Containing Systems: A Crucial Study on Common Wastewater Contaminants. Chemphyschem 2024; 25:e202300813. [PMID: 38430067 DOI: 10.1002/cphc.202300813] [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: 10/31/2023] [Revised: 02/21/2024] [Accepted: 02/28/2024] [Indexed: 03/03/2024]
Abstract
Diclofenac is one of the most popular over-the-counter non-steroidal anti-inflammatory drug and poly(acrylic acid) is a frequently used as thickener, filler or stabilizer. For these reasons, they are common organic contaminants in raw wastewater. The purpose of the presented studies was to compare the adsorption capacity of three carbon-silica composites - metal-free C/SiO2, iron-enriched C/Fe/SiO2 and manganese-enriched C/Mn/SiO2 towards diclofenac. The studies were carried out in single, and mixed systems in the presence of poly(acrylic acid) polymer. Adsorption, desorption and kinetics of the adsorption process were investigated. The concentration of diclofenac in the supernatants was determined using high-performance liquid chromatography. The solids were also characterized with an ASAP apparatus using low-temperature nitrogen desorption adsorption isotherms at liquid nitrogen temperature. In addition, potentiometric titrations and electrophoretic mobility measurements, as well as stability tests of the studied suspensions were carried out. The most efficient composite among investigated ones proved to be C/Fe/SiO2 removing diclofenac at the level of 46.68 mg/g for its initial concentration of 90 ppm. The results obtained clearly demonstrated that the carbon-silica composites are effective in separation of drugs from aqueous solutions and can be successfully used in the future for the removal of organic pollutants from water environment.
Collapse
Affiliation(s)
- Magdalena Medykowska
- Department of Radiochemistry and Environmental Chemistry, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Sklodowska University in Lublin, Maria Curie-Sklodowska Sq. 3, 20-031, Lublin, Poland
| | - Małgorzata Wiśniewska
- Department of Radiochemistry and Environmental Chemistry, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Sklodowska University in Lublin, Maria Curie-Sklodowska Sq. 3, 20-031, Lublin, Poland
| | | | - Mariia Galaburda
- Chuiko Institute of Surface Chemistry, National Academy of Sciences of Ukraine, General Naumov Street 17, 03164, Kyiv, Ukraine
- Department of Physicochemistry of Solid Surface, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie- Sklodowska University in Lublin, Maria Curie-Sklodowska Sq. 3, 20-031, Lublin, Poland
| |
Collapse
|
3
|
Wiśniewska M, Urban T, Tokarska K, Marciniak P, Giel A, Nowicki P. Removal of Organic Dyes, Polymers and Surfactants Using Carbonaceous Materials Derived from Walnut Shells. MATERIALS (BASEL, SWITZERLAND) 2024; 17:1987. [PMID: 38730794 PMCID: PMC11084864 DOI: 10.3390/ma17091987] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2024] [Revised: 04/19/2024] [Accepted: 04/23/2024] [Indexed: 05/13/2024]
Abstract
A series of new granular carbonaceous adsorbents was prepared via single-stage physical and chemical activation of walnut shells. Their suitability for removing various types of organic pollutants (represented by dyes, surfactants and water-soluble polymers) from the liquid phase was assessed. The activation of the precursor was carried out with CO2 and H3PO4 using conventional heating. Activated biocarbons were characterized in terms of chemical composition, acidic-basic nature of the surface, textural and electrokinetic properties as well as thermal stability. Depending on the type of activating agent used during the activation procedure, the obtained biocarbons differed in terms of specific surface area (from 401 to 1361 m2/g) and the type of porous structure produced (microporosity contribution in the range of 45-75%). Adsorption tests proved that the effectiveness of removing organic pollutants from the liquid phase depended to a large extent on the type of prepared adsorbent as well as the chemical nature and the molecular size of the adsorbate used. The chemically activated sample showed greater removal efficiency in relation to all tested pollutants. Its maximum adsorption capacity for methylene blue, poly(acrylic acid), poly(ethylene glycol) and Triton X-100 reached the levels of 247.1, 680.9, 38.5 and 61.8 mg/g, respectively.
Collapse
Affiliation(s)
- Małgorzata Wiśniewska
- Department of Radiochemistry and Environmental Chemistry, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Sklodowska University in Lublin, M. Curie-Sklodowska Sq. 3, 20-031 Lublin, Poland; (T.U.); (K.T.)
| | - Teresa Urban
- Department of Radiochemistry and Environmental Chemistry, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Sklodowska University in Lublin, M. Curie-Sklodowska Sq. 3, 20-031 Lublin, Poland; (T.U.); (K.T.)
| | - Karina Tokarska
- Department of Radiochemistry and Environmental Chemistry, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Sklodowska University in Lublin, M. Curie-Sklodowska Sq. 3, 20-031 Lublin, Poland; (T.U.); (K.T.)
| | - Paulina Marciniak
- Department of Applied Chemistry, Faculty of Chemistry, Adam Mickiewicz University in Poznań, Uniwersytetu Poznańskiego 8, 61-614 Poznań, Poland; (P.M.); (A.G.)
| | - Anna Giel
- Department of Applied Chemistry, Faculty of Chemistry, Adam Mickiewicz University in Poznań, Uniwersytetu Poznańskiego 8, 61-614 Poznań, Poland; (P.M.); (A.G.)
| | - Piotr Nowicki
- Department of Applied Chemistry, Faculty of Chemistry, Adam Mickiewicz University in Poznań, Uniwersytetu Poznańskiego 8, 61-614 Poznań, Poland; (P.M.); (A.G.)
| |
Collapse
|
4
|
Rossatto DL, de Lima R, Netto MS, Vieillard J, Silva LFO, Pinto D, Dotto GL. Transforming a volcanic rock powder waste into an efficient adsorbent to remove dyes (acid green 16 and acid red 97) and metals (Ag +, Co 2+, and Cu 2+) from water. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:124041-124052. [PMID: 37995034 DOI: 10.1007/s11356-023-31074-7] [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: 03/22/2023] [Accepted: 11/13/2023] [Indexed: 11/24/2023]
Abstract
This study searched for the best synthesis route for producing an adsorbent from the alkaline fusion of volcanic rock powder waste. The samples synthesized under different conditions of temperature and alkalizing ratio/precursor material, nine in total (NP.F, NP.F1, NP.F2, ...NP.F8 ), were used in the adsorption of acid green 16 (AG 16) and acid red 97 (AR 97) dyes and Ag+, Co2+, and Cu2+ ions. Subsequently, the 22 central composite rotational design (CCRD) was applied, and the effects of the alkalizing ratio (NaOH)/volcanic rock (VR) and temperature (T) on the synthesis process were analyzed in terms of their influence on the physical properties of the materials and in the process of adsorption of contaminants. From the experimental design, it can be seen that the independent variables alkalizing ratio/volcanic rock and temperature greatly influence the characteristic and synthesis of adsorbent materials by alkaline fusion, which in turn reflects on the results achieved in the adsorption of contaminants. Therefore, the temperature of 550 °C and NaOH/VR ratio equal to 1 was the most satisfactory synthesis route to obtain high values of adsorption capacity (q, mg g-1) and removal (R, %) for all studied contaminants, as well as the optimization of the physical characteristics of the material. For example, the adsorption capacity of dye AG 16 was 49.1 mg g-1, and for Ag+ was 66.2 mg g-1, while the removal percentages were 97.6% and 93.4%, respectively. This approach made it possible to transform volcanic rock powder wastes into an efficient adsorbent to treat contaminated waters with dyes and metals.
Collapse
Affiliation(s)
- Diovani L Rossatto
- Research Group on Adsorptive and Catalytic Process Engineering (ENGEPAC), Federal University of Santa Maria, Av. Roraima, 1000-7, 97105-900, Santa Maria, RS, Brazil
| | - Rachel de Lima
- Research Group on Adsorptive and Catalytic Process Engineering (ENGEPAC), Federal University of Santa Maria, Av. Roraima, 1000-7, 97105-900, Santa Maria, RS, Brazil
| | - Matias S Netto
- Research Group on Adsorptive and Catalytic Process Engineering (ENGEPAC), Federal University of Santa Maria, Av. Roraima, 1000-7, 97105-900, Santa Maria, RS, Brazil
| | - Julien Vieillard
- Normandie Université, UNIROUEN, INSA Rouen, CNRS, COBRA (UMR 6014), 27000, Evreux, France
| | - Luis F O Silva
- Department of Civil and Environmental, Universidad de La Costa, CUC, Calle 58 # 55-66, Atlántico, Barranquilla, Colombia
| | - Diana Pinto
- Department of Civil and Environmental, Universidad de La Costa, CUC, Calle 58 # 55-66, Atlántico, Barranquilla, Colombia
| | - Guilherme L Dotto
- Research Group on Adsorptive and Catalytic Process Engineering (ENGEPAC), Federal University of Santa Maria, Av. Roraima, 1000-7, 97105-900, Santa Maria, RS, Brazil.
- Normandie Université, UNIROUEN, INSA Rouen, CNRS, COBRA (UMR 6014), 27000, Evreux, France.
| |
Collapse
|
5
|
Medykowska M, Wiśniewska M, Galaburda M, Szewczuk-Karpisz K. Novel carbon-based composites enriched with Fe and Mn as effective and eco-friendly adsorbents of heavy metals in multicomponent solutions. CHEMOSPHERE 2023; 340:139958. [PMID: 37634587 DOI: 10.1016/j.chemosphere.2023.139958] [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: 06/13/2023] [Revised: 08/08/2023] [Accepted: 08/23/2023] [Indexed: 08/29/2023]
Abstract
With increasing demand for adsorbents highly effective in pollutant removal, carbon-based porous materials are becoming more and more popular. In this work, a new approach to the synthesis of such solids using an environmentally friendly, two-step preparation method is presented. A series of hybrid porous silica-containing carbon composites was synthesized, namely: metal free (C/SiO2), enriched with manganese (C/Mn/SiO2), as well as iron (C/Fe/SiO2). The effect of additives on the structure and morphology of the composites was evaluated using X-ray photoelectron spectroscopy (XPS), nitrogen adsorption/desorption and scanning electron microscope (SEM). The as-synthesized carbons were used as effective adsorbents for the simultaneous removal of heavy metals, including lead (Pb(II)) and zinc (Zn(II)) ions. In particular, it was determined that C/Mn/SiO2 sample demonstrated the highest adsorption capacity towards Pb(II) and Zn(II) ions. It was equal to 211.60 mg/g for Pb(II) and 74.95 mg/g for Zn(II). Zeta potential and surface charge density of the solids, with and without metals, were investigated to determine electrical double layer structure, whereas stability studies and aggregate size measurements were performed to estimate solid aggregation under selected conditions. It was established that solids with adsorbed metals formed suspensions with lower stability than those without ions. This, in turn, facilitates their separation from aqueous solutions.
Collapse
Affiliation(s)
- Magdalena Medykowska
- Department of Radiochemistry and Environmental Chemistry, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie- Sklodowska University in Lublin, Maria Curie-Sklodowska Sq. 3, 20-031, Lublin, Poland
| | - Małgorzata Wiśniewska
- Department of Radiochemistry and Environmental Chemistry, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie- Sklodowska University in Lublin, Maria Curie-Sklodowska Sq. 3, 20-031, Lublin, Poland
| | - Mariia Galaburda
- Chuiko Institute of Surface Chemistry, National Academy of Sciences of Ukraine, General Naumov Street 17, 03164, Kyiv, Ukraine
| | | |
Collapse
|
6
|
Yu S, Lu S, Zheng G. Reusable flexible poly(vinyl alcohol)/chitosan-based polymer carbon dots composite film for acid blue 93 dye adsorption. LUMINESCENCE 2023; 38:1552-1561. [PMID: 37328411 DOI: 10.1002/bio.4543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 04/13/2023] [Accepted: 04/17/2023] [Indexed: 06/18/2023]
Abstract
The design and synthesis of water-insoluble chitosan-based polymer carbon dots [P(CS-g-CA)CDs] are described. A polyvinyl alcohol/chitosan-based polymer carbon dot [PVA/P(CS-g-CA)CDs] composite film was prepared using a simple casting method to be used in dye adsorption. The composite film was characterized using FT-IR, XPS, transparency, contact angle, and mechanical properties tests, which showed the successful incorporation of P(CS-g-CA)CDs into the film and also revealed that hydrogen bonding improved the mechanical properties of the PVA film. Furthermore, the composite film displayed substantially enhanced hydrophobicity, making it suitable for use in aqueous environments. In addition, the composite film exhibited stable adsorption of acid blue 93 (AB93) at pH 2-9, with an enhanced adsorption capacity of 433.24 mg/g. The adsorption obeyed Langmuir law with an efficiency of more than 89% even after five cycles. Therefore, the PVA/P(CS-g-CA)CDs film is a promising material for the treatment of organic dye-polluted wastewater.
Collapse
Affiliation(s)
- Shujuan Yu
- Department of Materials Science and Engineering, Suqian University, Suqian, China
- Guangxi Key Laboratory of Natural Polymer Chemistry and Physics, College of Chemistry and Materials, Nanning Normal University, Nanning, China
| | - Shiyan Lu
- Guangxi Key Laboratory of Natural Polymer Chemistry and Physics, College of Chemistry and Materials, Nanning Normal University, Nanning, China
| | - Guangjian Zheng
- Guangxi Key Laboratory of Natural Polymer Chemistry and Physics, College of Chemistry and Materials, Nanning Normal University, Nanning, China
| |
Collapse
|
7
|
Szewczuk-Karpisz K, Kukowska S, Grygorczuk-Płaneta K, Kondracki B, Jerin K, Kovačević D. Scavenging of copper(II) ions, phosphate(V) ions, and diuron from aqueous media by goethite modified with chitosan or poly(acrylic acid). ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:79980-80000. [PMID: 37291344 PMCID: PMC10344844 DOI: 10.1007/s11356-023-27783-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2023] [Accepted: 05/16/2023] [Indexed: 06/10/2023]
Abstract
Goethite was modified by chitosan (CS) or poly(acrylic acid) (PAA) to improve its adsorptive abilities toward components of agrochemicals, i.e., copper ions (Cu), phosphate ions (P), and diuron. The pristine goethite effectively bound Cu (7.68 mg/g, 63.71%) and P (6.31 mg/g, 50.46%) only in their mixed systems. In the one adsorbate solutions, the adsorption levels accounted for 3.82 mg/g (30.57%) for Cu, 3.22 mg/g (25.74%) for P, and 0.15 mg/g (12.15%) for diuron. Goethite modification with CS or PAA did not yield spectacular results in adsorption. The maximum increase in adsorbed amount was noted for Cu ions (8.28%) after PAA modification as well as for P (6.02%) and diuron (24.04%) after CS modification. Both goethite modifications contributed to clear reduction in desorption of pollutants (even by 20.26% for Cu after PAA coating), which was mainly dictated by electrostatic attractive forces and hydrogen bonds formation occurring between macromolecules and impurities. The only exception in this phenomenon was Cu desorption from CS-modified solid-the polymer made it higher (to 95.00%). The Cu adsorption on PAA-modified goethite enhanced solid aggregation and thus facilitated metal cation separation from aqueous media. Consequently, the goethite modification with PAA was considered more promising for environmental remediation.
Collapse
Affiliation(s)
| | - Sylwia Kukowska
- Institute of Agrophysics, Polish Academy of Sciences, Doświadczalna 4, 20-290, Lublin, Poland
| | | | - Bartosz Kondracki
- Chair and Department of Cardiology, Medical University in Lublin, Jaczewskiego 8 (SPSK Nr 4), 20-954, Lublin, Poland
| | - Katarina Jerin
- Division of Physical Chemistry, Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, 10000, Zagreb, Croatia
| | - Davor Kovačević
- Division of Physical Chemistry, Department of Chemistry, Faculty of Science, University of Zagreb, Horvatovac 102a, 10000, Zagreb, Croatia
| |
Collapse
|
8
|
Removal of Cu (II) Via chitosan-conjugated iodate porous adsorbent: Kinetics, thermodynamics, and exploration of real wastewater sample. RESULTS IN CHEMISTRY 2023. [DOI: 10.1016/j.rechem.2023.100851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023] Open
|
9
|
Simultaneous Removal of Polymers with Different Ionic Character from Their Mixed Solutions Using Herb-Based Biochars and Activated Carbons. Molecules 2022; 27:molecules27217557. [DOI: 10.3390/molecules27217557] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2022] [Revised: 10/28/2022] [Accepted: 10/31/2022] [Indexed: 11/06/2022] Open
Abstract
Nettle and the sage herbs were used to obtain carbonaceous adsorbents. For the biochar preparation the precursors were dried and subjected to conventional pyrolysis. Activated carbons were obtained during precursor impregnation with phosphoric(V) acid and multistep pyrolysis. The textural parameters and acidic-basic properties of the obtained adsorbents were studied. The activated carbons prepared from the above herbs were characterized by the largely developed specific surface area. The obtained carbonaceous adsorbents were used for polymer removal from aqueous solution. Poly(acrylic acid) (PAA) and polyethylenimine (PEI) were chosen, due to their frequent presence in wastewater resulting from their extensive usage in many industrial fields. The influence of polymers on the electrokinetic properties of activated carbon were considered. PAA adsorption caused a decrease in the zeta potential and the surface charge density, whereas PEI increased these values. The activated carbons and biochars were used as polymer adsorbents from their single and binary solutions. Both polymers showed the greatest adsorption at pH 3. Poly (acrylic acid) had no significant effect on the polyethylenimine adsorbed amount, whereas PEI presence decreased the amount of PAA adsorption. Both polymers could be successfully desorbed from the activated carbons and biochar surfaces. The presented studies are innovatory and greatly required for the development of new environment protection procedures.
Collapse
|
10
|
Tomczyk A, Szewczuk-Karpisz K. Effect of Biochar Modification by Vitamin C, Hydrogen Peroxide or Silver Nanoparticles on Its Physicochemistry and Tetracycline Removal. MATERIALS 2022; 15:ma15155379. [PMID: 35955313 PMCID: PMC9369859 DOI: 10.3390/ma15155379] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 07/30/2022] [Accepted: 08/02/2022] [Indexed: 12/10/2022]
Abstract
Chemical modification of biochars can improve their adsorption capacity relative to antibiotics, posing a serious threat to the environment. Therefore, this research is aimed at the treatment of sunflower husk biochar (BC) by vitamin C, hydrogen peroxide or silver nanoparticles and the impact of this procedure on the biochar porosity, surface chemistry, and ability to remove tetracycline (TC). During the study, BC was produced by pyrolysis of sunflower husks at 650 °C. All solids were characterized using potentiometric titration, nitrogen adsorption/desorption, Fourier transform infrared spectroscopy, etc. The experimental adsorption data was described by kinetics equations: pseudo-first order, pseudo-second order, and particle internal diffusion (IPD) models as well as by isotherms of Langmuir, Langmuir-Freundlich, and Redlich-Peterson. The obtained results indicated that the biochar upgraded by vitamin C (BCV) had the highest ability to attract antibiotic molecules and, as a result, the TC adsorption on its surface was the largest. Furthermore, the TC desorption from this material was minimal. The measured TC adsorbed amounts for the modified BCs were as follows: 47.75% (7.47 mg/g) for BCV, 37.35% (8.41 mg/g)-for biochar treated by hydrogen peroxide (BCH), and 42.04% (9.55 mg/g) for biochar modified by silver nanoparticles (BCA). The lowest adsorption level was noted for non-modified biochar, i.e., 34.17% (6.83 mg/g). Based on the presented results it can be stated that the upgraded biochars had a good potential to improve the tetracycline removal from aqueous media, e.g., groundwater.
Collapse
|
11
|
Zubair M, Aziz HA, Ihsanullah I, Ahmad MA, Al-Harthi MA. Enhanced removal of Eriochrome Black T from water using biochar/layered double hydroxide/chitosan hybrid composite: Performance evaluation and optimization using BBD-RSM approach. ENVIRONMENTAL RESEARCH 2022; 209:112861. [PMID: 35143802 DOI: 10.1016/j.envres.2022.112861] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Revised: 01/25/2022] [Accepted: 01/27/2022] [Indexed: 06/14/2023]
Abstract
In this research work, a novel hybrid composite consisting of biochar (B), layered double hydroxide (CuFe) and chitosan (CS) (B-CuFe-CS) was produced using an ultrasonication-assisted co-precipitation method. The resultant composite was employed for adsorptive removal of Eriochrome black T (EBT) from water. Physicochemical characterization indicated that the B-CuFe-CS containing 10 wt % CS exhibited a heterogeneous structure with better crystallographic and textural characteristics. The B-CuFe-CS with abundant surface functionalities (-CO, -C-O, -OH, -NO3, and MMO), facilitates faster and enhanced removal of the EBT. The kinetic results showed better fitting to the pseudo-second order model, and equilibrium was achieved within 30 min. Equilibrium data was well explained by Langmuir and Redlich Peterson isotherm models (R2 > 0.98), indicating the EBT removal onto B-CuFe-CS followed monolayer adsorption. The maximum adsorption capacity was 806.4 mg/g, which was higher than pristine B-CuFe (476.19 mg/g) and many other adsorbents. The spectroscopic analysis (FTIR and XPS) and experimental results suggested that EBT adsorption is mainly governed by electrostatic, chemical and anion-exchange interactions. It is evident from these results that coupling B-CuFe composite with bio-filler (chitosan) resulted in an efficient bio-adsorbent to effectively purify dye-contaminated water streams.
Collapse
Affiliation(s)
- Mukarram Zubair
- Department of Environmental Engineering, Imam Abdulrahman bin Faisal University, Dammam, 31982, Saudi Arabia.
| | - Hamidi Abdul Aziz
- School of Civil Engineering, Engineering Campus, Universiti Sains Malaysia, 14300, Nibong Tebal, Pulau Pinang, Malaysia; Solid Waste Management Cluster, Engineering Campus, Universiti Sains Malaysia, 14300, Nibong Tebal, Pulau Pinang, Malaysia.
| | - Ihsanullah Ihsanullah
- Center for Environment & Water, Research Institute, King Fahd University of Petroleum and Minerals, Dhahran, 31261, Saudi Arabia.
| | - Mohd Azmier Ahmad
- School of Chemical Engineering, Engineering Campus, Universiti Sains Malaysia, 14300, Nibong Tebal, Pulau Pinang, Malaysia
| | - Mamdouh A Al-Harthi
- Department of Chemical Engineering, King Fahd University of Petroleum & Minerals, 31261, Dhahran, Saudi Arabia; Center of Research Excellences in Nanotechnology, King Fahd University of Petroleum & Minerals, 31261, Dhahran, Saudi Arabia
| |
Collapse
|
12
|
Ge J, Lian L, Wang X, Cao X, Gao W, Lou D. Coating layered double hydroxides with carbon dots for highly efficient removal of multiple dyes. JOURNAL OF HAZARDOUS MATERIALS 2022; 424:127613. [PMID: 34750003 DOI: 10.1016/j.jhazmat.2021.127613] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 10/15/2021] [Accepted: 10/24/2021] [Indexed: 06/13/2023]
Abstract
Layered double hydroxides (LDHs) and layered double oxides (LDOs) are desirable adsorption materials for printing and wastewater treatment owing to their outstanding anion exchange abilities, abundant active sites, and eco-friendly nature. In this study, a versatile LDO hybrid coated with carbon dots (CDs@MgAl-LDO) was constructed by modifying sodium dodecylbenzene sulfonate on the surface of MgAl-LDH as a carbon precursor, followed by ligand carbonization and hydrotalcite dehydration at 450 °C under N2 flow. CDs@MgAl-LDO displayed a hexagonal lamellar architecture with a plate lateral size of approximately 500 nm. It had a higher BET specific surface area (28.61 m2/g) than MgAl-LDO (11.48 m2/g). X-ray diffraction analysis revealed that CDs@MgAl-LDO maintained the "memory effect" of LDOs and could retrieve the original structure when dispersed in water. Moreover, the modified carbon dots change the intrinsically hydrophilic nature of LDOs and help to improve the affinity for organic contaminants, including both cationic and anionic dyes. The adsorption of dyes on CDs@MgAl-LDO followed a pseudo-second-order kinetic model with correlation coefficients (R2) ranging from 0.9901 to 0.9911 and exhibited Freundlich-type heterogeneous adsorption. It showed superior adsorption performance for three dyes, with the maximum adsorption capacity of 3628.9-5174.1 mg/g, thereby outperforming previously reported LDH-based adsorbents. This work developed a facile approach for preparing new carbon dots-LDH hybrids for the highly efficient removal of multiple dyes.
Collapse
Affiliation(s)
- Jiahui Ge
- Department of Analytical Chemistry, Jilin Institute of Chemical Technology, No. 45 Chengde Street, Jilin 132022, PR China
| | - Lili Lian
- Department of Analytical Chemistry, Jilin Institute of Chemical Technology, No. 45 Chengde Street, Jilin 132022, PR China.
| | - Xiyue Wang
- Department of Analytical Chemistry, Jilin Institute of Chemical Technology, No. 45 Chengde Street, Jilin 132022, PR China
| | - Xueling Cao
- Department of Analytical Chemistry, Jilin Institute of Chemical Technology, No. 45 Chengde Street, Jilin 132022, PR China
| | - Wenxiu Gao
- Department of Analytical Chemistry, Jilin Institute of Chemical Technology, No. 45 Chengde Street, Jilin 132022, PR China
| | - Dawei Lou
- Department of Analytical Chemistry, Jilin Institute of Chemical Technology, No. 45 Chengde Street, Jilin 132022, PR China.
| |
Collapse
|
13
|
Veeramuthu L, Venkatesan M, Benas JS, Cho CJ, Lee CC, Lieu FK, Lin JH, Lee RH, Kuo CC. Recent Progress in Conducting Polymer Composite/Nanofiber-Based Strain and Pressure Sensors. Polymers (Basel) 2021; 13:4281. [PMID: 34960831 PMCID: PMC8705576 DOI: 10.3390/polym13244281] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 12/01/2021] [Accepted: 12/01/2021] [Indexed: 01/11/2023] Open
Abstract
The Conducting of polymers belongs to the class of polymers exhibiting excellence in electrical performances because of their intrinsic delocalized π- electrons and their tunability ranges from semi-conductive to metallic conductive regime. Conducting polymers and their composites serve greater functionality in the application of strain and pressure sensors, especially in yielding a better figure of merits, such as improved sensitivity, sensing range, durability, and mechanical robustness. The electrospinning process allows the formation of micro to nano-dimensional fibers with solution-processing attributes and offers an exciting aspect ratio by forming ultra-long fibrous structures. This review comprehensively covers the fundamentals of conducting polymers, sensor fabrication, working modes, and recent trends in achieving the sensitivity, wide-sensing range, reduced hysteresis, and durability of thin film, porous, and nanofibrous sensors. Furthermore, nanofiber and textile-based sensory device importance and its growth towards futuristic wearable electronics in a technological era was systematically reviewed to overcome the existing challenges.
Collapse
Affiliation(s)
- Loganathan Veeramuthu
- Institute of Organic and Polymeric Materials, Research and Development Center of Smart Textile Technology, National Taipei University of Technology, Taipei 10608, Taiwan; (L.V.); (M.V.); (J.-S.B.)
| | - Manikandan Venkatesan
- Institute of Organic and Polymeric Materials, Research and Development Center of Smart Textile Technology, National Taipei University of Technology, Taipei 10608, Taiwan; (L.V.); (M.V.); (J.-S.B.)
| | - Jean-Sebastien Benas
- Institute of Organic and Polymeric Materials, Research and Development Center of Smart Textile Technology, National Taipei University of Technology, Taipei 10608, Taiwan; (L.V.); (M.V.); (J.-S.B.)
| | - Chia-Jung Cho
- Institute of Organic and Polymeric Materials, Research and Development Center of Smart Textile Technology, National Taipei University of Technology, Taipei 10608, Taiwan; (L.V.); (M.V.); (J.-S.B.)
| | - Chia-Chin Lee
- Department of Physical Medicine and Rehabilitation, Cheng Hsin General Hospital, Taipei 11220, Taiwan;
| | - Fu-Kong Lieu
- Department of Physical Medicine and Rehabilitation, Cheng Hsin General Hospital, Taipei 11220, Taiwan;
- Department of Physical Medicine and Rehabilitation, National Defense Medical Center, Taipei 11490, Taiwan
| | - Ja-Hon Lin
- Institute of Electro-Optical Engineering, National Taipei University of Technology, Taipei 10608, Taiwan;
| | - Rong-Ho Lee
- Department of Chemical Engineering, National Chung Hsing University, Taichung 40227, Taiwan;
| | - Chi-Ching Kuo
- Institute of Organic and Polymeric Materials, Research and Development Center of Smart Textile Technology, National Taipei University of Technology, Taipei 10608, Taiwan; (L.V.); (M.V.); (J.-S.B.)
| |
Collapse
|
14
|
Simultaneous removal of toxic Pb(II) ions, poly(acrylic acid) and Triton X-100 from their mixed solution using engineered biochars obtained from horsetail herb precursor – Impact of post-activation treatment. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2021.119297] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
|
15
|
Tian Y, Lu H, Hong H, Qian L, Yuan B, Liu J, Yan C. Potential and mechanism of glomalin-related soil protein on metal sequestration in mangrove wetlands affected by aquaculture effluents. JOURNAL OF HAZARDOUS MATERIALS 2021; 420:126517. [PMID: 34261031 DOI: 10.1016/j.jhazmat.2021.126517] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Revised: 06/24/2021] [Accepted: 06/25/2021] [Indexed: 06/13/2023]
Abstract
Aquaculture effluent discharge containing heavy metals affects estuarine mangrove wetlands. Glomalin-related soil protein (GRSP) is recalcitrant organic matter that can be trapped in mangrove wetlands and is critical to metal sequestration. However, studies on the effects of long-term aquaculture effluents on metal pollution in adjacent mangrove wetlands and the ecological role of GRSP are lacking. For the first time, we revealed the effects of discharge histories (0, 8, and 14 years) of shrimp pond effluents on metals (As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn), including the entire process from feed to metals binding with GRSP in mangrove soils. Results showed that mangrove soils receiving the effluents generally had higher or similar metal loadings compared to the control, and long-term effluent discharge increased the potential toxicity of the metals. Aquaculture feed could be a main source of metal input. Redundancy analysis indicated that 14-year effluent discharge increased the pH, bulk density, total nitrogen, and total phosphorus of mangrove soils, reducing the potential of GRSP-bound metals. Scanning electron microscopy and infrared spectroscopy characterisation revealed that effluent disturbances changed the surface morphology and functional group contents of GRSP. This study provides insights into using GRSP as an aquaculture pollution bioindicator.
Collapse
Affiliation(s)
- Yuan Tian
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, China
| | - Haoliang Lu
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, China
| | - Hualong Hong
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, China
| | - Lu Qian
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, China
| | - Bo Yuan
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, China
| | - Jingchun Liu
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, China
| | - Chongling Yan
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, China; State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361102, China.
| |
Collapse
|
16
|
Wiśniewska M, Wawrzkiewicz M, Onyszko M, Medykowska M, Nosal-Wiercińska A, Bogatyrov V. Carbon-Silica Composite as Adsorbent for Removal of Hazardous C.I. Basic Yellow 2 and C.I. Basic Blue 3 Dyes. MATERIALS (BASEL, SWITZERLAND) 2021; 14:3245. [PMID: 34208412 PMCID: PMC8231134 DOI: 10.3390/ma14123245] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Revised: 06/05/2021] [Accepted: 06/09/2021] [Indexed: 11/21/2022]
Abstract
Treatment of wastewaters containing hazardous substances such as dyes from the textile, paper, plastic and food industries is of great importance. Efficient technique for the removal of highly toxic organic dyes is adsorption. In this paper, adsorptive properties of the carbon-silica composite (C/SiO2) were evaluated for the cationic dyes C.I. Basic Blue 3 (BB3) and C.I. Basic Yellow 2 (BY2). The sorption capacities were determined as a function of temperature (924.6-1295.9 mg/g for BB3 and 716.3-733.2 mg/g for BY2 at 20-60 °C) using the batch method, and the Langmuir, Freundlich and Temkin isotherm models were applied for the equilibrium data evaluation using linear and non-linear regression. The rate of dye adsorption from the 100 mg/L solution was very fast, after 5 min. of phase contact time 98% of BB3 and 86% of BY2 was removed by C/SiO2. Presence of the anionic (SDS), cationic (CTAB) and non-ionic (Triton X-100) surfactants in the amount of 0.25 g/L caused decrease in BB3 and BY2 uptake. The electrokinetic studies, including determination of the solid surface charge density and zeta potential of the composite suspensions in single and mixed adsorbate systems, were also performed. It was shown that presence of adsorption layers changes the structure of the electrical double layer formed on the solid surface, based on the evidence of changes in ionic composition of both surface layer and the slipping plane area. The greatest differences between suspension with and without adsorbates was obtained in the mixed dye + SDS systems; the main reason for this is the formation of dye-surfactant complexes in the solution and their adsorption at the interface.
Collapse
Affiliation(s)
- Małgorzata Wiśniewska
- Department of Radiochemistry and Environmental Chemistry, Faculty of Chemistry, Institute of Chemical Sciences, Maria Curie- Sklodowska University in Lublin, M. Curie-Sklodowska Sq. 3, 20-031 Lublin, Poland;
| | - Monika Wawrzkiewicz
- Department of Inorganic Chemistry, Faculty of Chemistry, Institute of Chemical Sciences, Maria Curie-Sklodowska University in Lublin, M. Curie-Sklodowska Sq. 2, 20-031 Lublin, Poland; (M.W.); (M.O.)
| | - Magda Onyszko
- Department of Inorganic Chemistry, Faculty of Chemistry, Institute of Chemical Sciences, Maria Curie-Sklodowska University in Lublin, M. Curie-Sklodowska Sq. 2, 20-031 Lublin, Poland; (M.W.); (M.O.)
| | - Magdalena Medykowska
- Department of Radiochemistry and Environmental Chemistry, Faculty of Chemistry, Institute of Chemical Sciences, Maria Curie- Sklodowska University in Lublin, M. Curie-Sklodowska Sq. 3, 20-031 Lublin, Poland;
| | - Agnieszka Nosal-Wiercińska
- Department of Analytical Chemistry, Faculty of Chemistry, Institute of Chemical Sciences, Maria Curie-Sklodowska University in Lublin, M. Curie-Sklodowska Sq. 3, 20-031 Lublin, Poland;
| | - Viktor Bogatyrov
- Chuiko Institute of Surface Chemistry, National Academy of Sciences of Ukraine, General Naumov Street 17, 03164 Kyiv, Ukraine;
| |
Collapse
|
17
|
Simultaneous Removal of Pb 2+ and Zn 2+ Heavy Metals Using Fly Ash Na-X Zeolite and Its Carbon Na-X(C) Composite. MATERIALS 2021; 14:ma14112832. [PMID: 34070666 PMCID: PMC8198950 DOI: 10.3390/ma14112832] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 05/19/2021] [Accepted: 05/23/2021] [Indexed: 12/02/2022]
Abstract
Pure zeolite (Na-X) and a zeolite–carbon composite (Na-X(C)) were investigated as adsorbents of heavy metals—Pb2+ and Zn2+ from an aqueous solution. These materials were synthesized from fly ash—a waste from conventional hard coal combustion. Both solids were characterized using XRD, SEM-EDS, nitrogen adsorption/desorption, particle size and elemental composition analyses. The adsorption study was performed at pH 5 in the systems containing one or two adsorbates simultaneously. The obtained results showed that the pure zeolite was characterized by a more developed surface area (728 m2/g) than its carbon composite (272 m2/g), and the mean pore diameters were equal to 1.73 and 2.56 nm, respectively. The pure Na-X zeolite showed better adsorption properties towards heavy metals than its Na-X(C) composite, and Zn2+ adsorbed amounts were significantly higher than the Pb2+ ones (the highest experimental adsorption levels were: for Zn2+—656 and 600 mg/g, and for Pb2+—575 and 314 mg/g, on the Na-X and Na-X(C) surfaces, respectively). The zinc ions are exchanged with the cations inside the zeolite materials structure more effectively than lead ions with a considerably larger size. In the mixed systems, the competition between both heavy metals for access to the active sites on the adsorbent surface leads to the noticeable reduction in their adsorbed amounts. Moreover, the hydrochloric acid was a better desorbing agent for both heavy metals, especially Pb2+ one (desorption reached 78%), than sodium base (maximal desorption 25%).
Collapse
|
18
|
Szewczuk-Karpisz K, Tomczyk A, Celińska M, Sokołowska Z, Kuśmierz M. Carboxin and Diuron Adsorption Mechanism on Sunflower Husks Biochar and Goethite in the Single/Mixed Pesticide Solutions. MATERIALS 2021; 14:ma14102584. [PMID: 34065659 PMCID: PMC8157177 DOI: 10.3390/ma14102584] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 05/13/2021] [Accepted: 05/14/2021] [Indexed: 02/07/2023]
Abstract
The study focused on the adsorption mechanism of two selected pesticides: carboxin and diuron, on goethite and biochar, which were treated as potential compounds of mixed adsorbent. The authors also prepared a simple mixture of goethite and biochar and performed adsorption measurements on this material. The adsorbents were characterized by several methods, inter alia, nitrogen adsorption/desorption, Boehm titration, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The adsorption study included kinetics and equilibrium measurements, in the solution containing one or two pesticides simultaneously. The adsorption data were fitted to selected theoretical models (e.g., Langmuir, Freudlich, Redlich-Peterson, pseudo first-order and pseudo second-order equations). Based on the obtained results, it was stated that, among all tested adsorbents, biochar had the highest adsorption capacity relative to both carboxin and diuron. It equaled 0.64 and 0.52 mg/g, respectively. Experimental data were best fitted to the pseudo second-order and Redlich-Peterson models. In the mixed systems, the adsorption levels observed on biochar, goethite and their mixture were higher for diuron and lower for carboxin, compared to those noted in the single solutions. The presented results may enable the development of new mixed adsorbent for remediation of soils polluted with pesticides.
Collapse
Affiliation(s)
- Katarzyna Szewczuk-Karpisz
- Institute of Agrophysics, Polish Academy of Sciences, Doświadczalna 4, 20-290 Lublin, Poland; (A.T.); (M.C.); (Z.S.)
- Correspondence:
| | - Agnieszka Tomczyk
- Institute of Agrophysics, Polish Academy of Sciences, Doświadczalna 4, 20-290 Lublin, Poland; (A.T.); (M.C.); (Z.S.)
| | - Magdalena Celińska
- Institute of Agrophysics, Polish Academy of Sciences, Doświadczalna 4, 20-290 Lublin, Poland; (A.T.); (M.C.); (Z.S.)
| | - Zofia Sokołowska
- Institute of Agrophysics, Polish Academy of Sciences, Doświadczalna 4, 20-290 Lublin, Poland; (A.T.); (M.C.); (Z.S.)
| | - Marcin Kuśmierz
- Analytical Laboratory, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Sklodowska University, Maria Curie-Sklodowska Sq. 3, 20-031 Lublin, Poland;
| |
Collapse
|
19
|
Bai Y, Hong J. Preparation of a Novel Millet Straw Biochar-Bentonite Composite and Its Adsorption Property of Hg 2+ in Aqueous Solution. MATERIALS 2021; 14:ma14051117. [PMID: 33673689 PMCID: PMC7957562 DOI: 10.3390/ma14051117] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 02/20/2021] [Accepted: 02/22/2021] [Indexed: 12/17/2022]
Abstract
The remediation of mercury (Hg) contaminated soil and water requires the continuous development of efficient pollutant removal technologies. To solve this problem, a biochar–bentonite composite (CB) was prepared from local millet straw and bentonite using the solution intercalation-composite heating method, and its physical and chemical properties and micromorphology were then studied. The prepared CB and MB (modified biochar) had a maximum adsorption capacity for Hg2+ of 11.722 and 9.152 mg·g−1, respectively, far exceeding the corresponding adsorption value of biochar and bentonite (6.541 and 2.013 mg·g−1, respectively).The adsorption of Hg2+ on the CB was characterized using a kinetic model and an isothermal adsorption line, which revealed that the pseudo-second-order kinetic model and Langmuir isothermal model well represented the adsorption of Hg2+ on the CB, indicating that the adsorption was mainly chemical adsorption of the monolayer. Thermodynamic experiments confirmed that the adsorption process of Hg2+ by the CB was spontaneous and endothermic. Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and a thermogravimetric analysis (TGA) showed that after Hg2+ was adsorbed by CB, functional groups, such as the –OH group (or C=O, COO–, C=C) on the CB, induced complexation between Hg and –O–, and part of Hg (ii) was reduced Hg (i), resulting in the formation of single or double tooth complexes of Hg–O– (or Hg–O–Hg). Therefore, the prepared composite (CB) showed potential application as an excellent adsorbent for removing heavy metal Hg2+ from polluted water compared with using any one material alone.
Collapse
|