1
|
Seifikar F, Habibi-Yangjeh A. Floating photocatalysts as promising materials for environmental detoxification and energy production: A review. CHEMOSPHERE 2024; 355:141686. [PMID: 38513952 DOI: 10.1016/j.chemosphere.2024.141686] [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: 01/07/2024] [Revised: 03/08/2024] [Accepted: 03/10/2024] [Indexed: 03/23/2024]
Abstract
The oxygenation process of the catalyst surface, the incident-light harvesting capability, and facile recycling of utilized photocatalysts play key role in the outstanding photocatalytic performances. The typical existing photocatalysts in powder form have many drawbacks, such as difficult separation from the treated water, insufficient surface oxygenation, poor active surface area, low incident-light harvesting ability, and secondary pollution of the environment. A great number of scientific works introduced novel and fresh ideas related to designing floating photocatalytic systems by immobilizing highly active photocatalysts onto a floatable substrate. Thanks to direct contact with the illuminated light and oxygen molecules in the interface of water/air, the photocatalytic performance is maximized through production of more reactive species, employed in the photocatalytic reactions. Furthermore, facile recovering of the utilized photocatalysts for next processes avoids secondary pollution as well as diminishes the process's price. This review highlights the performance of developed floating photocatalysts for diverse applications. Furthermore, different floating substrates and possible mechanisms in floating photocatalysts are briefly mentioned. In addition, several emerging self-floating photocatalytic systems are taken attention and discussed. Specially, coupling photo-thermal and photocatalytic effects seems to be a good strategy for introducing a new class of floating photocatalyst to utilize the free, abundant, and green sunlight energy for the aims of water desalination and purification. Despite of a large number of attempts about the floating photocatalysts, there are still plenty of rooms for more in-depth research to be carried out for attaining the required characteristics of the large scale utilizations of these materials.
Collapse
Affiliation(s)
- Fatemeh Seifikar
- Department of Chemistry, Faculty of Science, University of Mohaghegh Ardabili, Ardabil, Iran
| | - Aziz Habibi-Yangjeh
- Department of Chemistry, Faculty of Science, University of Mohaghegh Ardabili, Ardabil, Iran.
| |
Collapse
|
2
|
Fu X, Zhou G, Li J, Yao Q, Han Z, Yang R, Chen X, Wang Y. Critical review on modified floating photocatalysts for emerging contaminants removal from landscape water: problems, methods and mechanism. CHEMOSPHERE 2023; 341:140043. [PMID: 37660787 DOI: 10.1016/j.chemosphere.2023.140043] [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: 05/22/2023] [Revised: 07/13/2023] [Accepted: 08/31/2023] [Indexed: 09/05/2023]
Abstract
Due to the disorderly discharge in modern production and daily life of people, emerging contaminants(ECs) began to appear in landscape water, and have become a key public concern. Because of the unique characteristics of landscape water, it is difficult to efficiently remove ECs either by natural purification or by traditional large-scale sewage treatment facilities. The ideal purification method is to remove them while maintaining a beautiful environment. Possessing the feature of low-density, floating photocatalysts could harvest sufficient light on the surface of the water for photocatalytic degradation, which may be an important supplement for ECs treatment in landscape water. This paper gave a review related to floating photocatalysts and proposed an idea of combining floating photocatalysts to construct bionic photocatalytic materials for contaminative landscape water treatment. Six types of common floating substrates and corresponding applications for floating photocatalysts were concluded in this paper, and the main problem leading to the low efficiency of photocatalysts and three corresponding three improvement strategies were discussed. Besides, the modification mechanisms of photocatalysts were discussed thoroughly. On this basis, the engineering application prospects of bionic photocatalytic materials were proposed to remove ECs in landscape water.
Collapse
Affiliation(s)
- Xiaoning Fu
- College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao, China.
| | - Guangzhu Zhou
- College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao, China.
| | - Jianping Li
- China Testing & Certification International Group Qingdao Jingcheng Testing Co., Ltd., Qingdao, 266426, China.
| | - Qiuhui Yao
- The Third Exploration Team, Shandong Bureau of Coal Geology, Tai'an, 271000, China.
| | - Zuozhen Han
- Shandong Provincial Key Laboratory of Depositional Mineralization and Sedimentary Minerals, College of Earth Science and Engineering, Shandong University of Science and Technology, Qingdao, China.
| | - Rongchao Yang
- College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao, China.
| | - Xi Chen
- College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao, China.
| | - Yuanhao Wang
- College of Safety and Environmental Engineering, Shandong University of Science and Technology, Qingdao, China.
| |
Collapse
|
3
|
Sun S, Tang Q, Xu H, Gao Y, Zhang W, Zhou L, Li Y, Wang J, Song C. A comprehensive review on the photocatalytic inactivation of Microcystis aeruginosa: Performance, development, and mechanisms. CHEMOSPHERE 2023; 312:137239. [PMID: 36379431 DOI: 10.1016/j.chemosphere.2022.137239] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 11/01/2022] [Accepted: 11/11/2022] [Indexed: 06/16/2023]
Abstract
Harmful algae blooms (HABs), caused by severe eutrophication and extreme weather, have spread all over the world, posing adverse effects on eco-environment and human health. Microcystis aeruginosa is the dominant harmful cyanobacterial species when HABs occur, and the toxic metabolites produced by it, microcystins, are even fatal to humans. Photocatalytic technology has received wide attention from researchers for its clean and energy-efficient features, while the basic mechanisms and modification methods of photocatalysts have also been widely reported. In recent years, photocatalytic technology has shown great promise in the inhibition of HABs. In this article, we systematically reviewed the progress in photocatalytic performance and algae removal efficiency, discuss the damage mechanisms of photocatalysts for algae removal, including physical damage and various oxidative stresses, and also explore the degradation rates and possible pathways of microcystins. It can be concluded that during the photocatalytic process, the cytoarchitectural integrity of algae cells was damaged, a variety of important protein and enzyme systems were disrupted, and the antioxidant systems collapsed due to the continuous attack of ROS, which adversely affected the normal physiological activities and growth, resulting in the inactivation of algae cells. Moreover, photocatalysts have a degrading effect on microcystins, thus reducing the adverse effects of HAB. Finally, a brief summary of future research priorities regarding the photocatalytic degradation of algae cells is presented. This study helps to enhance the understanding of the destruction mechanism of Microcystis aeruginosa during the photocatalytic process, and provides a reference for the photodegradation of HAB in water bodies.
Collapse
Affiliation(s)
- Shiquan Sun
- School of Hydraulic and Environmental Engineering, Changsha University of Science & Technology, Changsha, 410114, China; Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province, Changsha, 410114, China.
| | - Qingxin Tang
- School of Hydraulic and Environmental Engineering, Changsha University of Science & Technology, Changsha, 410114, China; Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province, Changsha, 410114, China
| | - Hui Xu
- Shenzhen General Integrated Transportation and Municipal Engineering Design & Research Institute Co. Ltd., Shenzhen, 518000, China.
| | - Yang Gao
- School of Hydraulic and Environmental Engineering, Changsha University of Science & Technology, Changsha, 410114, China; Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province, Changsha, 410114, China
| | - Wei Zhang
- School of Hydraulic and Environmental Engineering, Changsha University of Science & Technology, Changsha, 410114, China; Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province, Changsha, 410114, China
| | - Lean Zhou
- School of Hydraulic and Environmental Engineering, Changsha University of Science & Technology, Changsha, 410114, China; Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province, Changsha, 410114, China
| | - Yifu Li
- School of Hydraulic and Environmental Engineering, Changsha University of Science & Technology, Changsha, 410114, China; Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province, Changsha, 410114, China
| | - Jinting Wang
- School of Hydraulic and Environmental Engineering, Changsha University of Science & Technology, Changsha, 410114, China; Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province, Changsha, 410114, China
| | - Chuxuan Song
- School of Hydraulic and Environmental Engineering, Changsha University of Science & Technology, Changsha, 410114, China; Key Laboratory of Dongting Lake Aquatic Eco-Environmental Control and Restoration of Hunan Province, Changsha, 410114, China
| |
Collapse
|
4
|
Qin Y, Yang B, Li H, Ma J. Immobilized BiOCl 0.75I 0.25/g-C 3N 4 nanocomposites for photocatalytic degradation of bisphenol A in the presence of effluent organic matter. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 842:156828. [PMID: 35760181 DOI: 10.1016/j.scitotenv.2022.156828] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 06/11/2022] [Accepted: 06/15/2022] [Indexed: 06/15/2023]
Abstract
The BiOCl0.75I0.25/g-C3N4 nanosheet (BCI-CN) was successfully immobilized on polyolefin polyester fiber (PPF) through the hydrothermal method. The novel immobilized BiOCl0.75I0.25/g-C3N4 nanocomposites (BCI-CN-PPF) were characterized by scanning electron microscope (SEM), energy dispersive spectroscopy EDS, X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and UV-vis diffuse reflectance spectroscopy (UV-vis DRS) to confirm that BCI-CN was successfully immobilized on PPF with abundant oxygen vacancies reserved. Under simulated solar light irradiation, 100 % of bisphenol A (BPA) with an initial concentration of 10 mg·L-1 was degraded by BCI-CN-PPF (0.2 g·L-1 of BCI-CN immobilized) after 60 min. A similar photocatalytic efficiency of BPA was obtained in the presence of effluent organic matter (EfOM). The photocatalytic degradation of BPA was not affected by EfOM <5 mg-C/L. In comparison, the photocatalytic performance was considerably inhibited by EfOM with a concentration of 10 mg-C/L. Furthermore, photogenerated holes and superoxide radicals predominated in the photocatalytic degradation processes of BPA. The total organic carbon (TOC) removal efficiencies of BPA and EfOM were 75.2 % and 50 % in the BCI-CN-PPF catalytic system. The BPA removal efficiency of 94.9 % was still achieved in the eighth cycle of repeated use. This study provides a promising immobilized nanocomposite with high photocatalytic activity and excellent recyclability and reusability for practical application in wastewater treatment.
Collapse
Affiliation(s)
- Yuyang Qin
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China
| | - Biqi Yang
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China
| | - Hongjing Li
- Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China.
| | - Jun Ma
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| |
Collapse
|
5
|
Bhatti MA, Gilani SJ, Shah AA, Channa IA, Almani KF, Chandio AD, Halepoto IA, Tahira A, Bin Jumah MN, Ibupoto ZH. Effective Removal of Methylene Blue by Surface Alteration of TiO 2 with Ficus Carica Leaf Extract under Visible Light. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:nano12162766. [PMID: 36014631 PMCID: PMC9416792 DOI: 10.3390/nano12162766] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 07/27/2022] [Accepted: 08/05/2022] [Indexed: 05/17/2023]
Abstract
The present study describes the use of a leaf extract from Ficus carica as a source of natural antioxidants for the surface alteration of bulk titanium dioxide (TiO2) in two steps. First, the hydro-thermal treatment of the bulk TiO2 material was carried out and followed by thermal annealing at 300 °C for 3 h in air. The role of the leaf extract of Ficus carica on the performance of the bulk TiO2 material for the removal of methylene blue (MB) was also studied. Various analytical techniques such as powder X-ray diffraction (XRD), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) were used to explore the crystalline structure, morphology, and composition. The bulk TiO2 material after the leaf-extract treatment exhibited mixed anatase and rutile phases, a flower-like morphology, and Ti, O, and C were its main elements. The average crystallite size was also calculated, and the obtained values for the bulk TiO2 material, 18.11 nm, and the treated bulk TiO2 material with various amounts, 5, 10, and 15 mL, of leaf extract were 16.4, 13.16, and 10.29 nm respectively. Moreover, Fourier-transform infrared spectroscopy validated the typical metal-oxygen bonds and strengthened the XRD results. The bulk TiO2 material chemically treated with Ficus carica has shown outstanding activity towards the degradation of MB under sunlight. The 15 mL of Ficus carica extract significantly enhanced the photocatalytic activity of the bulk TiO2 material towards the degradation of MB. The dye degradation efficiency was found to be 98.8%, which was experimentally proven by the Fourier Transform Infrared spectroscopoyy (FTIR) analysis. The obtained performance of the bulk TiO2 material with Ficus carica revealed excellent surface modifying properties for poorly-performing photocatalysts towards the degradation of synthetic dyes when used in their pristine form. The presented approach suggests that Ficus carica could be of great interest for tuning the surface properties of materials, either in the form of nano-size or bulk-phase in a particular application.
Collapse
Affiliation(s)
- Muhammad Ali Bhatti
- Institute of Environmental Sciences, University of Sindh Jamshoro, Jamshoro 76080, Sindh, Pakistan
| | - Sadaf Jamal Gilani
- Department of Basic Health Sciences, Preparatory Year, Princess Nourah Bint Abdulrahman University, Riyadh 11671, Saudi Arabia
| | - Aqeel Ahmed Shah
- Thin Film and Wet Chemistry Lab, Department of Metallurgical Engineering, NED University of Engineering and Technology, Karachi 75270, Sindh, Pakistan
| | - Iftikhar Ahmed Channa
- Thin Film and Wet Chemistry Lab, Department of Metallurgical Engineering, NED University of Engineering and Technology, Karachi 75270, Sindh, Pakistan
| | - Khalida Faryal Almani
- Institute of Environmental Sciences, University of Sindh Jamshoro, Jamshoro 76080, Sindh, Pakistan
| | - Ali Dad Chandio
- Thin Film and Wet Chemistry Lab, Department of Metallurgical Engineering, NED University of Engineering and Technology, Karachi 75270, Sindh, Pakistan
| | - Imran Ali Halepoto
- Institute of Physics, University of Sindh, Jamshoro 76080, Sindh, Pakistan
| | - Aneela Tahira
- Dr. M.A Kazi Institute of Chemistry, University of Sindh, Jamshoro 76080, Sindh, Pakistan
| | - May Nasser Bin Jumah
- Biology Department, College of Science, Princess Nourah Bint Abdulrahman University, Riyadh 11671, Saudi Arabia
- Environment and Biomaterial Unit, Health Sciences Research Center, Princess Nourah Bint Abdulrahman University, Riyadh 11671, Saudi Arabia
- Saudi Society for Applied Science, Princess Nourah Bint Abdulrahman University, Riyadh 11671, Saudi Arabia
| | - Zafar Hussain Ibupoto
- Dr. M.A Kazi Institute of Chemistry, University of Sindh, Jamshoro 76080, Sindh, Pakistan
- Correspondence:
| |
Collapse
|
6
|
Floating Carbon-Doped TiO2 Photocatalyst with Metallic Underlayers Investigation for Polluted Water Treatment under Visible-Light Irradiation. Catalysts 2021. [DOI: 10.3390/catal11121454] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
In the current study, we analysed the influence of metallic underlayers on carbon-doped TiO2 films for RhB decomposition and Salmonella typhimurium inactivation under visible-light irradiation. All the experiments were divided into two parts. First, layered M/C-doped-TiO2 film structures (M = Ni, Nb, Cu) were prepared by magnetron sputtering technique on borosilicate glass substrates in the two-step deposition process. The influence of metal underlayer on the formation of the carbon-doped TiO2 films was characterised by X-ray diffractometer, scanning electron microscope, and atomic force microscope. The comparison between the visible-light assisted photocatalytic activity of M/C-doped TiO2 structures was performed by the photocatalytic bleaching tests of Rhodamine B dye aqueous solution. The best photocatalytic performance was observed for Ni/C-doped-TiO2 film combination. During the second part of the study, the Ni/C-doped-TiO2 film combination was deposited on high-density polyethylene beads which were selected as a floating substrate. The morphology and surface chemical analyses of the floating photocatalyst were performed. The viability and membrane permeability of Salmonella typhimurium were tested in cycling experiments under UV-B and visible-light irradiation. Three consecutive photocatalytic treatments of fresh bacteria suspensions with the same set of floating photocatalyst showed promising results, as after the third 1 h-long treatment bacteria viability was still reduced by 90% and 50% for UV-B and visible-light irradiation, respectively. The membrane permeability and ethidium fluorescence results suggest that Ni underlayer might have direct and indirect effect on the bacteria inactivation process. Additionally, relatively low loss of the photocatalyst efficiency suggests that floating C-doped TiO2 photocatalyst with the Ni underlayer might be seen as the possible solution for the used photocatalyst recovery issue.
Collapse
|
7
|
Photocatalytic Inactivation of Salmonella typhimurium by Floating Carbon-Doped TiO 2 Photocatalyst. MATERIALS 2021; 14:ma14195681. [PMID: 34640080 PMCID: PMC8510230 DOI: 10.3390/ma14195681] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 09/17/2021] [Accepted: 09/25/2021] [Indexed: 01/12/2023]
Abstract
Photocatalysis application is considered as one of the most highly promising techniques for the reduction in wastewater pollution. However, the majority of highly efficient photocatalyst materials are obtained as fine powders, and this causes a lot of photocatalyst handling and reusability issues. The concept of the floating catalyst proposes the immobilization of a photocatalytic (nano)material on relatively large floating substrates and is considered as an encouraging way to overcome some of the most challenging photocatalysis issues. The purpose of this study is to examine floating photocatalyst application for Salmonella typhimurium bacteria inactivation in polluted water. More specifically, high-density polyethylene (HDPE) beads were used as a photocatalyst support for the immobilization of carbon-doped TiO2 films forming floating photocatalyst structures. Carbon-doped TiO2 films in both amorphous and anatase forms were deposited on HDPE beads using the low-temperature magnetron sputtering technique. Bacteria inactivation, together with cycling experiments, revealed promising results by decomposing more than 95% of Salmonella typhimurium bacteria in five consecutive treatment cycles. Additionally, a thorough analysis of the deposited carbon-doped TiO2 film was performed including morphology, elemental composition and mapping, structure, and depth profiling. The results demonstrate that the proposed method is a suitable technique for the formation of high-quality photocatalytic active films on thermal-sensitive substrates.
Collapse
|
8
|
Varnagiris S, Urbonavicius M, Sakalauskaite S, Daugelavicius R, Pranevicius L, Lelis M, Milcius D. Floating TiO 2 photocatalyst for efficient inactivation of E. coli and decomposition of methylene blue solution. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 720:137600. [PMID: 32135289 DOI: 10.1016/j.scitotenv.2020.137600] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Revised: 02/14/2020] [Accepted: 02/25/2020] [Indexed: 06/10/2023]
Abstract
The anatase phase TiO2 films with nanocrystalline structure were successfully deposited on a water-floating non-expanded polystyrene (PS) beads via magnetron sputtering. The combination of UVB light and PS beads with TiO2 film was used for decomposition of methylene blue as well as inactivation tests for intact and EDTA-treated Escherichia coli bacteria. Crystal structure, elemental composition, elemental mapping, surface morphology and chemical bonds of TiO2 film were investigated. E. coli inactivation experiments showed that such floating photocatalyst could destroy >90% bacteria in 45 min under UVB irradiation. Results demonstrated that combination of TiO2 and UVB light leads to disruption of the outer membrane which causes effective inactivation of E. coli bacteria.
Collapse
Affiliation(s)
- Sarunas Varnagiris
- Center for Hydrogen Energy Technologies, Lithuanian Energy Institute, Kaunas, Lithuania.
| | - Marius Urbonavicius
- Center for Hydrogen Energy Technologies, Lithuanian Energy Institute, Kaunas, Lithuania
| | - Sandra Sakalauskaite
- Department of Biochemistry, Faculty of Natural Sciences, Vytautas Magnus University, Kaunas, Lithuania
| | - Rimantas Daugelavicius
- Department of Biochemistry, Faculty of Natural Sciences, Vytautas Magnus University, Kaunas, Lithuania
| | | | - Martynas Lelis
- Center for Hydrogen Energy Technologies, Lithuanian Energy Institute, Kaunas, Lithuania
| | - Darius Milcius
- Center for Hydrogen Energy Technologies, Lithuanian Energy Institute, Kaunas, Lithuania
| |
Collapse
|
9
|
Zhao Z, Omer AA, Qin Z, Osman S, Xia L, Singh RP. Cu/N-codoped TiO 2 prepared by the sol-gel method for phenanthrene removal under visible light irradiation. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:17530-17540. [PMID: 31317433 DOI: 10.1007/s11356-019-05787-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2019] [Accepted: 06/18/2019] [Indexed: 06/10/2023]
Abstract
Cu/N-codoped TiO2 nanoparticles were prepared by the modified sol-gel method, to study its efficiency for the removing of polyaromatic hydrocarbon (phenanthrene) from an aqueous solution. Urea and copper sulfate pentahydrate were used as sources of doping element for Cu/N-codoped TiO2, respectively. The characterizations of the nanoparticles were done by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and UV-vis diffuse reflectance spectra. XRD revealed that all the nanoparticles were indexed to the anatase phase structure, with crystallite size range from 11 to 30 nm, which decreased with the doping of copper and nitrogen. The photocatalytic activities of Cu/N-codoped TiO2 showed the highest activities than other TiO2 nanoparticles (TiO2 and N-doped TiO2). The photodegradation efficiency of Cu/N-codoped TiO2 on phenanthrene under visible light irradiation was slightly higher (96%) comparing to UV light irradiation (94%). Cu/N-codoped TiO2 was found to be very efficient and economical for phenanthrene removal, because the smallest amount of Cu/N-codoped TiO2 exhibited the best removal efficiency on phenanthrene.
Collapse
Affiliation(s)
- Zhenhua Zhao
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, People's Republic of China
| | - Abduelrahman Adam Omer
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, People's Republic of China.
- Department of Civil Engineering, College of Engineering Science, Nyala University, Nyala, Sudan.
| | - Zhirui Qin
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, People's Republic of China
| | - Salaheldein Osman
- Department of Civil Engineering, College of Engineering Science, Nyala University, Nyala, Sudan
- Water Harvesting center, Nyala University, Nyala, Sudan
| | - Liling Xia
- Nanjing Institute of Industry Technology, People's Republic of, Nanjing, 210016, China
| | | |
Collapse
|
10
|
SiO 2/TiO 2 Composite Coating on Light Substrates for Photocatalytic Decontamination of Water. J CHEM-NY 2019. [DOI: 10.1155/2019/2634398] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In this study, we describe synthesis and characterization of a floating photocatalyst for water treatment consisting of a light substrate coated by SiO2/TiO2 composite. Three supports of natural origin were used: natural cork, expanded clay (Liapor), and volcanic porous glass (Sorbix). The photoactivity of the coated supports was tested in a laboratory photoreactor, with Liapor being the most photoactive support with good mechanical stability. The corresponding rate constant for the degradation of a model pollutant, 4-chlorophenol, was 7.8 × 10−5 s−1. Detail characterization of the coated Liapor was obtained by XRF, SEM/EDX, and UV-Vis diffuse reflectance spectroscopy, and surface area measurements. Outdoor experiments were carried out with calcined Liapor and oxalic acid or methylene blue under sunlight on pilot reactors in the Czech Republic and Vietnam. We demonstrated satisfactory photocatalytic activity, long-term stability, and reusability of the new floating photocatalyst. The photoefficiency to mineralize oxalic acid in water under sunlight was estimated as 6.7% under the applied conditions.
Collapse
|
11
|
Mushtaq F, Zahid M, Bhatti IA, Nasir S, Hussain T. Possible applications of coal fly ash in wastewater treatment. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 240:27-46. [PMID: 30928793 DOI: 10.1016/j.jenvman.2019.03.054] [Citation(s) in RCA: 65] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 02/08/2019] [Accepted: 03/12/2019] [Indexed: 05/19/2023]
Abstract
Management of coal fly ash as a particulate byproduct of coal burning has become an issue to be solved right away due to environmental concerns related to soil, water, and air pollution. Many attempts have been made by researchers for the conversion of coal fly ash into useful products while searching feasible avenues for its sustainable utilization. Wastewater remediation using coal fly ash is one such attempt solving both waste management and water quality issues. The characteristics like morphology, surface area, porosity, and chemical composition (silica, alumina, iron oxide, titania, etc.) make coal fly ash amenable material for potential application in wastewater treatment. Few reports have summarized the coal fly ash utilization in wastewater treatment but solely discussed the adsorption. Besides adsorption, the current paper aims to highlight the possibilities of using coal fly ash in wastewater treatment by different technologies that extend the utilization scope in the domains of filtration, Fenton process, photocatalysis, and coagulation. The promising use of coal fly ash as an adsorbent, membrane filter, Fenton catalyst, photocatalyst, and as an integral part of these structures is reviewed. Finally, the current trends and future prospects on utilization modes of coal fly ash in wastewater treatment are stated.
Collapse
Affiliation(s)
- Farwa Mushtaq
- Department of Chemistry, University of Agriculture, Faisalabad, 38040 Pakistan
| | - Muhammad Zahid
- Department of Chemistry, University of Agriculture, Faisalabad, 38040 Pakistan.
| | - Ijaz Ahmad Bhatti
- Department of Chemistry, University of Agriculture, Faisalabad, 38040 Pakistan
| | - Saqib Nasir
- Pakistan Science Foundation,1-Constiution Avenue G-5/2, Islamabad, Pakistan
| | - Tajamal Hussain
- Institute of Chemistry, University of the Punjab, Lahore, Pakistan
| |
Collapse
|
12
|
Wang X, Wang J, Zhang J, Louangsouphom B, Song J, Wang X, Zhao J. Synthesis of expanded graphite C/C composites (EGC) based Ni-N-TiO 2 floating photocatalysts for in situ adsorption synergistic photocatalytic degradation of diesel oil. J Photochem Photobiol A Chem 2017. [DOI: 10.1016/j.jphotochem.2017.07.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
13
|
Interaction of New-Developed TiO₂-Based Photocatalytic Nanoparticles with Pathogenic Microorganisms and Human Dermal and Pulmonary Fibroblasts. Int J Mol Sci 2017; 18:ijms18020249. [PMID: 28125053 PMCID: PMC5343786 DOI: 10.3390/ijms18020249] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 01/13/2017] [Accepted: 01/16/2017] [Indexed: 01/20/2023] Open
Abstract
TiO2-based photocatalysts were obtained during previous years in order to limit pollution and to ease human daily living conditions due to their special properties. However, obtaining biocompatible photocatalysts is still a key problem, and the mechanism of their toxicity recently received increased attention. Two types of TiO2 nanoparticles co-doped with 1% of iron and nitrogen (TiO2-1% Fe–N) atoms were synthesized in hydrothermal conditions at pH of 8.5 (HT1) and 5.5 (HT2), and their antimicrobial activity and cytotoxic effects exerted on human pulmonary and dermal fibroblasts were assessed. These particles exhibited significant microbicidal and anti-biofilm activity, suggesting their potential application for microbial decontamination of different environments. In addition, our results demonstrated the biocompatibility of TiO2-1% Fe–N nanoparticles at low doses on lung and dermal cells, which may initiate oxidative stress through dose accumulation. Although no significant changes were observed between the two tested photocatalysts, the biological response was cell type specific and time- and dose-dependent; the lung cells proved to be more sensitive to nanoparticle exposure. Taken together, these experimental data provide useful information for future photocatalytic applications in the industrial, food, pharmaceutical, and medical fields.
Collapse
|