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Rameshkumar S, Henderson R, Padamati RB. Improved Surface Functional and Photocatalytic Properties of Hybrid ZnO-MoS 2-Deposited Membrane for Photocatalysis-Assisted Dye Filtration. MEMBRANES 2020; 10:membranes10050106. [PMID: 32455647 PMCID: PMC7281520 DOI: 10.3390/membranes10050106] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Revised: 05/15/2020] [Accepted: 05/18/2020] [Indexed: 11/16/2022]
Abstract
The synergistic mechanism of photocatalytic-assisted dye degradation has been demonstrated using a hybrid ZnO-MoS2-deposited photocatalytic membrane (PCM). Few layers of MoS2 sheets were produced using the facile and efficient surfactant-assisted liquid-phase exfoliation method. In this process, hydrophilic moieties of an anionic surfactant were adsorbed on the surface of MoS2, which aided exfoliation and promoted a stable dispersion due to the higher negative zeta potential of the exfoliated MoS2 sheets. Further, the decoration of ZnO on the exfoliated MoS2 sheets offered a bandgap energy reduction to about 2.77 eV, thus achieving an 87.12% degradation of methylene blue (MB) dye within 15 min of near UV-A irradiation (365 nm), as compared with pristine ZnO achieving only 56.89%. The photocatalysis-enhanced membrane filtration studies on the ZnO-MoS2 PCM showed a complete removal of MB dye (~99.95%). The UV-assisted dye degradation on the ZnO-MoS2 PCM offered a reduced membrane resistance, with the permeate flux gradually improving with the increase in the UV-irradiation time. The regeneration of the active ZnO-MoS2 layer also proved to be quite efficient with no compromise in the dye removal efficiency.
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Affiliation(s)
- Saranya Rameshkumar
- AMBER Centre, CRANN Institute, Trinity College Dublin, Dublin 2, Ireland;
- BiOrbic—Bioeconomy SFI Research Centre, University College Dublin, Belfield, Dublin 4, Ireland
- School of Physics, Trinity College Dublin, Dublin 2, Ireland
| | - Rory Henderson
- School of Physics, Trinity College Dublin, Dublin 2, Ireland
- School of Chemistry, Trinity College Dublin, Dublin 2, Ireland;
| | - Ramesh Babu Padamati
- AMBER Centre, CRANN Institute, Trinity College Dublin, Dublin 2, Ireland;
- BiOrbic—Bioeconomy SFI Research Centre, University College Dublin, Belfield, Dublin 4, Ireland
- School of Physics, Trinity College Dublin, Dublin 2, Ireland
- School of Chemistry, Trinity College Dublin, Dublin 2, Ireland;
- Correspondence:
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Guezzen B, Adjdir M, Medjahed B, Didi MA, Weidler PG. Kinetic study and Box–Behnken design approach to optimize the sorption process of toxic azo dye onto organo-modified bentonite. CAN J CHEM 2020. [DOI: 10.1139/cjc-2019-0393] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Kinetic study was applied for sodium bentonite (Na-B) and hexadecylpyridinium bentonite (HDP-B) under different amounts, namely 50% (50HDP-B), 100% (100HDP-B), and 200% (200HDP-B) with respect to cation exchange capacity (CEC). Pseudo first-order and pseudo second-order kinetic models were performed to optimize the sorption of Congo red (CR) dye from aqueous solution. The experimental data fit the pseudo second order kinetic model well. The sorption capacity (qe) of CR dye by the organo-bentonites at equilibrium was 36.0 mg g−1 (72.1%) for 50HDP-B, 48.05 mg g−1 (96.1%) for 100HDP-B, and 49.2 mg g−1 (98.4%) for 200HDP-B. These results were considerably higher than that found by Na-B. Response surface methodology with three-variable, three-level Box–Behnken design was applied for 100HDP-B to describe the removal of CR dye. The effects of three variables, namely temperature, adsorbent dosage, and initial dye concentration, were studied. Predicted values of adsorption efficiency were found to be in good agreement with the obtained experimental values (R2 = 0.97). A second-order polynomial model successfully described the effects of independent variables on the CR dye removal. At the optimized condition, the toxic azo dye could be quantitatively removed from aqueous solution. The results of the present study suggest that the organo-bentonite can be used as an efficient sorbent for dye removal from aqueous solution.
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Affiliation(s)
- Brahim Guezzen
- Laboratory of Separation and Purification Technology, Department of Chemistry, Faculty of Sciences, Tlemcen University, Box 119, Algeria
- Department of Process Engineering, Faculty of Technology, Dr. Moulay Tahar University, Saida, Algeria
| | - Mehdi Adjdir
- Department of Process Engineering, Faculty of Technology, Dr. Moulay Tahar University, Saida, Algeria
- Chemistry of Oxydic and Organic Interfaces, Karlsruher Institut für Technologie (KIT)/Campus Nord, Hermann-von-Helmholtz-Platz 1, Germany
| | - Baghdad Medjahed
- Laboratory of Separation and Purification Technology, Department of Chemistry, Faculty of Sciences, Tlemcen University, Box 119, Algeria
- Department of Process Engineering, Faculty of Technology, Dr. Moulay Tahar University, Saida, Algeria
| | - Mohamed A. Didi
- Laboratory of Separation and Purification Technology, Department of Chemistry, Faculty of Sciences, Tlemcen University, Box 119, Algeria
| | - Peter G. Weidler
- Chemistry of Oxydic and Organic Interfaces, Karlsruher Institut für Technologie (KIT)/Campus Nord, Hermann-von-Helmholtz-Platz 1, Germany
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