Post-synthesis plasma processing and activation of TiO2 photocatalyst for the removal of synthetic dyes from industrial wastewater

Abstract

In this study, TiO 2 nanopowders were prepared by combining the surfactant assisted sol-gel method with microwave plasma calcination. Plasma calcination was performed just for 20-30 min for reducing the calcination time and ensuring the energy efficient synthesis of photocatalyst. The mixed anatase-rutile phased TiO 2 nanoparticles were obtained under these synthesis conditions. The band gap energy of the photocatalyst decreased by 40% on microwave plasma calcination. The surfactants were found to be ineffective on phase transformations of synthesized TiO 2 . FTIR analysis confirmed the absorption of O-Ti-O band stretching between 415 and 420 cm −1 . The hydroxyl bands (OH) were observed to be less stretched after plasma calcination. The conventionally calcined HA-Ti, NA-Ti and MS-Ti samples showed band gap energies of 5.09 eV, 4.88 eV and 5.06 eV, respectively. The band gap energy of plasma calcined MTHA-Ti, MTNNA-Ti and MTMS-Ti samples was calculated about 4.92 eV, 3.11 eV and 4.96 eV, respectively. The combined effect of photocatalyst, plasma reactive species and UV radiations promoted the degradation efficiency of the methylene blue dye. Under DC plasma jet exposure, the maximum degradation efficiency of 95% was achieved after 30 min of plasma exposure time. The catalyst retained about 93-95% degradation efficiency after five cycles of dye degradation.

Statistically Optimized Production of Saccharides Stabilized Silver Nanoparticles Using Liquid–Plasma Reduction Approach for Antibacterial Treatment of Water

“…Various methodologies have been reported in the literature to synthesize metal nanoparticles, including hydrothermal method [ 6 ], sol-gel method [ 7 ], photodetection technique [ 8 ], ultraviolet irradiation method [ 9 ], electrochemical technique [ 10 ], porous materials template [ 11 ], solvothermal method [ 12 ], chemical synthesis [ 13 ], microwave plasma treatment [ 14 ], polyol process [ 15 ], green synthesis [ 16 , 17 ] coaxial electro-spinning [ 18 ] and liquid plasma interaction technique [ 19 ]. Each approach has its own set of advantages and disadvantages, including differences in process cost, quantity, functionality and particle size distribution.…”

Current Trend of MOFs Incorporated Membranes for Advanced Wastewater Treatment

“…tremendously danger the water ecosystem and human health (Wagner et al, 2021;Wibowo et al, 2021). The most commonly encountered POPs in wastewater are synthetic dyes (Shukrullah et al, 2021), agricultural waste such as pesticides and herbicides (Panis et al, 2022), endocrine disruptive chemicals (EDCs) from pharmaceutical waste such as antibiotics, anti-inflammatory, phenols, etc. (Ojha et al, 2021), organochlorine such as polychlorinated biphenyls (PCB) (Yasir et al, 2021), polychlorinated dibenzo-p-dioxins (PCDD), and dibenzofurans (PCDF) (Hashimoto et al, 2021).…”