Investigation on the photocatalytic activity of TiO2@WO3/ZnO catalyst in the waste water treatment containing alkanolamine contaminants

Natural gas has wide range of acid gas concentrations such as CO2 and H2S. Alkanolamines dissolved in aqueous solutions are commonly employed to scrub CO2 and H2S from natural gas. As a result, the high level of this polutant is emitted through the waste water during cleaningIn this study a novel photocatalyst, TiO2@WO3/ZnO, has been designed and fabricated. To prepare the catalyst with the highest performance, the optimized weight fraction of WO3+Zno (with 1:4 weight ratio) has been alloyed with TiO2. The results from BET and BJH indicated that the synthesized catalyst had relatively high specific surface area (10.3 m^2 g^-1) and mesopore structure with cavities diameter of 10.9 nm. The as-synthesized photocatalyst has been employed in the alkanolamine contaminant degradation of wastewater obtained from an industrial gas refinery plant in the presence of LED light. In this regard, the degradation of alkanolamine during time was monitored using UV-Vis and fluorescence spectroscopies. The obtained results confirmed high performance of the designed catalyst in the rapid treatment of the wastewater of gas refinery effluent at very low catalyst loading of only 0.5 wt.%, thereby making it a good candidate for the catalytic purposes. Finally, a possible mechanism for catalytic degradation of alkanolamine over TiO2@WO3/ZnO was suggested.