Efficient photocatalytic degradation of organics present in gas and liquid phases using Pt-TiO2/Zeolite (H-ZSM). (June 2016) - Neppolian, B.
Abstract: TiO2 -encapsulated H-ZSM photocatalysts were prepared by physical mixing of TiO2 and zeolites. Pt was immobilized on the surface of the TiO2 -encapsulated zeolite (H-ZSM) catalysts by a simple photochemical reduction method. Different weight ratios of both TiO2 and Pt were hybridized with H-ZSM and the catalytic performance of the prepared catalysts was investigated for 2-propanol oxidation in liquid phase and acetaldehyde in gas phase reaction. Around 5–10 wt% TiO2 -encapsulated H-ZSM catalysts was found to be optimal amount for the effective oxidation of the organics. Prior to light irradiation, Pt-TiO2 -H-ZSM showed considerable amount of catalytic degradation of 2-propanol in the dark, forming acetone as an intermediate. In this study, Pt has played a major and important role on the total oxidation of 2-propanol as well as acetaldehyde. As a result, no residual organics were present in the pores of the zeolites. The catalysts could be reused more than three times without losing their catalytic activity in both phases. The Pt-TiO2 -H-ZSM photocatalysts could overcome the problem of strong adsorption of organics in the zeolite pores (after the reaction). Thus, Pt-TiO2 -H-ZSM can be used as a potential catalyst for both liquid and gas phase oxidation of organic pollutants. Graphical abstract: Highlights: Total catalytic oxidation of organics present in liquid and gas phases within a short period of time. Dark reaction takes place with Pt-TiO2 -H-ZSM. No residual organics present in the pores of zeolites. Overcome the problems of strong adsorption of organics (unreacted) in the pores of zeolites and make the catalysts active for consecutive runs. Pt-TiO2 -H-ZSM is the best catalyst for liquid phase oxidation.