Photocatalytic degradation of Methyl Orange by Tungstophosphoric Acid Impregnated in Zeolites NH_4 ZSM5

Abstract

Photocatalytic degradation mediated semiconductor materials is a successful and convenient alternative for the treatment of wastewater containing organic contaminants. The heteropolyacids with Keggin structure, like tungstophosphoric acid (TPA), present photocatalytic characteristics similar to photocatalysts. However, they present low surface area, and high solubility in water and organic solvents. To overcome this drawback, they are deposited on high surface area solids, such as zeolites.
The incorporation of TPA was performed by wet impregnation onto NH_4ZSM5 zeolites, synthesized by the hydrothermal method. The resulting materials were characterized by different techniques and were evaluated in the photodegradation of azodic type dye, methyl orange (MO). The effects of the amount of catalyst, the amount of TPA deposited on the matrix, the addition of H2O2and the pH of the solution were evaluated. Photoactivity was compared with the salt (NH_4)_3[PW_12O_40
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