Catalytic oxidation for air pollution control

Bench-scale experiments have been conducted to evaluate a series of titania-supported Pr-Pd (as oxides) catalysts in the presence and absence of MoO3 and Fr2O3 additives for their effectiveness in the complete catalytic oxidation of volatile organic compounds (VOCs) in air likely to be found in waste gases. Under oxidizing conditions, all of the catalysts promoted the complete oxidation of VOCs to CO2 and H2O. 99 % Conversion was achieved with a C2H4-C2H6 gas mixture in air at temperatures between about 160-450 degrees C and at a space velocity of 20,000 h(-1). Oxidation activity for the titania supported catalysts were found to decrease in the order Pt-Pd-Mo-Fe > Pt-Pd-Mo > Pt-Pd-Fe > Pr-Pd. However, the addition of MoO3 and Fe2O3 increase the catalyst activity and reduce the reaction temperature for the complete destruction. Ageing was also performed in order to study the stability of the most active catalyst. Pr-Pd-Mo-Fe (as oxides) on titania catalyst is effective in oxidizing a wide range of volatile organic compounds al relatively low temperatures (220-405 degrees C) and and at a space velocity of 40,000 h(-1) and is resistant to poisoning by halogenated and amine volatile organic compounds.