Catalytic decomposition of methylene chloride by sulfated titania catalysts

Abstract

Catalytic decomposition of methylene chloride in air below 300°C was studied. Sulfated titania was very effective in converting 959 ppm methylene chloride selectively to CO, CO₂ and HCl. Complete decomposition of methylene chloride was achieved at low temperature (275°C). It was found that the acidic property of catalyst was a determinant factor for the catalytic activity. The presence of water vapor in the feed stream remarkably reduced the catalytic activity, which could be due to the blockage of acidic sites on the surface of catalyst by water molecules. A bifunctional catalyst comprising copper oxide was developed to improve the selectivity of catalytic oxidation, which indicated that copper oxide can promote the deep oxidation of methylene chloride. The crystal form of TiO₂ imposes an important influence upon the catalytic oxidation.

Keywords

catalytic decomposition / methylene chloride / sulfated titania

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