High efficiency CuOx/TiO2-ZrO2 for chlorobenzenes catalytic oxidation via adjusting surface acidic sites

A series of CuOx/TiO2-ZrO2 (Cu/TZ) catalysts were prepared and applied in catalytic elimination chlorobenzene. Cu/TZ exhibited a 90% CB conversion at a relatively lowest temperature (249 degrees C), following by a lower activation energy (27.1 kJ/mol) and a higher reaction rate (11.5 x 10-7 mmol s-1 gcat-1 at 260 degrees C) in comparison with Cu/T and Cu/Z. Systematically surface properties and structural analysis indicated that the superior performance over Cu/TZ could mainly result from its well-dispersed CuOx active species, the abundant surface adsorbed oxygen, and the plentiful surface acid density (102.5 & mu;mol/gcat), especially the Lewis acid sites. Detailed in in situ DRIFTS results further demonstrated the smooth adsorption of CB on those Lewis acid sites over Cu/TZ, which in turn facilitated subsequent C-Cl bond breaking and the catalytic oxidation of the nucleophilic oxygen, thus contributing to its superior catalytic performance. This study could help to guide the development of efficient catalysts for enhancing CB oxidation activity.

Automated summary

A series of CuOx/TiO2-ZrO2 (Cu/TZ) catalysts were prepared and applied in catalytic elimination of chlorobenzene. Cu/TZ exhibited superior catalytic performance with 90% conversion at a relatively low temperature, lower activation energy and higher reaction rate compared to Cu/T and Cu/Z. The superior performance of Cu/TZ was attributed to its well-dispersed CuOx active species, abundant surface adsorbed oxygen, and plentiful surface acid density, particularly the Lewis acid sites.