Catalytic oxidation of 1,2-DCBz over V2O5/TiO2-CNTs catalysts: the effect of water

A series of vanadium oxide catalysts, supported on a titanium dioxide (TiO2)-carbon nanotubes (CNTs) carrier, was prepared. The purpose was to study the catalytic oxidation of 1, 2-dichlorobenzene (1,2-DCBz) during tests featuring a variable moisture content (0%-5% water) in the combustion air. The concentration of water vapour greatly influences the constitution of the catalytic surface and thus considerably affects the reactivity of V2O5/TiO2-CNT catalysts. A strong promoting effect was observed when feeding air with 1 vol. % of moisture, possibly owing to the formation of more active surface hydroxyl groups, an increased average oxidation state of vanadium (Vaos) and reduced carbon and chlorine accumulation on the catalytic surface. Addition of 5% moisture, however, evidently reduced reactivity, mainly owing to the competitive adsorption of water and 1,2-DCBz. The V2O5/TiO2-CNT catalysts were more obviously sensitive to humidity than the V2O5/TiO2 catalysts.