Development of TiO2/Ti wire-mesh honeycomb for catalytic combustion of ethyl acetate in air

Wire-mesh sheets coated with Ti particles were developed by using an electrophoretic deposition (EPD) method. They were thermally treated at various working conditions for enhancing the coating strength. The Ti layer was suitably porous and showed a good adherence to the wire surface, due to partial sintering of Ti particles after thermal treatment at 900 °C. Then additional calcination at 600 °C resulted in the formation of a thin TiO2 layer (∼3 μm) on the outer surface of the Ti layer. After making Pt/TiO2/Ti-coated wire-mesh honeycombs (WMH) successfully, they were applied in catalytic combustion of ethyl acetate in air. The activity was much higher than that of a ceramic honeycomb containing a similar catalyst composition, especially in the high temperature ranges. This is explained by the difference in external mass transfer rate between the two modules. TiO2/Ti-WMH had several additional advantages: (i) the active catalyst platinum could be directly impregnated, since TiO2 could be used as a catalyst support. This reduces the manufacturing process with one-step, viz., support washcoating. (ii) Since there is no additional washcoat, it can be expected that the possibility of catalyst loss during the operation becomes very low. (iii) A rapid thermal response due to the small heat capacity.