Monolithic catalysts for the combustion of dichloromethane: effect of coating method, catalyst support, and additives

Supported Pt catalysts were considered to have excellent activity and stability in the catalytic combustion of chlorinated VOCs, which, however, face challenges on the transformation to pilot application. Herein, we prepared a series of Pt catalysts and coated them on honeycomb cordierites uniformly to prepared monolithic catalysts. The effects of different coating methods (washcoating, one-pot synthesis, or impregnation), supports (TiO2 or HZSM-5) and additives (Co3O4 or CeO2) on the catalytic performance were investigated. The advantage of the washcoating method is that the active phase of catalysts worked as a unit, which means a stronger interaction between them. In this research, the Pt-Co/HZSM-5 prepared by the washcoating method exhibited the best activity in the catalytic oxidation of dichloromethane (T50=260 ºC and T90=335 ºC) and showed stability for at least 48 hours (at 90% conversion). Such an excellent performance was attributed to the abundant Oads species and high BET surface area.