Low-cost catalysts for the control of indoor CO and PM emissions from solid fuel combustion

Cu–Mn based mixed oxide type low-cost catalysts have been prepared in supported form using mesoporous Al2O3, TiO2 and ZrO2 supports. These supports have been prepared by templating method using a natural biopolymer, chitosan. The synthesized catalysts have been characterized by XRD, BET-SA, SEM, O2–TPD and TG investigations. The catalytic activity for CO as well as PM oxidation was studied, in a view of their possible applications in the control of emissions from solid fuel combustion of rural cookstoves. The trend observed for the catalytic activity of the synthesized catalysts for CO oxidation was ZrO2 > TiO2 >Al2O3 while for PM oxidation it was observed to be TiO2 > ZrO2 >Al2O3. The effect of CO2, SO2 and H2O on CO oxidation activity was also investigated, and despite partial deactivation, the catalysts show good CO oxidation activity. An effective regeneration treatment was attempted by heating the partially deactivated catalysts in presence of oxygen. Redox properties of TiO2 and ZrO2 and their structure appeared to be responsible for their promotional activity for CO and PM oxidation reactions. These unordered mesoporous materials could be useful for such reactions where mass transfer is more important than shape and size selectivity