Effect of Preparation Condition on NO Removal Activity over Activated Carbon Honeycomb Supported MnOx Catalyst

MnOx/ACH catalyst, manganese oxides supported on an activated carbon honeycomb (ACH) using phenolic resin as adhesive, was used for selective catalytic reduction of NO with NH3 at low temperature. The effect of preparation conditions on the activity of NO removal was investigated. The results showed that, with the increasing of mass fraction of phendic resin, the mechanical strength of the ACH increased, while the micropore surface area and micropore volume decreased. With the increasing of mass fraction of phenolic resin in ACH, NO removal activity over MnOx/ACH decreased gradually. NO conversion increased with increasing Mn loading(mass fraction of Mn) from 3% to 15%, while further increase led to less change in NO removal activity. In the temperature range of 300—600 °C, NO conversion showed a maximum. Additionally, the preoxidation of MnOx/ACH in air significantly enhanced the activity of NO removal, because the low valence state of manganese oxide was transformed into high valence one. Under the optimal preparation conditions of 25% mass fraction of phenolic resin, 10% Mn loading, the calcination temperature of 400 °C and preoxidized by air, about 95% NO conversion can be obtained over the MnOx/ACH catalyst at 200 °C.