Activity enhancement of acetate precursor prepared on MnOx-CeO2 catalyst for low-temperature NH3-SCR: Effect of gaseous acetone addition

MnOx-CeO2catalysts are developed by hydrolysis driving redox method using acetate precursor(3 Mn1 Ce-Ac) and nitrate precursor(3 Mn1 Ce-N) for the selective catalytic reduction(SCR) of NOxby NH3.A counterpart sample(Cop-3 Mn1 Ce) was prepared by the NH3·H2O co-precipitation method for comparison purpose.Combining the results of physicochemical properties characterization and performance test,we find that the 3 Mn1 Ce-Ac catalyst with some nanorod structures is highly active for the deNOx process.The SCR activity of the 3 Mn1 Ce-Ac catalyst is more admirable than the 3 Mn1 Ce-N and the Cop-3 Mn1 Ce catalysts due to plentiful Lewis acid sites,excellent low-temperature reducibility,and superior surface area resulted from O2generation during the pre paration procedure.The 3 Mn1 Ce-Ac still exhibits the greatest performance for the deNOx process when gaseous acetone is in the SCR feed gas.The NOxconversion and N2selectivity over the 3 Mn1 Ce-Ac are both improved by gaseous acetone above150℃ due to the inhibition of SCR undesired side reactions(NSCR & C-O reactions) and "slow-SCR" process.