富氧条件下Ag/Al2O3-Cu/Al2O3组合催化剂催化乙醇选择性还原NOx

 在富氧条件下,以乙醇为还原剂,考察了不同金属负载量的Ag/Al2O3和Cu/Al2O3催化剂选择性还原NOx的活性. 结果表明,4%Ag/Al2O3和10%Cu/Al2O3分别为各自体系中的最佳催化剂. 4%Ag/Al2O3具有很高的选择性催化还原NOx的活性,但同时会产生一定量的副产物CO. 10%Cu/Al2O3选择性催化还原NOx的活性不高,但却具有很好的消除CO的活性. 将4%Ag/Al2O3和10%Cu/Al2O3以不同方式组合,其评价结果表明,4%Ag/Al2O3-10%Cu/Al2O3组合催化剂具有与单纯4%Ag/Al2O3相似的NOx脱除活性,同时能够完全消除反应过程中产生的CO,并且能大大降低尾气中乙醇和乙醛的浓度.

Selective Catalytic Reduction of NOx by Ethanol over Combined Catalyst Ag/Al2O3-Cu/Al2O3 in Excess Oxygen

The selective catalytic reduction of NOx by ethanol was studied over Ag/Al2O3 and Cu/Al2O3 catalysts with different metal loadings. The 4 % Ag/Al2O3 and 10 % Cu/Al2O3 showed the highest NOx reduction activity, respectively. The 4 % Ag/Al2O3 catalyst showed excellent NOx to N2 activity but produced a large amount of CO during the reduction process. The 10 % Cu/Al2O3 catalyst was not so active in the reduction of NOx by ethanol, but it was very effective for removing the CO. The combined catalyst formed by direct placing 10 % Cu/Al2O3 after 4 % Ag/Al2O3 showed a similar activity for the NOx reduction and could also remove the CO efficiently. In addition, the concentration of ethanol and aldehyde was also greatly reduced in the effluent gas.