Mn-Ce/AC催化剂低温NH_3选择性催化还原NO的性能

Performance of Mn-Ce/AC Catalyst for Low Temperature Selective Catalytic Reduction of NO with NH_3

采用浸渍法制备了一系列Mn-Ce/AC催化剂,以NH3为还原剂,通过程序升温反应考察其选择性催化还原NO的催化性能。结果表明,氨氮比和空速对Mn-Ce/AC催化剂的催化活性有一定的影响。n(NH3)∶n(NO)=1∶1,空速为2 000 h-1时活性最佳,在反应温度接近90℃时NO脱除率达到90%,在120～250℃温度范围内,能保持99%以上的高脱除率。Mn-Ce/AC催化剂抗水和抗硫性能良好,在相对较高的温度下,催化剂仍能保持高的脱硝性能;低浓度的SO2对催化剂脱硝性能影响不大,但当SO2浓度上升到1 500μL/L时,NO的最高脱除率只有70%。

Mn - Ce/AC catalyst was prepared by impregnation method and tested for selective catalytic reduction （SCR） of NO with ammonia through temperature programmed reaction（TPR）. Results indicted that both the n （NH3 ）/n （NO） ratio and space velocity have certain effect on the performance of Mn - Ce/AC catalyst. The NO conversion is up to 90% at 90 ℃ on Mn - Ce/AC when n （NH3 ）/n（NO） ratio is 11 and space velocity is 2 000 h-1, and a higher conversion of 99% is obtained during the reaction temperature of 120 - 250 ℃. Mn - Ce/AC catalyst shows good H2 0 resistance and SO/resistance, which can keep high activity when water vapor existed at higher temperature. With the increase of the SO concentration to 1 500 μl-/L, the NO conversion decreases significantly to 70%.