MnOx/TiO2低温脱硝催化剂优选及其性能分析

摘要

Under the simulated emission conditions of certain stationary source,two kinds of unsupported and one supported MnOx catalysts were prepared and their performances on low-temperature de-NOx were compared respectively.One catalyst named α-MnO2/TiO2 with high catalytic activity in low temperature was filtered out first,and then,the performance of the catalyst in the presence of H2O and SO2 was measured.The results show that in the environment with no H2O or SO2,the unsupported catalysts MnOx and the supported catalysts MnOx/TiO2 all have high reactivity at temperatures between 150 ℃ and 200 ℃ with the NOx conversion rate close to 100％.However,the performance of the MnOx/TiO2 catalysts deteriorates in the presence of H2O or SO2; especially when H2O and SO2 are added together,the catalytic activity drops to 22％.Therefore,there are still many limitations to the popularization of the low-temperature de-NOx technology.Further studies are needed onthe resistance to H2O and SO2 in low-temperature selective catalytic reduction (SCR).%在模拟固定源烟气排放特征的环境下,分别研制比较了2种非负载型和1种负载型锰基催化剂的低温脱硝性能,初步筛选出低温活性较高的催化剂α-MnO2/TiO2,并对其抗水蒸气(H2O)和抗SO2性能进行了研究.试验结果表明,在无H2O和无SO2环境中,温度为150～200℃时,非负载型催化剂MnOx和负载型催化剂MnOx/TiO2的催化活性均较高,NOx转化率接近100％;但MnOx/TiO2催化剂低温时对H2O与SO2的耐受性差,特别是SO2和H2O同时加入时,催化活性将降至22％.低温脱硝工艺的工业化推广还存在诸多局限性,需进一步研究低温脱硝催化剂的抗H2O和抗SO2性能.