改性贵金属催化剂催化还原脱除NO

含有NO的工业废气直接排放会严重污染空气,须对含有NO的工业废气进行净化处理.采用NH3为还原剂贵金属铂催化剂进行了低温还原NO脱除烟气中氮氧化物性能的研究.结果表明:实验室制备的贵金属铂催化剂具有高的低温活性和选择性催化还原脱除NO的性能,但该催化剂易被原料气中少量的硫化物(SO₂)中毒而影响其稳定性;用稀土元素La和Ce对贵金属铂催化剂进行改性,改性后贵金属铂催化剂的稳定性得到了大幅度提高,出口气体中氮氧化物浓度大幅度降低.本实验Pt∶La∶Ce最佳摩尔比为1∶3.78∶3.56.

Catalytic Removal of NO on Modified Precious Catalyst

The streams of waste gases containing NO from industries would cause seriously pollution on the environment if they are directly discharged without further purification, which must be treated in view of environmental protection. The property of removal of NO from the waste gas at lower temperature performed on platinum catalyst by reduction with NH₃ was investigated in this study. Experimental study showed that the precious catalyst, platinum, had good activity at low temperature and high selectivity of catalytic removal of NO from the waste gas by ammonia. However, its performance was affected by the sulfur compound, SO₂, which was present in the waste gas. Results indicated that the performance of platinum supported catalyst could be improved with addition of lanthanides on it. The suitable compositions of the modified catalyst were 1: 3.78: 3.56 molar ratio of Pt: La: Ce in the experiment.