【作者】 李治国；

【导师】 郭锡坤；

【作者基本信息】 汕头大学 ， 工业催化， 2006， 硕士

【摘要】 氮氧化物是目前主要的大气污染物，它所引起的酸雨和光化学烟雾等危害已经引起人们高度重视。贫燃发动机具有经济性和节能环保的优点，传统的三效催化剂在贫燃条件下不能有效的消除氮氧化物，研究和开发适合贫燃条件的汽车尾气的净化催化剂，是当前催化研究领域的热点课题。 本研究以有良好催化活性的HZSM-5分子筛为载体，用硫酸对其进行处理，通过浸渍法负载上活性组分铜，制得Cu/HZSM-5（AT）催化剂；并对制得的Cu/HZSM-5（AT）催化剂添加稀土组分，考察了酸处理载体和添加的稀土组分对催化剂催化活性的影响。研究了催化剂的制备工艺，并通过XRD、TG、IR、NH₃-TPD、Py-IR、FT-IR和H₂-TPR等分析手段对催化剂的结构和性能进行了研究。研究结果表明： （1） 用同样的方法制得的不同类型的分子筛、不同硅铝比分子筛催化剂的活性测试结果表明，氢型的分子筛制得的催化剂的活性明显好于钠型分子筛制得的催化剂，分子筛的硅铝比对催化剂的活性有重要影响。 （2） 用硫酸处理过的HZSM-5分子筛经过焙烧，不仅使总的酸量增加，而且生成了具有超强酸结构的强酸中心。活性测试的结果表明，经过酸处理的载体制得的催化剂的选择性还原NO的转化率和活性温度窗口都有了大幅提高。 （3） 研制的高负载量的催化剂，具有良好的稳定性和一定的抗水蒸气的能力，在所制得的催化剂上添加稀土镧和铈不能进一步改善催化剂的催化活性。更多还原

【Abstract】 Nitric oxide is the major polluter of the air pollution. People have given much attention on the acid rain and chemical smog which was formed by it. Lean-burn engine has the property of energy saving and enviromental protection, while the traditional three-way catalyst can’t remove the nitric oxide effectively under lean-burn conditions. Thus to develop a kind of new catalyst which is suitable for the exhausted gas expelled by the lean-burn engine is becoming popularly in the catalytic field.In this thesis, we focused on the support of HZSM-5 zeolite which had better catalytic activity and treated the zeolite with sulfur acid. Then we loaded Cu by impregnation method. The Cu/HZSM-5 （AT） catalyst was prepared. We added rare earth on the Cu/HZSM-5 （AT） catalyst. The effect of acid treatment and rare earth on catalytic performance was investigated. The influences of preparation was also studied and the structure of catalysts have been investigated by XRD、TG、IR、 NH₃-TPD、 Py-IR、FT-IR and H₂-TPR and so on. The results are as follows:（1） Catalysts were prepared by the same method by using different kind of zeolites and different ratio silicon to aluminum zeolites. The results showed that the catalysts made by hydrogen type zeolite had better catalytic performance and the ratio of silicon to aluminum played an important role in catalytic performance.（2） The calcination of HZSM-5 zeolite treated by sulfur acid not only could improve its acid quantity, but also increased strong acid sites with structure of super acid. Results showed that the process of acid treatment increased the conversion of NO and made the catalyst active in wider temperature range.（3） The Cu/HZSM-5（AT） catalyst had high copper loading in this thesis. It showed good stability and better capability of resistance against the water vapour. The addition of rare earth La and Ce on Cu/HZSM-5 （AT） catalyst couldn’t improve the catalytic performance.更多还原