摘要随着国民经济的不断发展，汽车的数量在不断地增加，随之而来的就是更多的汽车尾气的排放，汽车尾气也成为了大气的主要污染源之一。汽车尾气主要包含一氧化碳、碳氢化合物和氮氧化物。他们不仅危害了人们身体的健康，也加重了环境的恶化，成为了各国都无法忽视的问题。钙钛矿型复合氧化物具有热稳定性能好和价态可调控等优点，在汽车尾气净化处理方面的应用一直备受关注。本文选取钙钛矿型复合氧化物催化剂作为研究对象，用溶胶凝胶法结合自燃法制备一系列稀土钙钛矿结构催化剂，在连续流动的体系上测定了催化剂的CO氧化活性。优化葡萄糖溶胶凝胶法，以乙醇为溶剂，PEG为分散剂，结合自燃法合成具有分散性较好，成相温度低的钙钛矿结钩的稀土催化剂，并以CO氧化反应为目标反应，研究组成，结构，形貌及催化性能的之间的关系；结果表明，LaNiO3的催化活性较差，CO完全转化温度T100为300 oC，随着B位Co3+ 的加入，其催化活性不断提高，当全部为LaCoO3时，其T100为180 oC，说明LaCoO3的催化活性优于LaNiO3。同时考察了A位离子Cu2+的掺杂，以及负载CuO或者Pd其催化活性的变化，结果表明A位离子的掺杂对其活性影响不是太大，稍微有一定的改善，但是负载CuO，其影响较大，催化活性有较大的提高。但是非常遗憾的是，Pd的负载对LaCoO3的CO氧化活性的性能改善。22495
毕业论文关键词：稀土； 钙钛矿结钩； CO催化氧化；溶胶凝胶法自燃法；负载型Pd催化剂
Abstract
With the continuous development of the national economy, the number of cars is constantly increasing, and was followed by more vehicle exhaust emissions, vehicle exhaust has become one of the major sources of pollution of the atmosphere. Automobile exhaust consists mainly of carbon monoxide, hydrocarbons and nitrogen oxides. They not only endanger the physical health of people, but also aggravated the deterioration of the environment, which has become the countries are not ignored. Perovskite- type oxides have good thermal stability and valence states can regulate, etc., used in automobile exhaust purification processing has been of concern. In this paper, we selected perovskite-type composite oxide catalyst for the study and combined with the sol-gel method spontaneous combustion to prepare a series of rare earth perovskite catalysts. The catalysts have been characterized by XRD, SEM, H2 – TPR, respectively. The results show that all the samples present perovskite structure with well – dispersed morphology. Among these LaCoxNi1-xO3 samples, the CO oxidation activity of LaNiO3 shows the lowest. And with the increase of the Co amount, the activity is increasing. When x reaches 1, LaCoO3 present the best activity. Furthermore, we loaded CuO or Pd in the perovskite catalysts and found that the loading of CuO can obviously improve the activity; however, Pd – loaded LaCoO3 can not show the better activity for the CO oxidation.
Keywords: perovskite; rare earth; CO oxidation; sol-gel combined with combustion method; Pd – loaded catalyst
目录
第一章 绪论    2
1.1前沿    2
1.2国内外研究现状    3
1.2.1汽车尾气的产生机理及危害    3
1.2.2汽车尾气排放控制技术    3
1.2.3汽车尾气净化催化剂研究进展    4
1.2.4钙钛矿型复合氧化物晶体结构特点    4
1.2.5 钙钛矿型复合氧化物优点    5
1.2.6钙钛矿型复合氧化物催化剂的制备    5
1.2.7 贵金属催化剂的介绍    8
1.2.8影响催化剂催化性能的因素    8
1.3课题研究的目的与意义    10
1.3.1课题研究的目的    10 应用于CO氧化反应中的稀土钙钛矿结构催化剂的制备及其性能研究:http://www.youerw.com/huaxue/lunwen_15158.html