天然气车尾气净化催化剂研究进展

A review of natural gas vehicles de-pollution catalysts

本文综述了天然气车(NGV)尾气净化催化剂的反应原理及催化材料的作用。总结概括了减少贵金属用量、提高甲烷(CH4)的低温氧化活性、增强对水(H2O)和二氧化硫(SO2)的抗中毒性能、扩大空燃比窗口等NGV尾气净化催化剂的关键技术问题。目前的实验结果已证明稀土材料的应用可以显著减少贵金属的用量,提高CH4氧化的低温活性并拓宽催化剂空燃比窗口。介绍了国五稀燃NGV氧化催化剂和国六当量比NGV三效催化剂的应用情况。中国新型NGV尾气净化催化剂已实现大规模商业化。为了工业的健康与可持续发展以及应对不断升级加严的排放法规,未来仍需要不断降低贵金属用量,提高催化剂的低温活性以及提高催化剂的选择性。为了解决上述问题,开发稀土或过渡金属改性的新型功能催化材料是势在必行的。

The reaction principles of natural gas vehicles(NGV)de-pollution catalysts and the roles of catalytic materials were summarized.The key technical issues of NGV de-pollution catalysts were introduced,including reducing the amount of precious metals,improving the low-temperature activity of CH4 oxidation,strengthening the anti-poisoning performance of H2O and SO2,and widening the window of the air/fuel ratio.The current experimental results had verified that the application of rare earth materials can significantly reduce the amount of precious metals,improve the low-temperature activity of CH4 oxidation,and widen the window of the air/fuel ratio.The applications of China V lean-burn natural gas vehicle oxidation catalysts and China VI stoichiometric air/fuel ratio natural gas vehicle three-way catalysts were introduced.China VI NGV de-pollution catalysts have been commercialized on a large scale.For the healthy and sustainable development of the industry,it is necessary to continuously reduce the amount of precious metals,increase the low-temperature activity and improve the selectivity of the catalyst in the future.To address the above issues,it is necessary to develop novel functionalized catalytic materials modified by rare earths or transition metals.