A novel diesel oxidation catalyst with low SO2 oxidation activity and capable of meeting Euro V emission standards

A diesel oxidation catalyst was prepared from several high performance materials: the new rare earth oxygen storage compound Ce0.75Zr0.25O2-Al2O3, the composite oxide Ti0.9Zr0.1O2 and chromium-modified ß molecular sieve. These component materials were characterized and used to prepare a Pt-based catalyst designed to reduce diesel engine exhaust emissions. The results of low temperature N2 adsorption-desorption and oxygen storage capacity tests demonstrated that Ce0.75Zr0.25O2-Al2O3 exhibits a large specific surface area and excellent oxygen storage capacity, and that Ti0.9Zr0.1O2 exhibits superior textural properties. Evaluations of catalytic activity showed that the catalyst prepared from these materials has reduced capacity for the oxidation of SO2 but high catalytic activity towards the oxidation of hydrocarbons (HC) and CO, and is also able to convert the exhaust soluble organic fraction at temperatures as low as 140 °C. Tests using a domestic YC4F-type diesel engine found that exhaust treated by the catalyst prepared in this research is capable of meeting the HC and CO emission requirements of the Euro V standard.

摘要制备了具有高性能的稀土储氧材料Ce0.75Zr0.25O2-Al2O3, 14;Ti0.9Zr0.1O2复合材料和Cr改性的β分子筛(Cr-β分子筛), 14;并以此制备了单Pt型柴油车尾气净化氧化型催化剂. 低温N2吸附-脱附、储氧量测试结果表明, 14;Ce0.75Zr0.25O2-Al2O3样品具有较大的比表面积和优异的储氧性能, 14;Ti0.9Zr0.1O2复合材料也具有优越的织构性能. 催化剂对HC和CO具有较高的催化活性, 14;可使SOF在140 °C开始转化, 14;且具有较低的SO2氧化活性. 在YC4F国Ⅳ柴油机的测试结果表明, 14;经该催化剂处理后的尾气排放能够满足欧Ⅴ排放标准对HC和CO排放要求.

A high performance diesel oxidation catalyst was prepared which demonstrated the ability to meet the Euro V standard for HC and CO exhaust emission content requirements.Figure optionsDownload as PowerPoint slide