低贵金属Pt-Rh型三效催化剂空燃比性能的研究  

Study of Air/Fuel Ratio Performance of Low-Precious Metal Pt-Rh Three-Way Catalysts

作　　者：郭家秀[1] 袁书华[1] 龚茂初[1] 张磊[1] 张丽娟[1] 赵明[1] 陈耀强[1] 

机构地区：[1]四川大学化学学院,成都610064

出　　处：《化学学报》2007年第10期937-942,共6页Acta Chimica Sinica

基　　金：国家自然科学重点基金(No.20333030);国家自然科学基金(No.20273043)资助项目.

摘　　要：研究了以浸渍法制备的低贵金属Pt-Rh型三效催化剂对C3H8,CO,NO的催化活性.主要考察了CeO2-ZrO2和BaO的添加对催化剂空燃比性能的影响,通过氧化反应、水气变换和蒸汽重整的性能研究,探讨了催化剂三效工作窗口扩大的原因.结果表明,催化剂中只添加CeO2-ZrO2时即具有优异的水气变换性能,蒸汽重整在250℃左右发生,并且在450℃以下时C3H8的转化率一直保持在20%左右;BaO添加到含有CeO2-ZrO2的催化剂中对水气变换和蒸汽重整则有明显的促进作用,能进一步扩大催化剂的三效工作窗口;催化剂中只添加CeO2-ZrO2时,能明显提高催化剂对CO的氧化反应活性,但对C3H8的氧化反应的影响则不明显;BaO和CeO2-ZrO2同时存在于催化剂中时,能进一步提高CO的氧化反应活性,对C3H8的氧化反应则没有明显的促进作用.The catalytic activities on C3H8, CO and NO of low-precious metal of Pt-Rh three-way catalysts prepared by impregnation were studied. The influence of adding CeO2-ZrO2 and BaO into catalysts on air-to-fuel ratio （A/F） was mainly investigated. The reason that A/F was broadened was studied by oxidization reaction, water-gas shift and steam reforming over catalysts. The results indicated that the catalyst merely containing CeO2-ZrO2 had excellent ability of water-gas shift, and steam reforming of C3H8 began to occur at 250 ℃ and maintained 20% of the conversion of C3H8 before 450 ℃. BaO was added to the catalyst containing CeO2-ZrO2, which could significantly promote water-gas shift and steam reforming and further broadened the three-way working-window of the catalyst. Only addition of CeO2-ZrO2 to the catalysts could promote oxidation reaction activity of CO, but the influence on oxidation of C3H8 was not obvious. Catalyst containing BaO and CeO2-ZrO2 could further promote oxidation reaction activity of CO but did not obviously promote oxidation of C3H8.

关 键 词：Pt-Rh 三效催化剂 水气变换 蒸汽重整 

分 类 号：O643.36[理学—物理化学]