摘要
采用浸渍法制备了MoO_3/ZrO_2,用低温氮吸附-脱附法和NH_3-程序升温脱附法(TPD)分别对其比表面积和酸碱性进行了表征.结果表明,MoO_3/ZrO_2具有106.8m^2/g的比表面积和超强酸的性能.用等体积浸渍法制备了Pt/MoO_3/ZrO_2催化剂,在汽车尾气模拟气中考察了其对C_3H_8、CO和NO的催化活性.与传统三效催化剂Pt/La_2O_3/Al_2O_3相比较,Pt/MoO_3/ZrO_2具有更好的低温起燃性能和更宽的空燃比窗口,并显著地改善了C_3H_8在富氧状态下的转化效率.通过XRD、H_2-TPR对催化剂进行了表征,结果表明,Pt在催化剂载体上具有高度的分散性和优异的氧化还原性能.
MoO3/ZrO2 was prepared by impregnation method.Its specific surface area,pore size, pore volume and surface acidity were investigated by means of low temperature nitrogen adsorption- desorption and NH3-temperature programmed desorption.By using MoO3/ZrO2 and La2O3/Al2O3 as catalyst support,Pt/MoO3/ZrO2 and Pt/La2O3/Al2O3 catalysts were prepared by wet impregnation method and the activity test of C3H8,CO,NO were also investigated in the simulated automotive gas. The results show that MoO3/ZrO2 has good texture（S（BET）=106.8m2/g）and surface super-acidity.And the catalysts were also characterized by X-ray diffraction and H2-temperature programmed reduction. Compared with traditional three-way catalyst Pt/La2O3/Al2O3,Pt/MoO3/ZrO2 exhibits lower light-off temperature of hydrocarbon（230℃）,carbon monoxide（200℃）,and nitrogen oxides（210℃）and wider operational air-to-fuel ratio window,which especially improves C3H8 conversion under higher oxidative conditions.The results also show that Pt on the catalyst support has high dispersion and excellent redox properties.
出处
《无机材料学报》
SCIE
EI
CAS
CSCD
北大核心
2008年第6期1267-1271,共5页
Journal of Inorganic Materials
基金
国家自然科学重点基金(20333030)
国家“863”项目(2006AA06z347)
