载镍硅磷酸铝分子筛的催化活性研究

用浸渍法制备了Ni/SAPO-5分子筛、Ni/AlPO_4-5分子筛、Ni/AlPO_4胶体3种催化剂,用催化色谱法研究了它们对正己烷裂化的催化活性和产物分布,并进行了IR、EPR、XRD分析。结果表明:B酸、Ni°都是裂化反应的活性中心,在Ni/SAOP-5(R)上既有氢解活性中心,也有异构化活性中心;催化活性随还原流量的增大而增大,低还原温度可得到较高的裂化活性。

CATALYTIC ACTIVITY STUDY OF NICKEL LOADED SILICOALUMINOPHOSPHATES

Ni/SAPO-5,Ni/AIPO_4-5 and Ni/AIPO_4 gel catalysts were prepared by the impregnation method,and characterized by IR,EPR,XRD.Their catalytic activity and selectivity for n-hexane cracking were determined by catalytic chromatog- raphy.The results showed that both Bronsted acid site and Ni were the active center responsible for cracking reaction. There are not only hydrogenolysis active centre but also isomerization active centre on Ni/SAPO-5(R).The catalytic ac- tivity is much higher when the higher flow rate of reductant(H_2)and lower reducting temperature were adopted.