正庚烷在Ni_2P/SAPO-11催化剂上的加氢异构化反应性能

HYDROISOMERIZATION OF n-HEPTANE OVER Ni_2P/SAPO-11 CATALYST

采用次磷酸镍过量浸渍-分解法制备了Ni_2P/SAPO-11催化剂,通过低温N2吸附-脱附、XRD、HRTEM等分析手段对催化剂进行了表征。以正庚烷为原料,在固定床微反装置上考察了反应条件、Ni_2P负载量对正庚烷加氢异构化反应性能的影响,并与Pt/SAPO-11催化剂进行了对比。结果表明:Ni_2P/SAPO-11催化剂具有与Pt基催化剂相当的异构化选择性,但异构化活性和芳构化选择性较低;Ni最佳负载量(w)为4%,优化的反应条件为:反应温度400℃、压力0.5 MPa、氢烃体积比500、体积空速1h^(-1),在此条件下正庚烷的转化率为73.0%,异构化选择性为90%。

Ni2 P/SAPO-11 catalysts were prepared by decomposition of nickel hypophosphite impreg- nated on SAPO-11 support through excessive impregnation method and characterized by means of N2 sorption-desorption, XRD, HRTEM techniques. The effects of reaction conditions and nickel phosphide content on hydroisomerization of n-heptane were investigated in a fixed-bed reactor and compared with Pt/SAPO-11 catalyst. The results show that Ni2P supported on SAPO-11 molecular sieve has a high isomerization selectivity equivalent to the Pt-catalyst, however, the isomerization activity and aromatiza- tion selectivity were relatively lower. The optimum content of Niz P on SAPO-11 molecular sieve is 40%. At the optimal conditions： 400 ℃, 0.5 MPa, the volume ratio of H2 and n-heptane of 500, and LHSV of 1 h ^-1 , the conversion of n-heptane and the isomerization selectivity reaches 73.0 % and 90 %, respec- tively.