正庚烷在β沸石负载碳化钼催化剂上的异构化研究

Study on n-heptane isomerization on β zeolite supported molybdenum carbide catalyst

利用程序升温还原法制备了β沸石负载碳化钼催化剂。XRD表征显示,利用正戊烷作为碳源得到了对异构化具有活性的β-Mo2C。以正庚烷为模型反应物,在连续流动固定床反应装置上考察了温度、压力、空速和氢烃比对β-Mo2C/β沸石催化剂临氢异构化反应性能的影响。获得了β沸石负载碳化钼催化剂上正庚烷异构化的最佳反应条件温度270℃-275℃,压力1.0MPa-1.5MPa,体积空速1.0h-1,氢烃体积比200∶1。在最佳条件下反应物转化率为82%,选择性和异构产物收率分别达到71%和58%。

β Zeolite supported molybdenum carbide catalyst has been prepared by temperature- programmed reduction with n-pentane as a source of carburization, and characterized by XRD. The influences of reaction temperature, pressure, space velocity and the ratio of hydrogen to hydrocarbon on the catalytic performance for hydroisomerization over β-Mo2C/β zelite have been investigated in a fixed-bed down-flow reactor using n-heptane as a model reactant. The optimum conditions for the isomerization of n-heptane were 270 ℃～ 275 ℃, 1.0 MPa - 1.5 MPa, LHSV 1.0 h^-1 and the hydrogen to hydrocarbon ratio （Volume Ratio） 200： 1. The results of the reaction showed that the selectivity and yield of isomers reached to 71% and 58%, respectively, with the n-heptane conversion of 82% in the optimum conditions.