Pt/SAPO-11临氢异构化催化剂反应特性的研究

Characteristics and process parameters for hydroisomerization over Pt/SAPO-11 catalyst

以正庚烷为模型化合物,在10mL连续流动固定床反应装置上,考察了温度、压力、空速与氢烃摩尔比对0.4%Pt/SAPO-11催化剂临氢异构化反应性能的影响。结果表明,催化反应以烷烃异构化为主,正庚烷转化率达70%时异构产物选择性保持在90%以上,压力和氢烃摩尔比较小时,产物的选择性较高;压力太高裂解产物生成量增多对异构化选择性不利。获得了正庚烷在Pt/SAPO-11催化剂上临氢异构化的优化反应条件为,360℃～380℃,0.5MPa～1.0MPa,2.1h1～4.1h1,H2/CH(摩尔比)2～6;烷烃临氢异构化反应的一个条件变化,需要其他条件的改变来达到最佳的匹配。

A catalyst for hydroisomerization with high isomerization selectivity and excellent stability has been obtained. For the advanced use of the catalyst in industry, the effects of reaction parameters such as temperature, pressure, space velocity and hydrogen to hydrocarbon H2/CH (mol ratio) on the catalytic performance of 0.4% Pt/SAPO-11 hydroisomerization catalyst have been investigated in a 10 mL fixed-bed down-flow reactor using n-heptane as a probe molecule. The catalytic behavior and the optimum reaction parameters have been thus obtained. The evaluation results manifest that the main reaction of n-heptane over Pt/SAPO-11 is isomerization, and the selectivity to i-C7 maintains above 90% even at the conversion up to 70%. The optimum reaction conditions are: temperature 360°C-380°C, pressure 0.5 MPa-1.0 MPa, WHSV 2.1 h-1-4.1 h-1, and H2/CH (mol ratio) 2-6. Moreover, the conclusion can be drawn from the obtained data that the reaction parameters interact with each other, indicating that variation of one parameter needs the adjusting others in order to gain an optimal performance.