加氢异构化催化剂的研究——孔结构的影响

以无定型硅铝、十二元环分子筛ZIP 2和十元环分子筛ZIP 1为酸性组分制备了贵金属加氢异构化催化剂，并采用微反装置考察了其催化正癸烷异构化活性和异构产物选择性。结果表明，无定型硅铝由于酸性较弱且不具有规则孔道，因而制备的催化剂异构化催化活性和异构产物选择性较低。与分子筛ZIP 1相比，分子筛ZIP 2酸性较弱，但由其制备的催化剂的异构化催化活性更高，高约2%~5%。在低转化率下，由十二元环分子筛ZIP 2制备的催化剂具有更高的异构产物选择性和更高的多支链烃比例；随着转化率提高，由于多支链烃含量增加，且扩散阻力较大，因而裂化明显，由分子筛ZIP 1制备的催化剂反而具有更高的异构产物选择性， 90%转化率下的异构产物选择性提高约5%~7%。

Investigation on the hydroisomerization Catalyst:The Effect of the Pore Structure

Hydroisomerization catalysts containing noble metal were prepared by using amorphous silica alumina, ZIP 2 with a twelve membered ring pore and ZIP 1 with a ten membered ring pore as acidic components, respectively. The catalytic activities and isomer selectivities of them in decane hydroisomerization were investigated by using a flow microreactor. The results revealed that both the hydrosiomerization activity and isomerized product selectivity of the catalyst with amorphous silica alumina as acidic component were poor. In spite of the weaker acidity of ZIP 2 comparing to that of ZIP 1, the catalytic activity of the catalyst containing ZIP 2 was higher about 2%-5% due to its big pores. Also, at a low conversion, a higher isomer selectivity and higher content of multi branched isomers could be obtained over the catalyst containing ZIP 2. With the increase of conversion, hydrocracking was prominent due to the more content and strong diffusion resistance of multi branched isomers in the products over the catalyst containing ZIP 2, so the isomer selectivity over the catalyst containing ZIP 1 was higher than that over the catalyst containing ZIP 2, which was about 5% to 7% higher at the conversion of 90%.