新型碳八芳烃异构化催化剂的制备及其性能

Preparation and catalytic performance of a novel catalyst for C_8 aromatics isomerization

选用独特结构的分子筛材料为酸性组元,制备了新型碳八(C8)芳烃异构化催化剂,并对该催化剂的异构化能力进行了研究。选取目前工业用催化剂作为对比催化剂,采用相同的反应原料,在各自最佳的反应条件下,与新型催化剂进行比较。实验结果表明,随着原料的不同,在反应产物中,新型催化剂反应中的对二甲苯在二甲苯中的浓度为19.06%～24.14%,乙苯转化率为32.07%～41.50%,C8烃收率为97.08%～99.11%,远高于对比催化剂;同时,甲苯含量为0.26%～1.20%,重芳烃含量为0.22%～0.62%,远低于对比催化剂。同对比催化剂相比,新型催化剂具有较高的异构化活性和选择性,能在较高的空速下运行。

A novel C8 aromatics isomerization catalyst was prepared using a special structured zeolite as the acid component, its catalytic activity and selectivity for xylene isomerization was studied. A commercial catalyst used currently was selected as a contrast catalyst for the evaluation under each preferable reaction conditions respectively. With different stuff, the PX value in the xylene products obtained over the novel catalyst was 19.06%--24.14%, the ethylbenzene conversion was 32.07%-- 41.50%, the Cs hydrocarbon yield was 97.08%--99.11%. These results were all substantially higher than those obtained over the contrast catalyst. Meanwhile, the toluene value of the novel catalyst was 0.26%-- 1.20%, C9 or heavier aromatics value was 0.22%--0.62%, they were both much lower than those of the contrast catalyst. Thus, the prepared novel catalyst has better catalytic activity and selectivity for C8 aromatics isomerization, and it can be operated under higher WHSV （weight hourly space velocity）.