催化裂化反应中支链烷烃生成途径的分析

ANALYSIS OF REACTION ROUTES TO FORM BRANCHED ALKANE ISOMERS IN CATALYTIC CRACKING

分析了大庆VGO原料在酸性分子筛催化剂上反应时汽油烷烃异构体的产生及转化。烷烃异构体主要是甲基异构体,在反应产物中的量随反应深度增加而增加,表明骨架异构反应主要通过质子化环丙烷中间体(PCP)进行。甲基异构体中主要是单甲基异构体,其次是二甲基异构体,三甲基异构体的比例极少。长支链烷烃主要是通过较大的质子化环烷烃中间体如PCB、PCPe、PCH等生成,而多甲基烷烃则是由单甲基烷烃进一步通过质子化环丙烷中间体生成。

Formation and Daqing.VGO＇s cracking transformation of the branched alkanes in naphtha were analyzed during on acid catalysts. The yields of branched alkanes in reaction product increased with the conversion. The branched alkanes mainly consisted of methyl alkanes, which suggested that skeletal isomerization proceeded through substituted protonated cyclopropane intermediates （PCP）. Methyl alkanes consisted mainly of monomethyl alkanes, then of dimethyl alkanes, and of a little trimethyl alkanes. The long-chain branched isomers were formed mainly via intermediates such as PCB, PCPe, PCH rather than via PCP, while the multi-methyl alkanes was formed from monomethyl alkanes via PCP.