热裂化和流化催化裂化装置生产的C4、C5馏分含30％～80％的烯烃，日本山阳石化公司用这些价值低的烯烃含量高的馆分直接生产芳烃。使用选择性好、稳定性高的催化剂，流程简单、能耗低，称为a工艺。其技术特点有：（1）原料中烯烃经二聚和脱氢环化过程而生成芳烃的反应比烷烃脱 C4 and C5 fractions from thermal cracking and fluid catalytic cracking units contain 30% to 80% of olefins, and Japan’s Sanyo Petrochemical uses these low-value fractions of olefins to directly produce aromatics. The use of good selectivity, high stability of the catalyst, the process is simple, low energy consumption, known as a process. Its technical features are: (1) the raw material olefin by dimerization and dehydrocyclization process to generate aromatics reaction than the alkane off