催化裂解过程丙烯选择性的影响因数探究

生产丙烯的催化裂解技术已在工业装置上得到广泛应用，该技术的干气产率随着丙烯产率的增加而增加，因此如何在增产丙烯的同时降低干气产率、提高过程的丙烯选择性，成为催化裂解技术亟需破解的难题。通过研究催化裂解过程丙烯生成的反应化学以及影响丙烯选择性的反应参数，对DCC技术进行了改进，开发出低干气产率、高丙烯选择性的增强型催化裂解（DCC plus）技术。结果表明，与DCC技术相比，DCC plus技术的干气和焦炭产率可以分别降低159百分点和249百分点，丙烯产率增加167百分点，丙烯/干气产率比增加了058百分点。DCC plus 技术的丙烯选择性明显提高，并已在国内外工业装置上得到应用。

Study on Influencing Factors of Propylene Selectivity in Deep Catalytic Cracking Process

The catalytic cracking technology for propylene production has been widely applied in commercial practices, and the dry gas yield increases with the increase of propylene yield in the technology. Consequently, how to increase the yield of propylene and reduce the dry gas yield and improve the selectivity of propylene became an urgent problem to be solved. By investigating the reaction chemistry of propylene formation during a deep catalytic cracking process and the reaction parameters affecting propylene selectivity, enhanced deep catalytic cracking (DCC plus) technology with low dry gas yield and high propylene selectivity was developed based on DCC technical improvement. The experimental results showed that compared with DCC technology, the dry gas and coke yields of DCC plus can be reduced by 159 percentage points and 249 percentage points, respectively, the propylene yield is increased by 167 percentage points, and the yield ratio of propylene/dry gas is increased by 058 percentage points. The propylene selectivity of DCC plus technology has been greatly improved, and it has been applied in the domestic and foreign commercial units.