不同元素改性ZSM-5对低碳烯烃催化裂解的影响

Effect of Different Element Modified ZSM-5on Catalytic Cracking of Low Carbon Olefin

利用原位红外光谱检测研究异丁烯在改性前后ZSM-5分子筛上的反应差异,初步探究其反应机理和最佳反应时间。实验结果表明,改性后的分子筛弱酸量增多。其中用Ca改性的分子筛不仅可以有效控制氢转移反应抑制芳烃的生成,同时还可以促进脱氢裂解反应的发生;而用K改性后的分子筛在裂解反应中效果并不明显。

In this paper,in-situ infrared spectroscopic detection was used to study the reaction difference of isobutylene on the ZSM-5 molecular sieve before and after modification,and the preliminary investigation of its reaction mechanism and optimal reaction time.The experimental results show that the weak acid content of the modified molecular sieve increases.Among them,molecular sieves modified with Ca can not only effectively control the hydrogen transfer reaction to suppress the generation of aromatics,but also promote the occurrence of dehydrogenation splitting reactions;while the molecular sieves modified with K have no obvious effect in the splitting reaction.