钾-钙双金属改性对HZSM-5分子筛催化甲醇制丙烯的影响

Effect of potassium and calcium on catalytic performance of HZSM-5 zeolite for conversion of methanol to propene

针对甲醇制丙烯反应体系,研究了不同金属、双金属改性的HZSM-5的催化性能。结果表明,钾改性提高了催化剂的稳定性和催化性能,当钾改性液的质量分数为2%时,改性效果最好,在此基础上,以2%K-HZSM-5作为不同钙负载的改性对象。结果表明,钾钙共同改性,具有较好的协同改性效果,大大提高了丙烯的选择性,有效的降低了乙烯和副产物的产率。

HZSM-5 Zeolite was modified with different metals and bimetallic. Methanol to olefin over modified HZSM-5 catalysts was carried in a continuous flow fixed bed reactor. The results showed that K modification enhanced both catalytic stability and the selectivity of propylene, whereas excessive K loadings resuits in declining catalytic behaviors. The optimum K loading was 2%, therefore different Ca loadings of 2% K-HZSM-5 were experimented. The results showed that K-Ca-HZSM-5 had good synergistic modification effect on stability and selectivity to propylene, and decreased the production of ethene and other sideproducts.