ZSM-5分子筛在MTP反应中的催化性能

Catalytic performance of ZSM-5 zeolite in the reaction of methanol to propylene

合成了3种不同晶粒尺寸的ZSM-5分子筛,并制得MTP催化剂,对ZSM-5分子筛催化剂在MTP反应中的性能进行系统研究。采用XRD、SEM、N2物理吸附和TGA等对ZSM-5分子筛催化剂进行表征,发现小晶粒的ZSM-5分子筛具有良好的抗积炭性能,在MTP反应中具有较高的稳定性。采用小晶粒分子筛制成的催化剂,考察反应工艺条件对催化剂催化性能的影响,结果表明,丙烯选择性随反应温度和空速提高而增加,降低反应压力和提高水醇质量比也有利于提高丙烯选择性,为调整MTP工艺的产物分布和优化反应工艺条件提供了技术依据。

A series of ZSM-5 zeolite samples with different crystal sizes were synthesized and MTP cata- lysts were prepared. The catalytic performance of the catalysts in MTP process was studied in detail. ZSM-5 zeolite catalysts were characterized by XRD, BET, SEM, and TGA techniques. The results showed that ZSM-5 zeolite catalyst with small crystal size exhibited excellent durability in the catalytic conversion of methanol,which might be due to its high tolerance ability for coke. With the small crystal size ZSM-5 catalyst, different process conditions were studied. The results indicated that the selectivity to propylene was improved with the increase of reaction temperature and space velocity of methanol ; the enhancement of the mass ratio of water to methanol and decrease of reaction pressure were also beneficial to increasing the selectivity to propylene. The technical basis of adjusting product distribution for MTP process and optimizing process condition were obtained.