Cocrystalline Synthesis of ZSM‐5/ZSM‐11 and Catalytic Activity for Methanol to Propylene

• Published in: Crystal research and technology (1979) Vol. 55; no. 7
• Main Authors: Tao, Jiayi, Zhang, Jianli, Fan, Su‐Bing, Gao, Xinhua, Ma, Qingxiang, Zhao, Tian‐Sheng
• Format: Journal Article
• Language: English
• Published: 01.07.2020
• Subjects: Al distribution; B acidity; cocrystalline zeolites; methanol to propylene reaction; ZSM‐5/11
• ISSN: 0232-1300; 1521-4079
• DOI: 10.1002/crat.202000027

Cocrystalline ZSM‐5/ZSM‐11 zeolite is hydrothermally synthesized at crystallization temperatures of 170 and 130 °C, respectively, in order to regulate the acidity as well as the framework Al distribution to enhance the propylene formation from methanol. ZSM‐5/11‐170 has analogous textural properties to ZSM‐5 but with increased strong Brønsted acid amount, raising the propylene selectivity by 49% in the methanol to propylene reaction at 480 °C, attributed to the increasing Al distribution in the straight channels by introduction of ZSM‐11 into ZSM‐5. With crystallization to 130 °C, the strong Brønsted acid amount of ZSM‐5/11‐130 is decreased by 82% compared with ZSM‐5/11‐170. The selectivity of propylene is increased to 38.25%, along with the decrease in the selectivity of ethylene and C5–C9. Cocrystalline ZSM‐5/ZSM‐11 zeolite is hydrothermally synthesized to increase the Al distribution in the straight channels. Lower crystallization temperature reduces the strong Brønsted acid amount. These two changes promote the propylene production from methanol.