With the growing demand for propylene and the rapid depletion of petroleum resources, the methanol-to-propylene (MTP) reaction has aroused much interest in the industrial and academic research fields as an alternative route to produce propylene. Developing a highly efficient MTP catalyst by adopting a facile, efficient route is currently an important research goal. It is clear that the synthesis of a hierarchical micro-meso-macroporous ZSM-5 zeolite is regarded as the ideal strategy owing to its ability to minimize coke formation and to produce maximal catalytic efficiency in the MTP reaction.

In this study, a superior MTP catalyst with a hierarchical micro-meso-macroporous structure (denoted as M-ZSM-5) has been successfully developed based on the passivation effect and the strong self-condensation of the short-chain organosilane 3-aminopropyltrimethoxy-silane (APTES) on the surfaces of nanocrystals in a quasi-solid-state system. This environmentally friendly synthetic strategy is operationally simple, with a high yield (above 80 %) and low cost and thus has considerable potential for industrial applications. In the quasi-solid-state system, APTES not only induced the formation of ultrafine nanocrystals but also ensured that these ultrafine nanocrystals were assembled in situ into hierarchical micro-meso-macroporous ZSM-5 zeolites. When applied to the methanol-to-propylene (MTP) reaction, the synthesized MZ-x (x = 1–5) zeolites exhibited a longer catalytic lifetime (31 h - 89 h) (at a high weight hourly space velocity of 8 h-1) than that of a commercial ZSM-5 catalyst (denoted as C1Z-1)(11 h), which are nearly three times and eight times longer than that of the C1Z-1 sample. In addition, the MZ-x (x = 1–5) catalysts also present a slightly higher propylene selectivity (39.92 %–41.89 %), butylene selectivity (22.29 %–23.65 %) and light olefins (C2= − C4 = ) selectivity (69.19 % ~ 71.43 %) than that of the C1Z-1 (39.86 %, 21.70 %, 68.46 %). These results were attributed to the abundant mesopores and macropores of M-ZSM-5 built by the ultrafine nanocrystals, offering a shorter diffusion path and more-accessible active sites for reaction.

随着对丙烯需求的增长和石油资源的迅速消耗，甲醇制丙烯（MTP）反应引起了工业和学术研究领域的极大兴趣，将其作为生产丙烯的替代途径。通过采用简便，有效的途径开发高效的MTP催化剂目前是重要的研究目标。显然，由于其具有最小化焦炭形成并在MTP反应中产生最大催化效率的能力，分级合成的微介孔大分子ZSM-5沸石被认为是理想的策略。

在这项研究中，基于钝化效应和短链有机硅烷3-氨丙基三甲氧基的强自缩合作用，成功开发了具有分层的微介孔-大孔结构（表示为M-ZSM-5）的高级MTP催化剂。准固态系统中纳米晶体表面上的-硅烷（APTES）。这种环境友好的合成策略操作简单，产率高（超过80％）且成本低，因此在工业应用中具有巨大的潜力。在准固态系统中，APTES不仅诱导了超细纳米晶体的形成，而且确保了这些超细纳米晶体在原位组装成分层的微介孔大孔ZSM-5沸石。当应用于甲醇制丙烯（MTP）反应时，合成的MZ-x（x = 1-5）沸石比商用ZSM-5催化剂（表示为8 h-1的高重时空速）具有更长的催化寿命（31 h-89 h）（在8 h-1的高重时空速度下）。 C1Z-1）（11 h），是C1Z-1样品的近三倍和八倍。此外，MZ-x（x = 1-5）催化剂还具有较高的丙烯选择性（39.92％–41.89％），丁烯选择性（22.29％–23.65％）和轻质烯烃（C2 =-C4 =）选择性（69.19％〜71.43％）比C1Z-1（39.86％，21.70％，68.46％）高。这些结果归因于由超细纳米晶体构建的M-ZSM-5的丰富的中孔和大孔，提​​供了更短的扩散路径和更易接近的反应活性位点。