Zeolites

Catalytic role of different pore systems in MCM-49 zeolite for liquid alkylation of benzene with ethylene

“…It has been reported that the RC of zeolite can be effectively improved with the mild alkali-treatment conditions [38] and then decreases with harsh treatment conditions [46,47]. We also observe a similar phenomenon.…”

“…Since most L acid sites are located within the supercages of HM (Table 2), the oligomerization and coking reaction of ethylene will cover some of strong acid sites, resulting in the deactivation of HM. In addition, when zeolites are synthesized or post-treated, the noncrystalline raw materials or amorphous silica-alumina generated in the calcination process is usually included [36][37][38]. These amorphous silica-alumina species might deposit on the surface of MCM-49 zeolite and cause partial blockage of the 10MR opening of the supercages [39].…”