Conversion of Dimethyl Ether to Olefins over Nanosized Mordenite Fabricated by a Combined High-Energy Ball Milling with Recrystallization

Abstract

Fabrication of cost-effective catalysts is one of the key strategies to monetize natural gas derivatives such as dimethyl ether to olefins. In this study, the particle size of natural mordenite (MOR) was reduced into micro- and nanosize by high-energy ball milling with variation in milling time. Furthermore, the selected milled MOR was recrystallized by using a silicate solution that favored the growth of the mordenite phase to recover the demolished mordenite structure. The mesopore volume and external surface area were increased significantly after milling treatments and remained large even after recrystallization. A high conversion of dimethyl ether was obtained over the recrystallized MOR (99.7%) and milled natural MOR (54.1%) as compared to the parent (1.2%). Moreover, the milling only and the milling–recrystallization processes improved selectivity toward olefins and prolonged catalyst lifetime. The reduced particle size combined with the hierarchical porous and acidity effectively enhanced catalyst...