Hongmin Sun

Advances in development and industrial applications of ethylbenzene processes

Abstract The benzene alkylation process for the production of ethylbenzene has undergone significant improvements during recent decades. Various environmentally benign zeolite-catalyzed ethylbenzene processes, including ZSM-5-zeolite-based vapor-phase ethylbenzene processes and Y-, β-, and MCM-22-zeolite-based liquid-phase processes, have been developed and commercialized. Pure ethylene, ethanol, and dilute ethylene have been used as ethylation agents. Here, the development and industrial application of alkylation catalysts and benzene ethylation techniques are summarized, and some other promising innovations are discussed. Recent advances in benzene alkylation over hierarchical zeolites with improved access to active sites and molecular transport are also covered. Zeolites with short diffusion lengths are promising candidates as better alkylation catalysts. The key point is how to obtain such materials easily and economically. The structure-activity relationships of commercial zeolites in these processes are discussed. Liquid-phase processes catalyzed by β and MCM-22 are more profitable than vapor-phase processes catalyzed by ZSM-5.

Synthesis and crystal growth mechanism of ZSM-22 zeolite nanosheets

ZSM-22 zeolite nanosheets with a thickness of about 10 nm were synthesized through hydrothermal crystallization without any special additives. The formation of the nanosheet crystals follows a multi-step crystallization mechanism through aggregation and fusion of the elementary nanorods. The inhomogeneous distribution of aluminum might be the key factor that induces the formation of the nanosheet crystals.

A Facile and Green Method for the Synthesis of SFE Borosilicate Zeolite and Its Heteroatom‐Substituted Analogues with Promising Catalytic Performances

Synthesis of SFE-type borosilcate zeolite was successfully carried out using a commercially available low-cost organic structure directing agent (OSDA) with ultra-low OSDA and water contents within a short crystallization time. Heteroatom (Al, Ti, V, or Fe)-substituted SFE-type zeolite analogues were also directly synthesized for the first time. The obtained Al containing zeolites exhibited promising catalytic performances in the disproportionation of isopropylnaphthalene.