Recent advances of pore system construction in zeolite-catalyzed chemical industry processes

Abstract

The kaleidoscopic applications of zeolite catalysts (zeo-catalysts) in petrochemical processes has been considered as one of the major accomplishments in recent decades. About twenty types of zeolite have been industrially applied so far, and their versatile porous architectures have contributed their most essential features to affect the catalytic efficiency. This review depicts the evolution of pore models in zeolite catalysts accompanied by the increase in industrial and environmental demands. The indispensable roles of modulating pore models are outlined for zeo-catalysts for the enhancement of their catalytic performances in various industrial processes. The zeolites and related industrial processes discussed range from the uni-modal micropore system of zeolite Y (12-ring micropore, 12-R) in fluid catalytic cracking (FCC), zeolite ZSM-5 (10-R) in xylene isomerization and SAPO-34 (8-R) in olefin production to the multi-modal micropore system of MCM-22 (10-R and 12-R pocket) in aromatic alkylation and the hierarchical pores in FCC and catalytic cracking of C4 olefins. The rational construction of pore models, especially hierarchical features, is highlighted with a careful classification from an industrial perspective accompanied by a detailed analysis of the theoretical mechanisms.

Creating Accessible Active Sites in Hierarchical MFI Zeolites for Low‐Temperature Acid Catalysis

“…[1,2] Direct benefits of the incorporation of micropores and mesopores within a single porous architecture have been demonstrated in key catalytic processes for petroleum refining, catalytic cracking of hydrocarbons, isomerization and fine chemical applications. [3][4][5] Many synthetic strategies (e.g. bottomup and top-down approaches and zeolite recrystallization) have been explored for the formation of hierarchical zeolites, which contain interconnected micro-and mesopores, in prospect of possible industrial applications.…”

Understanding Zeolites Catalyzed Methanol‐to‐Olefins Conversion from Theoretical Calculations

“…[1,2] This is particularly signifi-cant in China as we are short in crude oil and rich in coal. They are mainly produced from petroleum by steam cracking or fluid catalytic cracking (FCC) technologies.…”

Micro/Mesoporous Zeolitic Composites: Recent Developments in Synthesis and Catalytic Applications

“…Desilication of the HZSM-5 (HZ-P) with tetramethyl-ammonium hydroxide (TMAOH) and tetraethyl-ammonium hydroxide (TEAOH) (denoted as HZ-MT and HZ-ET respectively) and subsequent recrystallization (denoted as HZ-MR and HZ-ER respectively): (a) Schematic illustration of the catalytic cracking of n-dodecane over HZs and (b) Conversion of n-dodecane over HZCs catalysts prepared by deposition of HZs onto the inner surface of the stainless steel tubular reactor. Adapted with permission from [7]. Copyright Royal Society of Chemistry, 2015.…”

“…Among them, about 20 zeolites such as Y (FAU), ZSM-5 (MFI), mordenite (MOR), beta (BEA), MCM-22 (MWW) etc. have been widely used as heterogeneous catalysts in a good number of industrial processes, e.g., fluid catalytic cracking (FCC), alkylation, methanol-to-hydrocarbons (MTH), and hydroconversion processes [3][4][5][6][7]. The success of zeolites in catalysis primarily stems from their outstanding properties including crystallinity, large inner surface area, superior hydrothermal stability, tunable acidic properties, and well-defined pore sizes with shape-selectivity.…”