Recent advances in synthetic strategies and physicochemical modifications of SSZ-13 zeolites: A review

Abstract

Aluminosilicate zeolites are widely recognized as an industrially important crystalline microporous material. Among them, small-pore SSZ-13 stands out as an artificial aluminosilicate zeolite with CHA topology. Since its invention in 1985, SSZ-13 zeolite has garnered significant attention in both academia and industry due to its exceptional performance in heterogeneous catalysis, gas adsorption and separation. Modification of its physicochemical properties to meet the diverse requirements of various application scenarios has become a prominent topic in zeolite research. Considerable efforts have been devoted to alleviating the diffusion limitations inherent in micropores by downsizing crystal size or introducing additional mesopores and/or macropores to construct hierarchical structures. Regulating framework Al atoms in isolation or pairing introduces remarkable catalytic or adsorptive diversity into compositionally similar SSZ-13 zeolites. The conventional synthesis of SSZ-13 zeolite, which involves the use of expensive and toxic N,N,N-trimethyl-1-adamantylammonium hydroxide (TMAdaOH) as an organic structure-directing agent (OSDA) and a hydrothermal crystallization process lasting typically more than four days, severely hinders its cost-effective utilization. In response, extensive research endeavors have been dedicated to developing innovative synthetic approaches for SSZ-13 zeolites aimed at greener, more efficient, and economically viable production. This article presents a comprehensive overview of recent research developments in the field of SSZ-13 zeolites, encompassing novel synthetic methods, hierarchical engineering, nanocrystal technology, Al distribution, fast synthesis, and cost reduction techniques, aiming to provide valuable insights and guidance to relevant researchers.