Chiral zeolite beta: structure, synthesis, and application
Zeolite beta is an intergrowth of two or three polymorphs, including chiral polymorph-A, achiral polymorph-B, and polymorph-C. Chiral polymorph-A of zeolite beta is highly desired because of its potential applications in enantioseparation and asymmetric catalysis. However, it is still impossible to obtain the pure polymorph-A of zeolite beta. This review comprehensively summarizes and evaluates the recent progress in the studies of chiral zeolite beta. An insight into the intergrowth structure of zeolite beta revealing the chiral feature of polymorph-A is provided. The synthesis of chiral polymorph-A enriched zeolite beta and the corresponding chiral applications are discussed. The unsolved challenges are outlined and the areas for future exploration in the synthesis of polymorph-A of zeolite beta are suggested.