Hierarchical zeolites comprising orthogonally stacked bundles of zeolite nanosheets for catalytic and adsorption applications

Albert Chang; Tsung-Cheng Yang; Ming-Yi Chen; Hsu-Ming Hsiao; Chia-Min Yang

doi:10.1016/j.jhazmat.2020.123241

Hierarchical zeolites comprising orthogonally stacked bundles of zeolite nanosheets for catalytic and adsorption applications

J Hazard Mater. 2020 Dec 5:400:123241. doi: 10.1016/j.jhazmat.2020.123241. Epub 2020 Jun 17.

Authors

Albert Chang¹, Tsung-Cheng Yang², Ming-Yi Chen¹, Hsu-Ming Hsiao¹, Chia-Min Yang³

Affiliations

¹ Department of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan.
² Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, Hsinchu 30013, Taiwan.
³ Department of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan; Frontier Research Center on Fundamental and Applied Sciences of Matters, National Tsing Hua University, Hsinchu 30013, Taiwan. Electronic address: cmyang@mx.nthu.edu.tw.

PMID: 32585524
DOI: 10.1016/j.jhazmat.2020.123241

Abstract

The synthesis of hierarchical MFI zeolites comprising orthogonally stacked bundles of zeolite nanosheets using a new type of triblock structure-directing agents (SDAs) was reported. The textural properties, including the degree of nanosheet branching and the spacing between adjacent nanosheets, could be controlled by changing the length of the linkers in the triblock SDAs. The hierarchical pure-silica silicalite-1 materials exhibited high and stable catalytic activity for the vapor-phase Beckmann rearrangement of cyclohexanone oxime with high selectivity of ε-caprolactam. On the other hand, the hierarchical ZSM-5 materials showed high adsorption capacity of Pb²⁺ ion following a Langmuir-type adsorption behavior. After being deposited with Pd nanoparticles, the hierarchical Pd/ZSM-5 nanocomposites exhibited high activity in the aqueous-phase hydrogenation of phenol to cyclohexanone at room temperature. The results show promise of the disclosed hierarchical zeolites for catalytic and adsorption applications.

Keywords: Adsorbent; Green chemistry; Heterogeneous catalysis; Hierarchical zeolite; Lead.