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One-Step Synthesis of Hierarchical ZSM-5 Using Cetyltrimethylammonium as Mesoporogen and Structure-Directing Agent.

ABSTRACT: Hierarchical ZSM-5 zeolite is hydrothermally synthesized in a single step with cetyltrimethylammonium (CTA) hydroxide acting as mesoporogen and structure-directing agent. Essential to this synthesis is the replacement of NaOH with KOH. An in-depth solid-state NMR study reveals that, after early electrostatic interaction between condensed silica and the head group of CTA, ZSM-5 crystallizes around the structure-directing agent. The crucial aspect of using KOH instead of NaOH lies in the faster dissolution of silica, thereby providing sufficient nutrients for zeolite nucleation. The hierarchical ZSM-5 zeolite contains mesopores and shows excellent catalytic performance in the methanol-to-hydrocarbons reaction.

SUBMITTER: Meng L

PROVIDER: S-EPMC5437811 | biostudies-literature | 2017 May

REPOSITORIES: biostudies-literature

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One-Step Synthesis of Hierarchical ZSM-5 Using Cetyltrimethylammonium as Mesoporogen and Structure-Directing Agent.

Meng Lingqian L Mezari Brahim B Goesten Maarten G MG Hensen Emiel J M EJM

Chemistry of materials : a publication of the American Chemical Society 20170418 9

Hierarchical ZSM-5 zeolite is hydrothermally synthesized in a single step with cetyltrimethylammonium (CTA) hydroxide acting as mesoporogen and structure-directing agent. Essential to this synthesis is the replacement of NaOH with KOH. An in-depth solid-state NMR study reveals that, after early electrostatic interaction between condensed silica and the head group of CTA, ZSM-5 crystallizes around the structure-directing agent. The crucial aspect of using KOH instead of NaOH lies in the faster di ...[more]

PMID: 28539702

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