Simultaneous Mesoporosity Generation and Lewis Acidity Enhancement in Zr‐Based Metallosilicalite for Promoting the Conversion of Ethanol‐Acetaldehyde to 1,3‐Butadiene

Abstract

Zr based metallosilicalites, especially Zr-ß, is promising catalyst for the conversion of ethanol to 1,3-butadiene, which is considered to be a sustainable alternative to petroleum steam cracking. However it is suffering from deactivation derived from coking and unsatisfied catalytic activity derived from deficient Lewis acidity. For these issues, a dissolution-recrystallization process through tetraethyl ammonium hydroxide treatment (TEAOH) for enhancing porosity and Lewis acidity of Zr-ß zeolite was developed in this study. A balance of dissolution and recrystallization existed in this process, which was produced by OH À etching and templating of TEA + ions, creating additional mesoporosity. Zirconium active sites maintained tetrahedral coordination, while the Lewis acidity was enhanced by creating higher proportion open sites in framework. The recrystallized Zr-ß exhibited higher catalytic activity and stability in the conversion of ethanol-acetaldehyde to butadiene due to the compromise of microporosity and mesoporosity, as well as the appropriate enhancement of Lewis acidity.

Perspectives on Recent Advances in Hierarchical Zeolites for Bioethanol Conversion to Chemicals, Jet Fuels, and Carbon Nanotubes

“…More recently, Jiang and co-workers 120 proposed a new modification of hierarchical Zr/BEA zeolite by the dissolutionrecrystallization process (Zr-β-0.5 M TEAOH). These treatment processes enable to create the active open sites of Zr, as confirmed by the CD 3 CN-IR spectra (Figure 9A).…”

“…(A) CD 3 CN-IR spectra and (B) Catalytic activity and product selectivity of Zr-β-0.5 M TEAOH and Zr-β. Reproduced with permission from ref . Copyright 2023 Wiley-VCH GmbH.…”