Cost-effective and fast synthesis of Sn-β zeolite with less silanol defects for efficient conversion of glucose to methyl lactate

• Published in: Molecular catalysis Vol. 524; p. 112259
• Main Authors: Qu, Hongjin, Zhou, Shengqiang, Su, Yunlai, Yang, Xiaomei, Zhou, Lipeng
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.05.2022
• Subjects: Biomass; Lewis acid; Methyl lactate; Quasi-solid synthesis; Sn-β zeolite; Lewis acid; Methyl lactate; Biomass; Sn-β zeolite; Quasi-solid synthesis
• ISSN: 2468-8231; 2468-8231
• DOI: 10.1016/j.mcat.2022.112259

•Sn-β zeolite was prepared by a fast and cost-effective quasi-solid-phase method.•The time required for complete crystallization of zeolite reduced from 7 days to 3 days.•The Lewis acid density of Sn-β zeolite increased as the addition of Mg2+.•Mg2+ facilitated the Si-OH defects of zeolite reduced notably.•A considerable yield of MLA (54.4%) was acquired over 1Mg-Sn-β-3d. Sn-β with strong Lewis acid sites is considered as the state-of-the-art solid catalyst for converting glucose to alkyl lactate. However, the extensive use of organic template and mineralizing agent and long preparation period in the synthesis of Sn-β brought serious environmental pollution and high synthesis cost. Herein, a cost-effective and fast synthesis strategy using fewer organic template and mineralizing agent, fumed silica as Si source, Mg2+ cation as crystallization promoter and without additional solvent, is proposed to alleviate the aforementioned shortcomings. The results reveal that highly crystalline Mg-Sn-β can be synthesized in 3 days from the gel of 0.005MgO/0.005SnO2/SiO2/0.15TEAOH/0.15NH4F/3.75H2O. Besides accelerating the crystallization, it is found that Mg2+ cation facilitated Sn4+ incorporation into the framework site and lessened the silanol defects of zeolite notably. For conversion of glucose to methyl lactate (MLA), a higher yield of MLA was obtained over 1Mg-Sn-β-3d (54.4%) compared with Sn-β-H-7d (37.2%) and Sn-β-7d (41.3%). Sn-β zeolite was synthesized by quasi-solid-phase method using fewer organic template and mineralizing agent with Mg2+ as crystallization promoter. The time required for complete crystallization of zeolite reduced from 7 days to 3 days and the framework Sn4+ increased and Si-OH defects reduced notably with the introduction of Mg2+. [Display omitted]