MATERIALS CHEMISTRY AND PHYSICS
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2022
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IF 4.778
Xiaomei Yang,Xu Chen,Bin Lv,Yunlai Su,Lipeng Zhou
Sn-Beta zeolite is an excellent catalyst for the transformation of biomass derived carbohydrates. However, the long synthesis time restricted its application. Here, alkaline (earth) salt was used as promoter to accelerate the crystallization of Sn-Beta. Different alkaline (earth) salts and the amount of MgCl 2 were investigated. The properties of the synthesized samples were characterized by various techniques and compared with Sn-Beta, and the catalytic performance was investigated for the conversion of glucose to methyl lactate (MLA). The results indicate that a small amount of alkaline (earth) salt, especially MgCl 2 , promoted dramatically the crystallization of Sn-Beta. The full crystallization time was shortened from 15 d to 5 d with the aid of MgCl 2 ( n Mg / n Sn of 1.0) for Sn-Beta with n Si / n Sn of 100. Sn 4+ cations were incorporated into the framework sites, while Mg 2+ cations replaced the protons of silanol defects. Mg–Sn-Beta with strong Lewis acid sites and less silanols showed high activity and selectivity for glucose conversion to MLA. The yield of MLA is 20% over the fully crystallized Sn-Beta at 120 °C for 15 h and glucose concentration of 3.1 wt%, which increased significantly to 44% over the fully crystallized 1 Mg–Sn-Beta. Furthermore, Mg–Sn-Beta is stable and recyclable.
研究领域:
催化化学
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生物质转化
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DOI
高影响因子
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
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2021
·Vol. 96
·期 8
·2238-2248
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IF 3.174
Xiao-Yang Yue,Hui-Fang Ren,Chengming Wu,Jun Xu,Jifan Li,Chun-Ling Liu,Wen-Sheng Dong
BACKGROUND Methyl lactate is widely applied in the chemical, food, cosmetics and pharmaceutical industries. The conversion of carbohydrates over heterogeneous catalysts to methyl lactate is a promising environmentally benign process. RESULTS Hierarchical Sn-Beta zeolite (Sn-Beta) and corresponding bimetal-doped Beta zeolites (M-Sn-Beta; M = Zn, In, La, Ga, Ni) were prepared via a novel modified hydrothermal synthesis method to convert carbohydrates into methyl lactate. The introduction of Zn into Sn-Beta considerably improved the yield of methyl lactate from glucose, while for the catalysts containing In, La, Ga and Ni, such improvements were not observed. CONCLUSIONS A methyl lactate yield reaching up to 66.7% was obtained over Zn-Sn-Beta at 220 °C for 6 h. The enhanced catalytic performance was attributed to high Lewis acid density and strength, together with synergistic effects between framework Sn 4+ and Zn 2+ ions of Zn-Sn-Beta. Additionally, Zn-Sn-Beta demonstrated fructose and sucrose conversion into methyl lactate with yields of 68.4% and 70.0%, respectively. The Zn-Sn-Beta catalyst could be re-used at least five times with only a slight loss of methyl lactate yield. © 2021 Society of Chemical Industry (SCI).
研究领域:
化学工程
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催化科学
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产品关联
DOI
高影响因子
CELLULOSE
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2019
·Vol. 26
·期 17
·9135-9147
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IF 3.917
Zhou Shengqiang,Yang Xiaomei,Zhang Yali,Jiang Lingyun,Zhou Lipeng,Lu Tianliang,Su Yunlai
Abstract One-pot conversion of cellulose to valued-added platform chemicals such as alkyl levulinate is a promising and challenging process of biomass utilization due to the insolubility of cellulose in alcohol. In this work, commercial heteropoly acid combined with postsynthesized Sn-Beta zeolite was employed to transform cellulose to methyl levulinate (MLE) in one pot. The synergistic catalysis of the homogeneous strong Brønsted (B) acid and the solid strong Lewis (L) acid can effectively realize the depolymerization of solid cellulose and the subsequent isomerization, dehydration and hydration steps to MLE. 55% and 62% of MLE yields were obtained from α-cellulose and microcrystalline cellulose, respectively, at 160 °C for 10 h. Various carbohydrates besides cellulose can also be efficiently converted to MLE in high yields over the bifunctional catalyst system. The effects of the amount of B acid and L acid, the reaction temperature and time and the amount of cellulose on the production of MLE were investigated in detail. Finally, the reaction pathway of cellulose to MLE was revealed. Recyclability tests indicated that the binary catalyst can be reused without decrease of catalytic activity. Graphic abstract
研究领域:
生物质化学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2021
·
IF 4.094
Shengqiang Zhou,Lipeng Zhou,Yunlai Su,Xiaomei Yang,Hao He
Sn-Beta zeolite is a promising heterogeneous Lewis acid catalyst. Hydrothermal synthesis of Sn-Beta(TEOS) using tetraethyl orthosilicate (TEOS) as silica source is a classical method. However, the hydrolysis of TEOS generates considerable ethanol, which is unfavorable for scalable production of Sn-Beta. Herein, cheap fumed silica and silica sol were used as Si sources to synthesize Sn-Beta and compared with that synthesized from TEOS . The crystalline phase, morphology, physicochemical properties, and the state of Sn were characterized. It was found that Sn-Beta can be successfully prepared with fumed silica and silica sol as well as TEOS as silica source. Sn was introduced into the framework of these samples. Sn-Beta synthesized from fumed silica (Sn-Beta(FS)) and silica sol (Sn-Beta(Sol)) had similar crystallization behavior and full crystallization time as well as morphology, crystal size with that from TEOS. Sn-Beta(Sol) has less silanols and lowest ratio of open/closed tin site among these samples. It exhibited higher catalytic activity for the conversion of glucose to methyl lactate and lower catalytic activity for the isomerization of glucose as compared with the other two samples. Sn-Beta(FS) showed similar catalytic performance in the studied reactions with Sn-Beta(TEOS).
研究领域:
材料科学
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催化化学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Xiaolong Liu,Jiaxing Zhang,Xue Liu,Kaixuan Yang,Ting Su,Hongying Lü,Peng Wu,Zhiguo Zhu
Catalytic conversions of cyclic ketones into lactones by the Baeyer–Villiger oxidation are particularly attractive for practical applications because catalytic transformations minimize reactant use as well as waste production while simplify processing conditions. Understanding the unique behaviors of highly mesoporous Sn-Beta zeolite catalyst during Baeyer–Villiger oxidation is a challenging research topic. Herein, highly mesopore single-crystalline Sn-Beta zeolite (Sn-Beta-2s) is hydrothermally synthesized via our developed two-step interzeolite transformation strategy. The synthesis mechanism obeys dissolution–recrystallization process, where the degradation step is essential to prepare Sn-Beta-2s zeolite with abundant mesoporous and relatively high hydrophobicity. This single-crystalline Sn-Beta zeolite is adopted to the Baeyer-Villiger oxidation of cyclic ketones as heterogeneous Lewis acid catalyst. Structure-performance relationship reveals that the diffusion performance dominates the product selectivity over three Sn-Beta zeolites. Through the investigation of catalytic mechanism by in-situ FT-IR spectra and DFT calculations, it is found that carbonyl group is activated by zeolitic framework Sn. As for the bulky tert -butyl hydroperoxide oxidant, the reaction can be only triggered on the zeolite surface due to the severe steric constraints within zeolite channels, accounting for the excellent catalytic activity of Sn-Beta-2s zeolite with nanocrystalline nature.
研究领域:
化学工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
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2020
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IF 7.632
Bo Tang,Shuang Li,Wei-Chao Song,En-Cui Yang,Xiao-Jun Zhao,Naijia Guan,Landong Li
In this work, BEA-type hierarchically structured stannosilicate zeolite Sn-Beta-H was developed, which involved alkali-induced degradation of all-silica Beta (Si-Beta) and self-assembly of the resultant Si-Beta fragments with SnCl2·2H2O in the hydrothermal condition templated with tetraethylammonium hydroxide (TEAOH) and polydiallydimethylammonium chloride (PDADMAC). The synthesized Sn-Beta-H zeolite was comprehensively characterized by means of XRD, N2 physisorption, TEM, UV–vis, XPS, TG, DRIFT, and FTIR spectroscopy with pyridine and deuterated acetonitrile adsorption. The Lewis acidity related to isolated tetrahedrally coordinated Sn species in the hierarchical porous Beta framework was revealed, which existed in the form of partially hydrolyzed and framework-integrated species. The Sn-Beta-H zeolite worked efficiently in the catalytic transformation of a series of carbohydrates into methyl lactate, outperforming the microporous Sn-Beta and postsynthesized mesoporous meso-Sn-Beta counterparts. The influence parameters such as mesoporosity, hydrophilicity/hydrophobicity, and Lewis acidity on the glucose conversion were studied in detail.
研究领域:
催化化学
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材料科学
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产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
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2017
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IF 5.951
Jian Zhang,Liang Wang,Guoxiong Wang,Fang Chen,Jie Zhu,Chengtao Wang,Chaoqun Bian,Shuxiang Pan,Feng-Shou Xiao
Enhancing the yield of alkyl lactate from sugars is in great demand but challengeable to accomplish. Here we report a facile but efficient route to make this by employing a hierarchical and Sn-containing Beta zeolite (Sn-Beta-H). The hierarporosity in the Sn-Beta-H facilitates the conversion of sugars into important intermediates for producing alkyl lactate in the competition with undesirable side reactions, thus outperforming the conventional Sn-zeolite catalysts in yielding alkyl lactate from a wide scope of sugars. Particularly, the yield of alkyl lactate could reach as high as 72.1% from sucrose. Importantly, the Sn-Beta-H is stable and can be easily recycled for five times with constant catalytic performances.
研究领域:
化学工程
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催化科学
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可再生资源转化
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DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
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2019
·
IF 4.182
Qingrun Meng,Jiaxu Liu,Guang Xiong,Xinyao Li,Liping Liu,Hongchen Guo
The Sn-Beta zeolite is an efficient Lewis acid catalyst for a wide range of chemical reactions. Here a seed-free aerosol-assisted hydrothermal strategy is used to synthesize plate-like Sn-Beta zeolite with higher tin content. A majority of Sn species were transformed into the framework of Beta zeolite as the desired tetrahedral coordination state, which creates strong Lewis acid sites. Moreover, the diffusion property of the Sn-Beta zeolite can be further improved by a mild base-surfactant (NH 3 ˙ H 2 O-CTAB) treatment. The addition of CTAB can not only narrow the mesopore distribution but also prevent the excessive loss of Sn species. The obtained hierarchical Sn-Beta zeolite exhibits an enhanced catalytic performance in the Baeyer–Villiger oxidation of bulky ketone.
研究领域:
催化材料
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化学工程
·
纳米材料合成
✓ 已验证
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
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2023
·
IF 5.2
Caixia Miao,Meng Liu,Shengdong Tan,Guikai Zhang,Shengqi Chu,Shaojia Song,Qiyang Zhang,Jiaju Yu,Guiyuan Jiang,Weiyu Song,Qian He,Wenhao Luo,Zhijie Wu
Zeolite-tailored bimetallic Pt-Sn catalysts have been shown to be effective for propane dehydrogenation (PDH). Here, we have successfully prepared and compared two Sn-Beta-supported bimetallic PtSn catalysts (Pt/Sn-Beta (DG) and Pt/Sn-Beta (DA)), in which the Sn-Beta zeolite was prepared by a dry-gel (DG) synthesis method involving in situ Sn incorporation or a post-synthesis method involving dealumination and Sn incorporation (DA), respectively. The as-prepared Pt/Sn-Beta (DG), possessing a less fraction of extra-framework Sn species comparing to Pt/Sn-Beta (DA), shows a superior performance in terms of activity (TOF, 1.8 s -1 ), selectivity (99.0%) and stability (7360 min) at 550 °C using 40 kPa propane and 60 kPa nitrogen gas, reflecting one of the highest PDH performances for bimetallic Pt-Sn catalysts under similar conditions. By a combination of the state-of-the-art electron microscopy-based techniques and advanced spectroscopy techniques , we found that the proper Pt-Sn nano-alloying in Pt/Sn-Beta (DG), rather than Sn coverage on Pt species in Pt/Sn-Beta (DA) owing to the migration of excess extraframework Sn species, is essential for providing an enhanced PDH performance, as the active Pt species could be well isolated, accessed and stablized in Pt/Sn-Beta (DG) by alloying.
研究领域:
催化化学
·
材料科学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
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2025
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IF 8.2
Chen Liu,Jin Hu,Haichang Zhang,Jiaxin Wu,Chunsheng Shi,Biao Chen,Chunnian He,Naiqin Zhao
Poly(ethylene oxide) (PEO)-based solid polymer electrolytes (SPEs) demonstrate strong electrode adhesion and facile processability, making them promising candidates in all-solid-state lithium metal batteries (ASSLMBs). However, poor ionic conductivity, low Li+ transference number, and insufficient mechanical strength greatly limit their practical application. Zeolite, a porous ceramic material rich in active sites, shows significant potential as a filler in the PEO-based SPEs. In this study, we prepared heteroatomic Sn-Beta zeolite with high Lewis acid activity through a simple two-step postsynthesis process and explored the mechanism of action of metal acidic sites on Li+ dissociation and transport. The Lewis acidic metal sites in the Sn-Beta zeolite effectively weaken the coordination environment of Li+ by binding the O atoms in PEO via metal–oxygen bonds, facilitating the transfer of Li+ along the PEO polymer chains. Moreover, it can promote the dissociation of the lithium salt by anchoring TFSI– anions, resulting in the release of free Li+. The obtained SPE (PL-Sn-Beta) exhibits a high ionic conductivity of 1.40 × 10–3 S cm–1 at 60 °C and a Li+ transference number of up to 0.51. Furthermore, the ordered pore channels of the Sn-Beta zeolite provide uniform Li-ion transport pathways, facilitating homogeneous Li+ deposition. As a result, the lithium symmetric cell with PL-Sn-Beta demonstrates a stable lithium plating/stripping cycle performance for over 2200 h at 60 °C and 0.1 mA cm–2. Meanwhile, the initial discharge capacity of the Li/PL-Sn-Beta/LiFePO4 full cell reaches 145.6 mAh g–1 at 1 C and 60 °C, and the capacity retention rate is 81.5% after 500 cycles. This work provides theoretical insights into the mechanism of zeolite fillers in SPEs as well as new design concepts.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FUEL
·
2022
·
IF 8.035
Tianliang Lu,Xianfeng You,Yanlong Zong,Yongming Xu,Xiaomei Yang,Lipeng Zhou
Production of γ-valerolactone (GVL) from ethyl levulinate (EL) was studied by catalytic transfer hydrogenation (CTH) strategy under mild conditions. Hydrothermally synthesized Sn-Beta zeolites with high crystallinity show high catalytic activity and selectivity. With isopropanol as hydrogen source, 97.1 % GVL yield with 100 % selectivity was given under 110 °C. Crystallization time for synthesis of Sn-Beta showed great effect on the catalytic performance. Sn-Beta- x d catalysts with longer crystallization time (≥7 days) have high crystallinity and better catalytic performance. Firstly, longer crystallization time is necessary for the formation of large amount of Lewis acid sites which catalyze the conversion of EL to GVL. Secondly, high level of silanol groups in Sn-Beta has negative effect on the catalytic performance. High crystallinity means the amount of silanol groups in Sn-Beta- x d at a low level which is favorable for this CTH reaction. Meanwhile, this is why hydrothermally synthesized Sn-Beta shows higher catalytic activity than post-synthesized Sn-Beta in the conversion of EL to GVL. Furthermore, the catalyst was reusable.
研究领域:
化学工程
·
催化材料
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）