Catalysts
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2022
·Vol. 12
·期 1
·104
·
IF 4.501
Ying Duan,Qianqian Luo,Renfeng Nie,Jianshe Wang,Yongsheng Zhang,Tianliang Lu,Chunbao Xu
The production of methyl lactate as a degradable polymer monomer from biomass was an important topic for a sustainable society. In this manuscript, glycerol was oxidated to methyl lactate catalyzed by the combination of Au-CuO and Sn-Beta. The influence of Sn content, Sn source, and the preparation conditions for Sn-β was studied. The Au content in Au/CuO was also investigated by varying the Au content in Au/CuO. The catalysts were characterized by XRD, FTIR spectroscopy of pyridine adsorption, and TEM to study the role of Sn and the influence of different parameters for catalyst preparation. After the optimization of reaction parameters, the yield of methyl lactate from glycerol reached 59% at 363 K after reacting in 1.6 MPa of O2for 6 h.Keywords:glycerol;oxidation;methyl lactate;Sn-Beta;Au/CuO
研究领域:
催化化学
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生物质转化
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可持续化学
✓ 已验证
产品关联
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
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2022
·
IF 5.876
Shuang Wang,Lipeng Zhou,Beibei Gao,Yunlai Su,Xiaomei Yang
Sn-Beta is a good solid Lewis acid catalyst. Seed-assisted hydrothermal synthesis is a popular method for its preparation. However, the mechanism of seeds in the crystallization process is not clear. Here, the role of seeds in the growth of crystal and the influence on the properties of the corresponding products were studied. The seeds and gel was characterized by XRD , SEM, FT-IR and TG. During the crystallization, it was observed that the seeds were partially dissolved and formed seed fragments in the initial stage. Then the seed fragments acted as the core of the crystals and promoted the crystallization process. Seeds greatly decreased the crystal size of the products as compared with the direct hydrothermal method in absence of seeds. The acidity and catalytic performance of Sn-Beta synthesized via seeds route are similar with those of none-seeds method.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
MOLECULES
·
2025
·Vol. 30
·期 7
·1457
·
IF 4.6
Fenfen Guo,Yuxuan Wang,Zhicheng Jiang,Youjing Tu,Ruikai Li,Xingyu Zhang,Aoyi Tang,Yuan Liang,Lishi Yan,Hu Luo,Shenggang Li,Lingzhao Kong
The catalytic production of lactic acid from carbohydrates was considered a green way to efficiently utilize renewable biomass resources. In this study, an easy post-synthesis method was used to prepare a Sn-Beta catalyst for the production of lactic acid from glucose at 180 °C, 2 MPa, and 30 min. With optimized reaction time, temperature, pressure, and the ratio of raw material to catalyst, the yield of lactic acid reached an astonishingly high level of 76.0%. In addition, the catalyst characterizations were performed in-depth, revealing the intrinsic relationship between catalyst performance and structure, proving that the 2 wt% Sn was uniformly dispersed in the skeleton of Beta zeolite, which significantly increased the density of Lewis acid. Thus, the enhanced isomerization and retro-aldol condensation processes over the Lewis acid sites led to the high yield of lactic acid. This catalytic system kept stable after five cycles at mild conditions, showing high potential for industrial biomass utilization.
研究领域:
生物化学
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催化化学
✓ 已验证
产品关联
DOI
PubMed
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
MICROPOROUS AND MESOPOROUS MATERIALS
·
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
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材料科学
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
·
2019
·Vol. 95
·期 3
·798-805
·
IF 2.659
Dan Luo,Shengnan Liu,Wang Yin,Shuqian Xia
BACKGROUND Fast pyrolysis of lignocellulosics has provided an abundant sugar source for production of value-added chemicals, and levoglucosan is the most representative sugar in pyrolysis liquid (bio oil). This paper explored the potential for producing methyl lactate from levoglucosan by employing the mixed catalysts of zeolite tin beta (Sn-Beta) and zeolite hydrogen beta (H-Beta). RESULTS Under the optimal conditions (at 200 °C and mixed catalysts with H-Beta:Sn-Beta ratio of 1:5), the yield of methyl lactate obtained from levoglucosan conversion was as high as 35%. And the yield was comparable to that of methyl lactate obtained from glucose conversion under the similar conditions (at 200 °C and pure Sn-Beta). In order to investigate the reason, a contrasting experiment with glucose as substrate also was carried out with the mixed catalysts. The results indicated that during the levoglucosan conversion process, ‘the methanolysis of levoglucosan’ was likely to compete with ‘the dehydration of glucose’ for the Brønsted acid sites of H-Beta. In addition, the catalytic functions of H-Beta and Sn-Beta, and the reaction pathway were deeply investigated through tracking and comparing the conversion of levoglucosan over mixed H-Beta/Sn-Beta and over pure Sn-Beta catalysts, respectively. CONCLUSION The appropriately lower ratio of H-Beta:Sn-Beta and relatively higher temperature were favorable for the reaction. H-Beta containing Brønsted acid could remarkably accelerate the conversion of levoglucosan and methyl-glucosides to glucose. Sn-Beta containing Lewis acid mainly promoted the retro-aldol condensation of glucose and formation of methyl lactate. © 2019 Society of Chemical Industry
研究领域:
化学工程
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生物质能
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催化化学
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DOI
高影响因子
JOURNAL OF POROUS MATERIALS
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2021
·Vol. 28
·期 5
·1315-1324
·
IF 2.496
Cai Qiang,Yue Xiaoyang,Dong Wen-Sheng
Bimetallic modified Fe–Sn/Beta was synthesized and examined as a solid acid catalyst for the transformation of glucose into methyl lactate in methanol. The catalysts were characterized by a combined characterization techniques i.e. X-ray fluorescence spectroscopy, N 2 physisorption, powder X-ray diffraction, X-ray photoelectron spectroscopy, NH 3 temperature-programmed desorption, and pyridine adsorption Fourier transform infrared spectroscopy. A high yield of methyl lactate of 67% was achieved upon conversion of 0.3 g glucose in 24 g methanol over 0.15 g catalyst at 220 ℃ under 2 MPa N 2 for 6 h. The recyclability of the catalyst was also investigated, and the conversion of glucose remained constant; conversely, the yield of methyl lactate decreased slightly in five catalytic runs. The excellent catalytic performance of Fe–Sn/Beta was attributed to the presence of large amounts of Lewis acid sites. Besides, the rich mesoporosity in Fe–Sn/Beta improved mass transfer rates in the conversion of glucose to alkyl lactates.
研究领域:
催化化学
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能源化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Biobased Materials and Bioenergy
·
2017
·Vol. 11
·期 6
·562-567
·
IF 0.975
Wang Lan-Ying,Zhuang Jun-Ping,Yu Kai-Rong,Wu Shu-Bin
Sn-Beta zeolite is a promising catalysts for isomerization of glucose to fructose, which is a key step in the conversion of biomass to various platform chemicals. Herein, Sn-Beta-H zeolite was efficiently prepared via hydrothermal synthesis by using Al-Beta. Finally, the product was
heated to 423 K for 48 h then calcined at 550 °C for 6 h to obtain Sn-Beta-H sample. The results of XRD patterns confirmed that the prepared catalyst had both microporous and mesoporous; N2 sorption isotherms showed that the main pore size centered at around 3.5 nm; TD-DTG revealed
that the Sn-Beta-H zeolite had good thermal stability with the peaks on the DTG curves was 283 °C; FTIR and UV-Vis spectra also successfully indicated that tin substitution into the zeolite framework. The effects of various reaction conditions including reaction temperature, reaction time
and the amount of catalyst on glucose conversion and fructose yield and selectivity were investigated. Under optimized operating conditions, 10% glucose solution in 40 ml water, catalyst (4 g), at 120 °C for 2 h, resulting in fructose yield of 30.8% and selectivity of 61.3%. Moreover,
Sn-Beta-H zeolite could be easily recovered and efficiently reused without significant loss in its catalytic activity.
研究领域:
催化化学
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生物质转化
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材料科学
✓ 已验证
DOI
高影响因子
CELLULOSE
·
2019
·Vol. 26
·期 17
·9135-9147
·
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
·
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
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2017
·
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
·
可再生资源转化
✓ 已验证
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2021
·
IF 7.963
Meng Xia,Zheng Shen,Minyan Gu,Wenbo Chen,Wenjie Dong,Yalei Zhang
Microalgae residue was efficiently converted into lactic acid with a high yield (33.9%) under mild reaction conditions (210 °C, 2 h) over a Fe-Sn-Beta catalyst. Under the action of homogeneous H 3 O + and distinct Lewis acid sites on the catalyst, the production of lactic acid from microalgae residue underwent three main reaction steps: hydrolysis, isomerization , and retro-aldol condensation. Results demonstrated that the lipid component had a strong inhibitory effect on the production of lactic acid due to the formation of aromatics, esters, and complex nitrogenous heterocyclic compounds , which covered or poisoned the Lewis acid sites of the catalyst. The protein component acted as a chemical buffer that enhanced the production of lactic acid by controlling the release of monosaccharides from the carbohydrate fraction of microalgae and maintaining the catalytic activity of the catalyst. Thus, microalgae residue demonstrated great promise for the production of value-added chemicals.
研究领域:
生物化学
·
催化化学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）