Journal of the Taiwan Institute of Chemical Engineers
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2014
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IF 2.637
Chuan-Jun Yue,Miao-Miao Gan,Li-Ping Gu,Ya-Feng Zhuang
Cu/ZSM-5 prepared by in situ impregnated reduction was used for the catalytic dehydration of glycerol under solvent-free conditions. The catalyst was characterized by X-ray diffraction (XRD, transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET), ammonia temperature programmed desorption (NH 3 -TPD), and thermogravimetry-differential scanning calorimetry (TG-DSC) analyses. Results showed that the nano-copper in Cu/ZSM-5 was evenly distributed onto the surface of ZSM-5 pores. Under the optimum conditions of the catalytic dehydration of glycerol, conversion was 92.1 wt.%. The selectivities of acrolein and acetol were 80.4 wt.% and 11.5 wt.%, respectively. Moreover, the low temperature favored for acetol selectivity. The synergic catalysis of Cu and ZSM-5 through the enol intermediate was responsible for the selectivity in the catalytic dehydration of glycerol.
研究领域:
化学工程
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催化科学
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DOI
高影响因子
CATALYSIS TODAY
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2021
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IF 6.766
Shan Liu,Zhiquan Yu,Yao Wang,Zhichao Sun,Yingya Liu,Chuan Shi,Anjie Wang
Catalytic dehydration of glycerol over solid catalysts provides a sustainable and economic route to producing acrolein. Unsupported MoP catalyst was prepared by temperature-programmed-reduction method and used for the gas-phase glycerol dehydration. The catalyst was characterized by means of XRD, SEM, TEM, NH 3 -TPD, Py-IR, XPS, TG-DSC, and N 2 adsorption-desorption. It is indicated that the acidic P OH and M oOH groups, which are usually associated with the weak or moderate strength of Brønsted acid sites, were presented on the surface of MoP. The effects of reaction temperature and carrier gas flow rate on glycerol conversion and acrolein selectivity were investigated over MoP. The selectivity to acrolein was up to 89.0 % and kept constant in a 50-h run at 240 °C. The gradual decrease of glycerol conversion might be related to the insoluble carbonaceous materials deposited on the catalyst surface.
研究领域:
催化化学
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材料科学
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可再生能源
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产品关联
DOI
高影响因子
CLAYS AND CLAY MINERALS
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2022
·Vol. 70
·期 3
·460-479
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IF 2.207
Yu Wei Hua,Zhu Bao,Tong Dong Shen,Deng Kai,Fu Chao Peng,Huang Tian Hao,Zhou Chun Hui
Montmorillonite (Mnt)-based solid acids have a wide range of applications in catalysis and adsorption of pollutants. For such solid acids, the acidic characteristic often plays a significant role in these applications. The objective of the current study was to examine the effects of H 3 PO 4 -activation and supporting WO 3 on the textural structure and surface acidic properties of Mnt. The Mnt-based solid acid materials were prepared by H 3 PO 4 treatment and an impregnation method with a solution of ammonium metatungstate (AMT) and were examined as catalysts in the dehydration of glycerol to acrolein. The catalysts were characterized by nitrogen adsorption-desorption, powder X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, scanning electronic microscopy (SEM), X-ray photoelectron spectroscopy (XPS), diffuse reflectance ultraviolet-visible (DR UV-Vis) spectroscopy, temperature programmed desorption of NH 3 (NH 3 -TPD), diffuse reflectance Fourier-transform infrared (DR FTIR) spectroscopy of adsorbed pyridine, and thermogravimetric (TG) analyses. The phosphoric acid treatment of Mnt created Brönsted and Lewis acid sites and led to increases in specific surface areas, porosity, and acidity. WO 3 species influenced total acidity, acid strength, the numbers of Brönsted and Lewis acid sites, and catalytic performances. A high turnover frequency (TOF) value (31.2 h −1 ) based on a maximal 60.7% yield of acrolein was reached. The correlation of acrolein yield with acidic properties indicated that the cooperative role of Brönsted and Lewis acid sites was beneficial to the formation of acrolein and a little coke deposition (<3.3 wt.%). This work provides a new idea for the design of solid acid catalysts with cooperative Brönsted and Lewis acidity for the dehydration of glycerol.
研究领域:
催化化学
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材料科学
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环境工程
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DOI
高影响因子
Journal of Cleaner Production
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2019
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IF 6.395
Jiaojiao Zhang,Zheng Li,Xiaojing Cui,Jinlong Li,Shiyu Jia,Yingxiong Wang,Hongliang Wang,Xianglin Hou,Tiansheng Deng
Chemical reactions with products of high reactivity generally suffer from low yields due to the severe side reactions. This is the case for the synthesis of acrolein from glycerol dehydration. To improve the yield of acrolein, fast removal of high reactive acrolein molecules from the reaction system is desirable but remains a major challenge, due to the high viscosity of glycerol. To tackle this problem, the Pickering emulsion was chosen as the reaction system in this work to accelerate the removal of acrolein. A water-in-oil Pickering emulsion was fabricated for the liquid phase dehydration of glycerol to acrolein, which exhibits twice yield of acrolein compared with the homogeneous system. The combination of the transfer experiments and IR analysis confirmed the drastic restrain of the side reactions between acrolein and glycerol, due to the intensified mass transfer of acrolein from the liquid phase by the larger microinterface of emulsion. Furthermore, the transfer rate of acrolein through the water-oil interface can be tuned via a shift in the interfacial properties of the silica emulsifier by silylation treatment. The highest acrolein yield of nearly 50% was obtained with the highest transfer rate of acrolein on the silica silylated by (MeO) 3 Si(CH 2 ) 11 CH 3 .
研究领域:
化学工程
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界面科学
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催化反应
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产品关联
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
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2023
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IF 5.5
Hongrui Zhang,Feipeng Bao,Qiuwen Liu,Xin Yang,Huimin Chai,Kaijie Liu,Yibo Zhang,Xiangguang Yang
Catalytic vapor-phase dehydration of glycerol is an energy-efficient and environmentally friendly route for producing acrolein, a valuable organic chemical intermediate. However, anti-coking is one of the key problems due to the excessively acid catalytic sites and sluggish mass transfer, restricting the industrial application of this reaction. Herein, potassium element modified BPO 4 monolithic foams with the hierarchically porous structure were synthesized by adding potassium element in the gel precursor of BPO 4 . The catalyst introducing 3% K exhibited the best acrolein selectivity of 81.0% with nearly complete glycerol conversion. In a 10-hour run of the reaction at 320 °C, the selectivity of acrolein could remain at 75.9% with 94.5% glycerol conversion, indicating the superior stability. The excellent activity and stability for 3% K-BPO 4 is mainly attributed to the synergetic effect between hierarchical structure providing favorable mass transfer and appropriate acid catalytic sites inhibiting over dehydration reaction. They not only boost activity but also reduce coking, providing a unique approach for the design of solid acid catalyst.
研究领域:
催化化学
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材料科学
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能源化学
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产品关联
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2022
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IF 5.895
Ya’nan Shi,Rongshan Li,Jie Zheng,Yubin Xue,Yong Tao,Bo Yu
Bio-based propionate attracts increasing attention owing to its green nature and specific food additive market. To date, the time-consuming and costly fermentation process by strict anaerobes makes propionate production not ideal. In this study, we designed a new route for propionate production, in which 1,2-propanediol was first dehydrated to propionaldehyde and then to propionate by taking advantage of the robust oxidization capacity of the Pseudomonas putida KT2440 strain. The high atom economy (0.97 g/g) in this proposed pathway is more advantageous than the previous l-threonine-derived route (0.62 g/g). The molecular mechanism of the extraordinary oxidation capacity of P. putida KT2440 was first deciphered. The propionate production was realized in P. putida KT2440 by screening suitable glycerol dehydratases and optimizing the expression to eliminate the formation of 1-propanol and the accumulation of the intermediate propionaldehyde. The engineered strain produced propionate with a molar conversion rate of >99% from 1,2-propanediol. A high titer of 46.5 g/L pure propionic acid with a productivity of 1.55 g/L/h and a mass yield of 0.96 g/g was achieved in fed-batch biotransformation. Thus, this study provides another idea for the production of high-purity bio-based propionate from renewable materials with high atom economy.
研究领域:
生物技术
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微生物学
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化学工程
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代谢工程
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）