JOURNAL OF POROUS MATERIALS
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2022
·Vol. 29
·期 6
·1873-1882
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IF 2.523
Song Wenjing,Cai Wenqing,Hu Shihua,Jiang Xingmao,Lai Weikun
Cu–CeO 2 /C composite catalysts with porous structure were prepared by a microwave-assisted carbonization–impregnation method, which demonstrated a significant performance enhancement for the selective hydrogenation of ethylene carbonate. It was shown by XRD, BET, SEM, TEM, XPS and H 2 -TPR that Cu–CeO 2 /C catalysts with appropriate copper-ceria interactions improving the dispersion of copper particles and providing a higher ratio of Cu + /(Cu + + Cu 0 ) and more oxygen vacancies on the surface. These interactions resulted in an enhanced adsorption of ethylene carbonate and a high hydrogenation activity. The effect of significant operating conditions such as reaction temperature, H 2 pressure and substrate ratio on the EC hydrogenation activity over the Cu–CeO 2 /C catalyst was also investigated to predict the optimal conditions to achieve maximum activity in this process.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
·
2020
·
IF 3.687
Na Ji,Zhenyu Liu,Xinyong Diao,Jinrong Bao,Zhihao Yu,Chunfeng Song,Qingling Liu,Degang Ma,Xuebin Lu
GVL (γ-valerolactone) is identified as an important biomass platform molecule due to its wide application. In this work, a series of novel supported Ni catalysts with different supports and Ni loading were synthesized via metal-organic chemical vapor deposition (MOCVD) method for the hydrogenation of EL (ethyl levulinate) to GVL. Fourier transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), nitrogen adsorption/desorption, inductively coupled plasma optical emission spectroscopy (ICP-OES) and transmission electron microscopy (TEM) were used to characterize the as-synthesized catalysts. The results showed that the 2 wt.% Ni/AC(MOCVD) presented superior catalytic activity when compared with the catalyst prepared by impregnation method. This behavior is explained in terms of the smaller Ni nanoparticles (4.28 nm) and higher dispersion on 2 wt.% Ni/AC(MOCVD). Among the catalysts, the 2 wt.% Ni/AC catalyst exhibited the best catalytic performance with 99.7 % EL conversion and 79.8 % GVL yield under 1 MPa initial H 2 pressure (measured at room temperature) at 250 °C for 2 h. In addition, the reaction conditions were optimized and the stability of the catalyst were also investigated. The insights gained from this study in the design of high dispersed Ni particles with smaller particle size via MOCVD method will facilitate the metal-catalyzed hydrogenation of EL to GVL.
研究领域:
化学工程
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生物质能源
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催化科学
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2021
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IF 8.198
Yaqi Yao,Xiaoqian Wu,Bo Chen,Zhiyu Tu,Oliver Y. Gutiérrez,Ying Cui,Jie Wang,Jiacheng Huang,Yan Xu,Han Sun,Haijun Chen,Zhenxin Yan,Donghai Mei,Yujun Zhao,Johannes A. Lercher
Hydrogenation of aliphatic esters to natural alcohols is an important strategy for the efficient utilization of biomass-derived oils. The synthesis of highly active copper (Cu)-based catalysts is a challenge for condensed-phase ester hydrogenation due to the difficulties in controlling active sites and catalyst deactivation. Here, a copper-based catalyst confined in a carbon nanocage reactor was successfully designed and prepared. The copper catalyst with 56 wt % SiO2 exhibited the best performance because of the optimum proportion of Cu+ and Cu0 sites and high dispersion. The interaction between SiO2 and Cu particles contributes to the formation of Cu+ species, which is the key site for the adsorption of carbonyl groups. Meanwhile, the confinement effect of the carbon nanocages effectively inhibited the agglomeration of the copper particles. The catalysts exhibited not only excellent thermal stability but also superior methanol resistance in comparison with the Cu/SiO2 catalyst. On the basis of the density functional theory (DFT) calculations results, methanol resistance should be attributed to the fewer hydroxyl groups on the catalyst surface, which increase the activation barrier for the dissociation of silica, allowing the stable holding of the copper species in the methanol solvent.
研究领域:
材料科学
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催化化学
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生物质能利用
✓ 已验证
产品关联
DOI
高影响因子
iScience
·
2022
·
IF 6.107
Tongyang Song,Yuanyuan Qi,Chen Zhao,Peng Wu,Xiaohong Li
Summary An ultrastable and efficient Cu@C/SiO 2 nanocatalyst was fabricated for the hydrogenation of ethylene carbonate, in which Cu nanoparticles are encapsulated by sorbitol-derived graphitized carbon overlayers. During the calcination of Cu-sorbitol/SiO 2 precursors under N 2 atmosphere, sorbitol decomposed to CO and CO 2 . The in situ generated CO not only reduced Cu 2+ to Cu 0 /Cu + , but also formed graphitized carbon overlayers on the Cu surface via the disproportionation of CO. The Cu@C/SiO 2 catalyst exhibited superior catalytic performance (91% MeOH yield and 43.6 h −1 TOF) at a H 2 /EC molar ratio of 20. Of particular note, the Cu@C/SiO 2 catalyst showed remarkable long-term stability during 736 h time-on-stream test without any deactivation. The graphitized carbon overlayers on the surface of Cu nanoparticles not only functioned synergistically with the surface Cu 0 /Cu + sites to promote the EC hydrogenation but also suppressed the sintering of Cu nanoparticles. Furthermore, the interaction of Cu nanoparticles and graphitized carbon overlayers stabilized the surface Cu + /(Cu 0 +Cu + ) ratio.
研究领域:
材料科学
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化学工程
✓ 已验证
DOI
PubMed
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 37
·29040-29047
·
IF 3.84
Bin Wang,Chao Wen,Yuanyuan Cui,Xi Chen,Yu Dong,Wei-Lin Dai
A series of Cu-based TiO2-supported catalysts were synthesized via facile ammonia evaporation for the selective hydrogenation of dimethyl oxalate (DMO) to ethylene glycol (EG). A 100% conversion of DMO, 99% selectivity for EG, and super stability were achieved over the 20% Cu/P25 TiO2 catalyst. The effect of the crystal phase of the titania support and the interaction between Cu and P25 were investigated. The active copper species located at the interface between the anatase and rutile phases play important roles in the selective hydrogenation. The excellent catalytic performance was mainly attributed to better copper dispersion and an appropriate ratio of Cu0/Cu+, which stems from the intimate interaction between Cu and the P25 support.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2025
·
IF 4.3
Lijie Wang,Tiantian Xiao,Heng Ma,Shitong Zeng,Zhihuan Qiu,Maoshuai Li,Yue Wang,Xinbin Ma
The selective hydrogenation of syngas-derived dimethyl oxalate (DMO) to methyl glycolate (MG) is an attracting downstream route for clean coal conversion. Developing efficient non-noble metal catalysts remains a significant challenge due to the tendency for over-hydrogenation. Herein, we prepared a series of atomically dispersed copper catalysts supported on Si 3 N 4 , oxidized silicon nitride (Si 3 N 4 @SiO 2 ), and SiO 2 to explore the chemical environment effect on catalytic performance. The Cu/Si 3 N 4 exhibited 89 % DMO conversion and 86 % MG selectivity, of which MG yield is threefold of that over the Cu/SiO 2 . Combined with various characterizations and density functional theory calculation, it is revealed that electron-deficient copper on the nitrogen-rich surface of Si 3 N 4 promoted hydrogen dissociation and this chemical environment greatly facilitated MG desorption, thus preventing the over-hydrogenation and improving the MG selectivity. This study highlights the pivotal role of chemical environment in optimizing the performance of copper-based catalyst for selective hydrogenation of symmetric-structured esters.
研究领域:
化学工程
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催化材料
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理论计算
✓ 已验证
DOI
高影响因子
RESEARCH ON CHEMICAL INTERMEDIATES
·
2024
·Vol. 50
·期 7
·3369-3389
·
IF 2.8
Wang Lu,Rehman Mooeez ur,Jiang Yong,Sun Fan,Zhao Yuanqi,Lu Xiyue,Zhang Zhijun,Liu Wei,Xu Yan,Zhai Yong,Zhao Yujun
With the growing global demand for biodegradable plastics, the hydrogenation of dimethyl maleate (DMM) to produce 1,4-butanediol (BDO), raw materials for poly(butylene succinate), has become one of the hot spots in chemical industry. In this work, we synthesized a series of Cu@C/ZnO–S x catalysts by the method of sorbitol modification for the liquid-phase hydrogenation of DMM. The modification with appropriate sorbitol led to a decoration of carbon on catalyst surface, which improved the copper dispersion and Cu + /(Cu 0 + Cu + ) molar ratio in the Cu@C/ZnO–S 0.08 catalyst. The carbon decoration not only promoted the formation of more copper species having stronger interaction with ZnO, but also enhanced the absorption of ester on catalyst surface. These distinctive properties contributed to the high performance of the Cu@C/ZnO–S 0.08 catalyst in DMM hydrogenation, achieving an excellent BDO yield of 98.4% and superior reusability. The insights into the roles of sorbitol modification could give valuable guidance to the further design of high performance catalysts for esters hydrogenation. Graphical abstract
研究领域:
化学工程
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
·
2020
·
IF 7.888
Xuepeng Wang,Meng Chen,Xingkun Chen,Ronghe Lin,Hejun Zhu,Chuanqi Huang,Wenshao Yang,Yuan Tan,Saisai Wang,Zhongnan Du,Yunjie Ding
The development of robust catalysts for selective hydrogenation of dimethyl oxalate (DMO) is key for the expansion of ethylene glycol (EG) production from C1 and renewable feedstocks. Copper-based catalysts promoted with Cr are industrially used, but it is desirable to develop more environmentally-benign alternatives. Silica-supported copper-zinc bimetallic catalysts featuring intimate metal contact are designed and used to establish the structure-performance relationships through combining in-depth characterizations with steady-state catalytic testing. Our study highlights: i ) that the surface Cu 0 /Cu + ratio is a reliable catalytic descriptor that determines the activity and selectivity, and ii ) the importance of copper-zinc interface in stabilizing copper nanoparticles both under reduction and hydrogenation conditions. Controlled zinc doping allows fine tuning of these properties for the targeted reaction. Excellent performance has been achieved on the best-performing catalyst with >99.6% DMO conversion, >96.0% EG selectivity, and unprecedented stability of 800 h without catalyst deactivation, which represents a significant advance in the selective hydrogenations.
研究领域:
催化化学
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材料科学
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环境科学
✓ 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）