FUEL PROCESSING TECHNOLOGY
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2016
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IF 3.847
Chao Zhou,Xiangdong Zhu,Feng Qian,Wei Shen,Hualong Xu,Shicheng Zhang,Jianmin Chen
This work investigated the yields of monomeric phenols in bio-oil derived from hydrothermal liquefaction of rice straw (RS) in water and ethanol mixtures using a reductive CuZnAl catalyst. Based on the results of an initial analysis, five monomeric phenolic compounds were selected for research due to their higher concentrations, namely phenol, 4-ethyl-phenol, 2-methoxy-phenol, 2-methoxy-4-ethyl-phenol and 2,6-dimethoxy-phenol. The optimized conditions for the production of monomeric phenols can be determined as: 2 g of CuZnAl catalyst, a ratio of 50% ethanol/50% water (v/v), a temperature of 300 °C and a reaction time of 30 min. Results suggested that the maximum yield of total monomeric phenols could reach as high as ~ 26.8% (based on the mass of RS lignin), and that the aqueous phase yielded 95.5% of the monomeric phenols due to the solubilization of the ethanol. The CuZnAl catalyst was recycled five times, and a slight loss in activity was observed and examined using a number of technologies, including inductively coupled plasma , X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy and energy dispersive X-ray detection. The low-cost nature of the CuZnAl catalyst makes it an ideal catalyst for the enhancement of monomeric phenols yields in water and ethanol mixtures.
研究领域:
生物化学
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可再生能源
✓ 已验证
产品关联
DOI
高影响因子
AUSTRALIAN JOURNAL OF CHEMISTRY
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2019
·Vol. 72
·期 6
·417-424
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IF 1.226
Changna Gan,Yunhao Wang,Chenliang Ye,Cuili Guo,Changna Gan,Yunhao Wang,Chenliang Ye,Cuili Guo
A series of CuZnAl catalysts derived from layered double hydroxide precursors with different Cu/Zn molar ratios were synthesised by a co-precipitation method for methyl acetate hydrogenation. The best catalytic performance was obtained when the Cu/Zn molar ratio reached 0.25 : 1. After fixing the Cu/Zn molar ratio at 0.25 : 1, the effect of aging methods, including ultrasound, high shear mixer stirring, and magnetic stirring, were investigated, which showed that 0.25CuZnAl-u and 0.25CuZnAl-h exhibited a higher conversion and selectivity than that of 0.25CuZnAl-m, especially under low reaction temperatures. The physicochemical properties of the CuZnAl catalysts were characterised by X-ray diffraction, inductively coupled plasma–atomic emission spectroscopy, N2 physisorption, N2O chemisorption, transmission electron microscopy, H2-temperature-programmed reduction, X-ray photoelectron spectroscopy, and H2-temperature-programmed desorption. It was found that compared with 0.25CuZnAl-m, 0.25CuZnAl-u and 0.25CuZnAl-h possessed a stronger interaction between Cu and the support, smaller copper particle size, and higher copper dispersion, which improved the catalytic performance.
研究领域:
化学工程
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催化材料科学
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DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
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2022
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IF 8.129
Jing Liu,Yinzhao Jia,Sen Wang,Jinchuan Fan,Wei Huang
The impact of nanomaterial morphology on the structures of catalysts has drawn intense interest. Based on previous work, we discovered that ZnO plays an essential role in the ethanol production . In this research, we discussed the impact of ZnO with different morphology (rod-like, granular-like and flower-like) on the performance of CuZnAl slurry catalysts for the ethanol production. The catalytic performance was evaluated at H 2 /CO = 2, 250 °C and 4.0 MPa, and the catalyst structures were tested by XPS, in situ DRIFT and so on. The results show that CuZnAl catalysts prepared with rod-like and granular-like ZnO show the better selectivity of methanol and DME, which is assigned to the highly dispersion of Cu species and more quantity of acidic sites, respectively. CuZnAl catalyst prepared with flower-like ZnO possesses the higher total alcohol selectivity (45.0%) and the highest ethanol proportions in total alcohol (50.0%). Flower-like ZnO that exposed more polar (002) facets results in more surface defect structures (oxygen vacancy, Zn (2-δ) ) and high ratio of Cu 0 /Cu + in this catalyst, all of which are related to the formation of ethanol.
研究领域:
催化化学
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纳米材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF PHYSICS AND CHEMISTRY OF SOLIDS
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2022
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IF 4.383
Jingrong Wang,Zhihua Gao,Pengquan Yan,Yaxing Shen,Rui Yang,Zhijun Zuo,Wei Huang
CuO with a large microcrystalline differentiation was prepared by hydrothermal method , and the activity of the CuZnAl catalysts prepared by combining CuO with ZnAl was tested in the CO hydrogenation reaction. The effect of Cu species crystallite size on catalytic structure and performance was revealed. The experimental results show that CuO crystallite grow with the raising of hydrothermal temperature. When the hydrothermal temperature was 130 °C, CZA-130 exhibited the stable crystallite size of Cu species, high Cu/Zn molar ratio, and strong interaction between copper and zinc oxide, so the selectivity of total alcohol could reach up to 71.39%. Moreover, the ratio of C 2+ OH in the alcohol product is positively correlated with higher ratio of Cu + /Cu 0 and total number of alkalis, which are related to the ability of growing carbon chain.
研究领域:
化学工程
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催化科学
✓ 已验证
DOI
高影响因子
Molecular Catalysis
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2025
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IF 4.9
Lu Ren,Bin Wang,Yueli Wen,Maohong Fan,Zhaoxiong Huang,Wenxuan Li,Wei Huang,Jing Li,Jianping Guo
Acid-base synergistic effect is crucial in adjusting the catalytic performance of CO 2 hydrogenation to methanol, an efficient CO 2 emission reduction and carbon recycle strategy. Two MOFs-derived catalysts (CZ-MIL, CA-ZIF) with opposite acid-base properties were tailored by using MIL-68 (Al) and ZIF-8 (Zn) as precursors, and the above two MOFs precursors were hybridized (C-ZAx) to control the acid-base property of the catalyst. C-ZA0.6 (molar ratio of MIL-68 (Al) to ZIF-8 (Zn)=0.6) exhibits a promising catalytic performance with CO 2 conversion of 8.9 %, methanol selectivity of 61.85 %, and STY of 117.02 mg mL −1 ·h −1 at 4 MPa and 523 K. Combined with comprehensive analysis, it is found that methanol selectivity is closely related to weak acid sites arising from the residual skeleton of MIL-68. Acid-base synergy facilitates the hydrogenation of CO 2 to methanol. The basic sites are responsible for adsorbing and activating CO 2 , and the acidic site helps to stabilize CO* and facilitate the further hydrogenation to methanol. This work provides a new idea and feasible method for enhancing the catalytic performance of CO 2 hydrogenation to methanol.
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
Journal of the Taiwan Institute of Chemical Engineers
·
2023
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IF 5.7
Junchi Meng,Xingzhou Yuan,Yang Yan,Feng Zhou,Huixia Ma,Wenyu Long,Lei Zhang,Jian Zhang
Background Recently, with the emphasis on hydrogen as alternative clean energy, it is necessary to identify a safe and efficient technique. As a hydrogen storage technique, the liquid organic hydrogen carrier (LOHC) technique has the advantages of high hydrogen storage density, high safety, and low technical cost. Methods A series of Ni x /CuZnAl catalysts were synthesized using co-precipitation and ultrasonic-assisted incipient wetness impregnation methods. Combining XRF, XRD, Uv-vis, H 2 -TPR, XPS, TEM, and SEM techniques, we show the morphology of the active site during the reaction, and further explore the effects of the formation of the metal cluster NiCuZn. Significant findings The multi-metal oxide phase in the sample disappeared after reduction and was transformed into the metal cluster NiCuAl. During the formation of the metal cluster NiCuAl on the catalyst surface, electron transfer towards Ni occurred and the reduction temperature of Ni was lowered, which contributed to the electronic effect and synergy. In this work, The Ni 10 /CuZnAl catalyst shows the best dehydrogenation activity and selectivity, the catalytic effect was 15–20 times that of the CuZnAl catalyst, and the hydrogen evolution rate reached 77.31 ± 1.25 mmol/g cat /h. Moreover, based on the characterization analysis, the work speculates that the active atom H simultaneously dissociates and desorbs on the Cu and Ni surfaces of the metal cluster. In addition, as a possible active center, with a strong metal-support interaction, the metal cluster NiCuZn promotes the dehydrogenation reaction.
研究领域:
催化化学
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能源材料科学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2024
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IF 8.1
Kejing Wang,Yongjun Liu,Zhiwen Li,Nan Cui,Lei Sun,Wei Huang
The valence states of Cu site are regarded as an important factor affecting the performance of syngas to higher alcohols (C 2+ OH). Regrettably, the role of Cu 0 and Cu + in CO hydrogenation to higher alcohols remains controversial due to the complexity of the reaction. In this study, Cu 0 and Cu 2 O powders are directly added as the precursors to adjust the ratios of Cu + /(Cu 0 +Cu + ) and Cu particle sizes in CuZnAl catalysts by a complete liquid-phase (CLP) technology. The CAT-Cu 0 catalyst with higher Cu 0 content shows the highest CO conversion (>15%) ascribing to the biggest S Cu , but is also accompanied by the highest CO 2 selectivity (>40%), while the CAT-Cu + catalysts with higher Cu + content displays relative better C 2+ OH selectivity (>60%) and stability due to a higher probability of CO insertion. In-situ DRIFTS experiments reveal that a synergy between larger Cu particle sizes (30～40 nm) and surface Cu + sites, in which larger Cu sizes enhances the probability of bridge CO adsorption, thereby favoring the C–O bond dissociation for CH x formation. Meanwhile, Cu + active sites provide a higher probability for CO/CHO insertion to form CH 3 CHO*/CH 2 CO* intermediates. This study further deepens our understanding of the critical controlling factors for highly selective synthesis of C 2+ OH from syngas over Cu-based catalysts.
研究领域:
化学工程
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催化
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材料科学
✓ 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）