ACS Sustainable Chemistry & Engineering
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2017
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IF 5.951
Fufeng Cai,Xianghai Song,Yuanfeng Wu,Jun Zhang,Guomin Xiao
In this study, different acid-modified Co–Al catalysts were prepared and employed for glycerol hydrogenolysis by the addition of B, Ce, Zr, and heteropolyacids (HSiW, HPW, HPMo) to Co–Al catalysts. The catalysts prepared in this work were thoroughly examined by various characterization methods such as BET, ICP, SEM, H2 chemisorption, TEM, XRD, H2-TPR, NH3-TPD, XPS, and FTIR. The results showed an increase in the acid strength and Co dispersion on the catalytic surface for the modified Co–Al catalysts. This facilitated the conversion of glycerol. When ethanol was used as a solvent, the selectivity of 1,2-propanediol (1,2-PDO) by the acid-modified Co–Al catalysts decreased slightly, attributable to the enhanced etherification activity of glycerol with ethanol. However, when water was used as a solvent, the modified Co–Al catalyst with the B, Ce, and Zr species increased the selectivity of 1,2-PDO. Addition of heteropolyacids to the Co–Al catalyst enhanced the selectivity of 1,3-propanediol (1,3-PDO) as compared to 1,2-PDO selectivity which was relatively low due to its association with Brønsted acid sites on the modified Co–Al catalysts. The optimal HSiW/Co–Al catalyst (in terms of both 1,2- and 1,3-PDO selectivity) showed 76.3% glycerol conversion and 18.3% 1,3-PDO selectivity with a good stability. This could be attributed to the existence of well-dispersed Co particles with strong interaction between Co and W species.
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 Science & Technology
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2016
·Vol. 6
·期 14
·5656-5667
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IF 5.287
Fufeng Cai,Guomin Xiao
In this work, a series of Cu–Co–Al catalysts with different Ce loadings were applied to the hydrogenolysis of glycerol to 1,2-propanediol in a fixed-bed flow reactor. The physicochemical properties of the synthesized catalysts were analyzed using BET, N2O chemisorption, SEM, TEM, XRD, H2-TPR, NH3-TPD and XPS techniques. Systematic characterization demonstrated that the incorporation of Ce into the Cu–Co–Al catalyst could effectively restrain the aggregation of active metal species as well as the growth of metallic particles during calcination and reduction, which resulted in the formation of highly dispersed active metals. Large amounts and superior strength of acid sites were present in the Ce-promoted Cu–Co–Al catalysts, as confirmed by NH3-TPD analysis. The reducible nature of the Cu–Co–Al catalyst greatly increased after the addition of Ce. The higher concentration of acid sites, excellent reducibility and highly dispersed active metals were responsible for the superior catalytic activity of the 8Ce/Cu–Co–Al catalyst and it attained 91.6% glycerol conversion and 92.4% 1,2-propanediol selectivity. In addition, the effects of different process parameters such as the solvent, reaction temperature, operating pressure, catalyst loading, glycerol concentration and liquid flow rate on glycerol hydrogenolysis together with the catalyst stability were studied in detail, showing that the Ce-promoted Cu–Co–Al catalyst had high efficiency and stability for glycerol hydrogenolysis.
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
Molecular Catalysis
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2023
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IF 4.6
Zong-Pin Fu,Yun-Peng Zhao,Fa-Peng Wu,Jin-Xuan Xie,Le-Le Qiu,Jian Xiao,Jing Liang,Yong-Hui Bai,Fang-Jing Liu,Jing-Pei Cao
The selective hydrogenolysis of C O bonds is critical for the effective valorization of lignin. Herein, we synthesized a series of highly efficient Ni x Co y Al-T catalysts by a coprecipitation-calcination-reduction method and evaluated their catalytic hydrogenolysis performance towards the C O bonds of lignin-derived aryl ether, using isopropanol as the hydrogen donor source. The results revealed that the Ni 0.5 Co 1.5 Al-600 catalyst displayed superior activity and its catalytic performances were strongly influenced by the Ni/Co molar ratios and calcination temperatures. The enhanced dispersion of metal particles and the electron transfer from Ni to Co in Ni 0.5 Co 1.5 Al-600 catalyst facilitated the cleavage of C O bonds in lignin model compounds. Furthermore, the β-benzyl-H atom in 2-phenoxy-1-phenylethanol (PPE) also contributes to the cleavage of C aliphatic -O bonds. Under optimized reaction conditions (180 ℃, reaction time 2 h), PPE was completely converted over the Ni 0.5 Co 1.5 Al-600 catalyst, and the yield of ethylbenzene and cyclohexanol reached 95.91wt% and 85.73wt%, respectively. These findings demonstrate that the Ni x Co y Al-T catalytic system holds great promise for the production of valuable chemicals from lignin under mild conditions.
研究领域:
化学工程
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可再生资源转化
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产品关联
DOI
高影响因子