BIORESOURCE TECHNOLOGY
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2019
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IF 6.669
Jun Hu,Shenghua Zhang,Rui Xiao,Xiaoxiang Jiang,Yunjun Wang,Yahui Sun,Ping Lu
Using isopropanol as an in situ hydrogen donor, catalytic transfer hydrogenolysis of lignin into monomeric phenols was studied at mild conditions. The performance of catalysts and the effects of H 2 , temperature, and time on depolymerization of acid extracted birch lignin (ABL) were extensively examined. Platinum-rhenium supported on titanium dioxide (PtRe/TiO 2 ) exhibited much higher activity on disrupting C O bonds than Pd/C, HZSM-5, Pt/TiO 2 , and Re/TiO 2 . 18.71 wt% monophenols was achieved for depolymerization of ABL over PtRe/TiO 2 at 240 °C for 12 h with He. 4-Propylsyringol had the highest yield of 7.48 wt%. 2D HSQC NMR analysis reveals that β-O-4 bonds have been fully disrupted during depolymerization. Addition of H 2 led to less monophenols, likely due to the competitive adsorption of active sites on catalysts. Structure-reactivity analysis based on six representative lignins shows that the total yields of monophenols were highly linearly correlated with the β-O-4 contents (R 2 = 0.97).
研究领域:
化学工程
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可再生资源利用
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DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
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2020
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IF 5.006
Jingjie Luo,Enhui Qu,Yixue Zhou,Yanan Dong,Changhai Liang
Rhenium , although viewed as one of the noble metals with lower-price, has been commonly used as doping element in the bimetallic catalysts due to its middlebrow to activate hydrogen. Its major role as catalyst is less frequently mentioned. In this work, rhenium has been decorated on the surface of activated carbon and used for the selective hydrogenation of dimethyl 1, 4-cyclohexanedicarboxylate (DMCD) to 1, 4-cyclohexanedimethanol (CHDM). Characterizations suggested that ReO x particles were anchored occupying the surface oxygenated groups on pre-functionalized carbon. Rhenium decoration modified both the textural and chemical properties of the samples. Electrons were easily transferred from Re to the neighboring C atoms as a result of the formation of fine ReO x particles. Medium strong acid sites were generated and rhenium species in the reduced states could be still maintained under appropriate rhenium dispersion. The moderate hydrogenation ability of rhenium catalyst partially restrained the excessive hydrogenation of CHDM to other by-products. Rational decoration of 5 wt% Re performed the better catalytic performance with complete conversion of diester and 66 % yield of diol. The specific rate reached 9.5 × 10 2 m m o l D M C D ∙ g R e - 1 ∙ h - 1 at 220 °C under 10 MPa H 2 .
研究领域:
催化化学
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材料科学
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产品关联
DOI
高影响因子
RSC Advances
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2021
·Vol. 12
·期 1
·602-610
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IF 3.361
Yingxin Liu,Kai Liu,Meihua Zhang,Kaiyue Zhang,Jiao Ma,Shuwen Xiao,Zuojun Wei,Shuguang Deng
Highly active and thermally stable Cu–Re bimetallic catalysts supported on TiO2 with 2.0 wt% loading of Cu were prepared via an incipient wetness impregnation method and were applied for liquid phase selective hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL) in H2. The effect of the molar ratios of Cu : Re on the physico-chemical properties and the catalytic performance of the Cu–Re/TiO2 catalysts was investigated. Moreover, the influence of various reaction parameters on the hydrogenation of LA to GVL was studied. The results showed that the Cu–Re/TiO2 catalyst with a 1 : 1 molar ratio of Cu to Re (Cu–Re(1 : 1)/TiO2) exhibited the highest performance for the reaction. Complete conversion of LA with a 100% yield of GVL was achieved in 1,4-dioxane solvent under the reaction conditions of 180 °C, 4.0 MPa H2 for 4 h, and the catalyst could be reused at least 6 times with only a slight loss of activity. Combined with the characterization results, the high performance of the catalyst was mainly attributed to the well-dispersed Cu–Re nanoparticles with a very fine average size (ca. 0.69 nm) and the co-presence of Cu–Re bimetal and ReOx on the catalyst surface.
研究领域:
催化化学
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可再生能源
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材料科学
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产品关联
DOI
PubMed
高影响因子
ACS Applied Nano Materials
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2025
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IF 5.5
Weitao Mao,Yangjian Sun,Mingjie Liu,Xiaofeng Gao,Xiang Liu,Zongbi Bao,Qiwei Yang,Qilong Ren,Zhiguo Zhang
The development of cost-effective catalysts for mild arene hydrogenation is essential for the advancement of sustainable chemical processes. We present a rhenium-promoted nickel catalyst supported on hydroxyapatite (NiRe0.5/HAP) that enables efficient arene hydrogenation under mild conditions (50–130 °C, 0.5–2.0 MPa of H2). Using toluene hydrogenation as a model reaction, NiRe0.5/HAP (4.81 h–1 TOF) demonstrates nearly 13 and 30 times the catalytic activity of monometallic Ni/HAP (0.36 h–1 TOF) and Re/HAP (0.16 h–1 TOF), respectively, at 50 °C and 1.0 MPa of H2. Structural and mechanistic studies reveal a trifunctional role of Re: (1) geometrically isolates Ni sites, preventing sintering and forming a highly dispersed NiRe bimetallic species that enhances surface accessibility of metal active sites; (2) modulates the electronic properties of Ni via Ni-to-Re electron transfer, accelerating H2 dissociation and promoting hydrogenation; and (3) increases Lewis acidity, facilitating aromatic ring adsorption. The NiRe0.5/HAP catalyst exhibits broad substrate compatibility, efficiently hydrogenating functionalized aromatics and heterocycles in yields of up to 99%. Notably, it enables the complete hydrogenation of aromatic polyester polyethylene terephthalate (PET), yielding (bio)degradable polyethylene-1,4-cyclohexanedicarboxylate (PECHD), highlighting the robustness of this system. This work presents a synergistic electronic-geometric design strategy for non-noble bimetallic catalysts, delivering noble-metal-like performance with the cost advantages of transition metals for sustainable arene valorization.
研究领域:
催化化学
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材料科学
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绿色化学
✓ 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）