ACS Omega
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2018
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IF 0
Changhui Zhu,Qiying Liu,Dan Li,Haiyong Wang,Caihong Zhang,Chunhua Cui,Lungang Chen,Chiliu Cai,Longlong Ma
Crystal α-zirconium phosphate (α-ZrP) was prepared by a hydrothermal method and exfoliated into a layered structure by n-hexylamine (C6H13NH2). Ni-based catalyst (Ni/ZrP) was promoted by loading nickel on the layered α-ZrP via ion exchange. The catalyst was performed to catalyze hydrodeoxygenation of 5-hydroxymethylfurfural (HMF) to 2,5-dimethylfuran (DMF), and a 68.1% yield of DMF and 100% conversion of HMF were achieved at 240 °C, 5 MPa H2, and 20 h. The DMF yield can still retain 52.8% after five cycles. The characteristics of the catalyst were investigated via N2 adsorption–desorption, X-ray diffraction, field emission scanning electron microscopy, high-resolution transmission electron microscopy, pyridine-adsorbed Fourier transform infrared (FTIR) spectra, FTIR spectra, inductively coupled plasma mass spectrometry, and thermogravimetric analysis–mass spectrometry, as well as Raman spectroscopy. A pathway from HMF to DMF was found with MF as the intermediate product, and DMF production was preferable via the −CH2OH group hydrogenolysis of HMF over Lewis acidic sites of Ni/ZrP, which is caused by the zirconium vacant orbits.
研究领域:
化学工程
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催化
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材料科学
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DOI
PubMed
ENERGY & FUELS
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2021
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IF 3.605
Chunli Li,Mingxia Zhang,Hao Li,Yahui Zhang
As an inevitable harmful waste, biomass tar has always been considered as one of the challenges of biomass resource utilization. In this paper, biomass tar is used as the carbon source for the preparation of biocarbon with different activators in one pot. The Pd@biocarbon catalysts with low Pd loading were synthesized for hydrodeoxygenation (HDO) of vanillin in the presence of poly(methylhydrosiloxane) (PMHS) as the hydrogen donor, avoiding gaseous hydrogen and high temperature. The effects of different activators (KOH and K2FeO4) and carbonization temperature on the structure and catalytic performance of the as-prepared Pd@biocarbon catalysts were investigated in detail. The characterization results showed that Pd@BC-KFe-800 activated by K2FeO4 and carbonized at 800 °C had abundant surface acid groups and a high degree of graphitization. Further evaluation of the catalytic activity showed that Pd@BC-KFe-800 had the highest catalytic activity and can achieve 94.6% vanillin conversion at 65 °C for 2 h. The mechanism study indicated that the high HDO activity is attributed to the synergistic effect of the active metal Pd and biocarbon with surface acidic hydroxyl groups and the good graphitization structure. Compared with KOH, K2FeO4 can improve the graphitization degree of biocarbon and lead to catalysts with stronger acidity, providing more acid sites for the HDO of vanillin. Furthermore, the as-prepared Pd@BC-KFe-800 catalyst has shown favorable recyclability after four uses. These findings not only provide a new idea for the green treatment of waste biomass tar but also give a reference value for the HDO of bio-oil under mild conditions.
研究领域:
化学工程
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材料科学
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环境科学
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催化
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生物化工
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DOI
高影响因子
GREEN CHEMISTRY
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2019
·Vol. 21
·期 10
·2709-2719
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IF 9.405
Hao Tang,Ning Li,Guangyi Li,Aiqin Wang,Yu Cong,Guoliang Xu,Xiaodong Wang,Tao Zhang
For the first time, gasoline and jet fuel range C7–C8 cycloalkanes and aromatics were selectively synthesized by the alcoholysis of poly(ethylene terephthalate) (PET) waste, followed by solvent-free hydrogenation and hydrodeoxygenation (HDO). It was found that methanol is highly reactive for the alcoholysis of PET waste. In the absence of any catalyst, a high yield of dimethyl terephthalate (97.3%) was achieved under mild conditions (473 K, 3.5 h). Dimethyl terephthalate exists as a solid and can be automatically separated from methanol with a decrease in temperature. Subsequently, dimethyl terephthalate was liquefied to dimethyl cyclohexane-1,4-dicarboxylate by hydrogenation over noble metal catalysts. Among the investigated catalysts, Pt/C exhibited the highest activity. Finally, the dimethyl cyclohexane-1,4-dicarboxylate as obtained was further hydrodeoxygenated to C7–C8 cycloalkanes and aromatics that can be used as gasoline or additives to improve the densities (or volumetric heat value) and sealabilities of current bio-jet fuels. Bimetallic Ru–Cu/SiO2 was found to be a promising HDO catalyst. According to the characterization results, the excellent HDO performance of Ru–Cu/SiO2 can be explained by the formation of smaller Ru–Cu alloy particles during the catalyst preparation. In real applications, dimethyl cyclohexane-1,4-dicarboxylate can also be simultaneously hydrodeoxygenated with biomass derived oxygenates to produce jet fuel with a suitable content of cycloalkanes and aromatics.
研究领域:
化学工程
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材料科学
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环境科学
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能源
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DOI
高影响因子
ACS Sustainable Chemistry & Engineering
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2021
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IF 8.198
Xiangchen Kong,Chao Liu,Yuyang Fan,Weicong Xu,Rui Xiao
Production of jet fuel precursors from waste kraft lignin through a depolymerization and hydrodeoxygenation (DHDO) method with a complex copper acid catalyst is reported. The kraft lignin undergoes a high degree of depolymerization, deoxygenation, hydrogenation, and C–C coupling. Monomers and dimers with molecular weights in the ranges of <200 Da and 354–452 Da are obtained with optimized yields reaching 93.29 and 39.30 C% at 360 °C for 8 h, while trimers and oligomers with higher molecular weights are also generated with lower contents. The high carbon yields of monomers and dimers are given by the incorporation of methanol solvent. The double bond equivalent (DBE) and polydispersity index (PDI) decrease from 14.77 and 2.77 in kraft lignin to 9.05 and 1.35 in the products, while the high heating value (HHV) increases from 24.53 to 36.47 MJ/kg after reaction. Furthermore, over 45% of the optimized products have boiling points in the range of that of commercial jet fuel (60–280 °C). All these results demonstrate the appropriate properties of the products from kraft lignin DHDO as potential jet fuel precursors.
研究领域:
化学工程
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催化
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可再生能源
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生物燃料
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产品关联
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
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2021
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IF 7.033
Xiangchen Kong,Chao Liu,Weicong Xu,Yue Han,Yuyang Fan,Ming Lei,Ming Li,Rui Xiao
Stubborn lignin (SL) is the thermochemically stable fragment generated from biomass utilization (e.g., pyrolysis , hydrolysis, fermentation, pulping), which is comparatively difficult to be further depolymerized into value-added bio-products. The cleavage of the stubborn linkages within the structure of SL, such as C C, α -O-4, and 4-O-5 linkages, is the key for its valorization. Herein, we investigated the depolymerization of SL through catalytic hydroprocessing in supercritical methanol with Cu/CuMgAlO x catalyst. The yield of monomers reached 37.76C% with 240 min at 300 °C. Cyclohexanols were identified as the major monomeric products, indicating the occurrence of hydrodeoxygenation and hydrogenation. GPC , quantitative 13 C NMR, HSQC NMR, and HMBC NMR analyses evidenced the depolymerization of SL and upgrading of its derivatives. Furthermore, the mechanistic studies were carried out to provide insights to the stubborn linkage cleavages. The degrees of difficulty to break up the three involved linkages obeyed the sequence of β -5 > 4-O-5 > α -O-4. The apparent activating energies ( E a ), chemisorption energies ( E c ), and bond dissociation energies (BDE) were determined computationally to support the experimental results from the perspectives of kinetics, chemisorption, and thermodynamics, respectively. This research provides a reliable way for the utilization of SL.
研究领域:
化学工程
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催化
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生物化学
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可再生能源
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）