The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Yushuai Sang - One of the best experts on this subject based on the ideXlab platform.
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catalytic conversion of enzymatic hydrolysis lignin into Cycloalkanes over a gamma alumina supported nickel molybdenum alloy catalyst
Bioresource Technology, 2021Co-Authors: Qingfeng Liu, Yunfei Bai, Hong Chen, Mengmeng Chen, Yushuai SangAbstract:Abstract The efficient depolymerization and hydrodeoxygenation of enzymatic hydrolysis lignin are achieved in cyclohexane solvents over a gamma-alumina supported nickel molybdenum alloy catalyst in a single step. Under initial 3 MPa hydrogen at 320 °C, the highest overall cycloalkane yield of 104.4 mg/g enzymatic hydrolysis lignin with 44.4 wt% selectivity of ethyl-cyclohexane was obtained. The reaction atmosphere and temperature have significant effects on enzymatic hydrolysis lignin conversion, product type and distribution. The conversion of enzymatic hydrolysis lignin was also investigated over different nickel and molybdenum-based catalysts, and the gamma-alumina supported nickel molybdenum alloy catalyst exhibited the highest activity among those catalysts. To reveal the reaction pathways of alkylphenol hydrodeoxygenation, 4-ethylphenol was tested as a model compound. Complete conversion of 4-ethylphenol into Cycloalkanes was achieved. A two-step mechanism of 4-ethylphenol dihydroxylation – hydrogenation is proposed, in which the benzene ring saturation is deemed as the rate-determining step.
Qingfeng Liu - One of the best experts on this subject based on the ideXlab platform.
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catalytic conversion of enzymatic hydrolysis lignin into Cycloalkanes over a gamma alumina supported nickel molybdenum alloy catalyst
Bioresource Technology, 2021Co-Authors: Qingfeng Liu, Yunfei Bai, Hong Chen, Mengmeng Chen, Yushuai SangAbstract:Abstract The efficient depolymerization and hydrodeoxygenation of enzymatic hydrolysis lignin are achieved in cyclohexane solvents over a gamma-alumina supported nickel molybdenum alloy catalyst in a single step. Under initial 3 MPa hydrogen at 320 °C, the highest overall cycloalkane yield of 104.4 mg/g enzymatic hydrolysis lignin with 44.4 wt% selectivity of ethyl-cyclohexane was obtained. The reaction atmosphere and temperature have significant effects on enzymatic hydrolysis lignin conversion, product type and distribution. The conversion of enzymatic hydrolysis lignin was also investigated over different nickel and molybdenum-based catalysts, and the gamma-alumina supported nickel molybdenum alloy catalyst exhibited the highest activity among those catalysts. To reveal the reaction pathways of alkylphenol hydrodeoxygenation, 4-ethylphenol was tested as a model compound. Complete conversion of 4-ethylphenol into Cycloalkanes was achieved. A two-step mechanism of 4-ethylphenol dihydroxylation – hydrogenation is proposed, in which the benzene ring saturation is deemed as the rate-determining step.
Chenguang Wang - One of the best experts on this subject based on the ideXlab platform.
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synthesis of jet fuel range Cycloalkanes with cyclopentanone and furfural
Energy & Fuels, 2020Co-Authors: Qiang Liu, Qi Zhang, Qiying Liu, Xinghua Zhang, Chenguang WangAbstract:In this work, high density jet fuel range Cycloalkanes were synthesized in high yields (~80%) by solvent-free aldol condensation of cyclopentanone and furfural followed by hydrodeoxygenation (HDO)....
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production of renewable long chained Cycloalkanes from biomass derived furfurals and cyclic ketones
RSC Advances, 2018Co-Authors: Qiying Liu, Caihong Zhang, Ning Shi, Xinghua Zhang, Chenguang WangAbstract:Developing renewable long-chain Cycloalkanes from lignocellulosic biomass is of significance because it offers huge resource storage, wide applications in aviation/diesel fuels and mitigation of CO2 emissions. In this paper, Cycloalkanes with carbon chain lengths of 13–18 were produced from biomass-derived furfural species (furfural and 5-hydroxymethylfurfural) and cyclic ketones (cyclopentanone and cyclohexanone) via aldol condensation, followed by hydrogenation to saturate the CC and CO bonds, and hydrodeoxygenation to remove oxygen atoms. The aldol condensation of the furfural species with cyclic ketones was catalyzed by NaOH and the target condensation intermediates were obtained in yields of more than 90% at room temperature (30 °C) with a short reaction time (40 min). By using amorphous zirconium phosphate combined with Pd/C as the catalyst, liquid Cycloalkanes were produced at the optimal conditions with a yield of 76%. When the combined solid catalyst was reused, the target products reduced after the second run but the initial yield could be largely recovered by recalcination of the spent zirconium phosphate. Considering that cyclopentanone and cyclohexanone can be easily produced from furfural (originating from hemicellulose) and phenol (originating from lignin), respectively, this condensation has the potential to achieve the integrated conversion of biomass-derived cellulose, hemicellulose and lignin to jet fuel and/or diesel additives.
Tao Zhang - One of the best experts on this subject based on the ideXlab platform.
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synthesis of gasoline and jet fuel range Cycloalkanes and aromatics from poly ethylene terephthalate waste
Green Chemistry, 2019Co-Authors: Aiqin Wang, Yu Cong, Tao Zhang, Xiaodong Wang, Hao TangAbstract: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.
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Synthesis of jet fuel range Cycloalkanes with diacetone alcohol from lignocellulose
Green Chemistry, 2016Co-Authors: Fang Chen, Aiqin Wang, Yu Cong, Xiaodong Wang, Tao ZhangAbstract:Jet fuel range branched Cycloalkanes were first synthesized in high carbon yield (∼76%) with diacetone alcohol which can be derived from lignocellulose. These Cycloalkanes have a high density (0.83 g mL−1) and a low freezing point (216.5 K). As a potential application, they can be used as additives to conventional bio-jet fuels.
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synthesis of diesel or jet fuel range Cycloalkanes with 2 methylfuran and cyclopentanone from lignocellulose
Energy & Fuels, 2014Co-Authors: Xinkui Wang, Aiqin Wang, Yu Cong, Xiaodong Wang, Xueru Sheng, Tao ZhangAbstract:2-Methylfuran (2-MF) and cyclopentanone (CPO) are the selective hydrogenation products of furfural, which can be produced in industrial scale with lignocellulose. In this work, renewable diesel or jet fuel range branched alkanes and Cycloalkanes were first synthesized simultaneously by the solvent-free hydroxyalkylation/alkylation (HAA) of 2-MF and CPO followed by hydrodeoxygenation (HDO). Among the solid acid catalysts used in this work, Nafion-212 resin exhibited the best activity and selectivity for the HAA of 2-MF and CPO. The excellent performance of Nafion-212 resin can be attributed to the high acid strength of this catalyst. After the HDO of the HAA products of 2-MF and CPO over several nickel catalysts, a mixture of jet fuel range branched alkanes and Cycloalkanes with relatively higher density was obtained at high carbon yield. Compared with Ni/SiO2, acidic support loaded nickel catalysts are more active in the HDO process, which may be attributed to the promotion effect of acid sites in dehydra...
Thomas M Gilbert - One of the best experts on this subject based on the ideXlab platform.
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ab initio prediction of ring strain enthalpies of cyclic amine boranes
Tetrahedron Letters, 1998Co-Authors: Thomas M GilbertAbstract:Abstract Ring strain enthalpies for a series of cyclic amine-boranes (1-azonia-2-borataCycloalkanes) were calculated from MP4(SDTQ)/6-31G ∗ //MP2/6-31G ∗ energies by the group equivalent method. Small rings exhibit smaller RSEs than do the corresponding Cycloalkanes; larger rings exhibit RSEs essentially identical to those of the corresponding Cycloalkanes.
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ab initio prediction of ring strain enthalpies of cyclic amine boranes
Tetrahedron Letters, 1998Co-Authors: Thomas M GilbertAbstract:Abstract Ring strain enthalpies for a series of cyclic amine-boranes (1-azonia-2-borataCycloalkanes) were calculated from MP4(SDTQ)/6-31G ∗ //MP2/6-31G ∗ energies by the group equivalent method. Small rings exhibit smaller RSEs than do the corresponding Cycloalkanes; larger rings exhibit RSEs essentially identical to those of the corresponding Cycloalkanes.
