RSC Advances
·
2013
·Vol. 3
·期 31
·12635-12640
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IF 2.562
Yuxin Wang,Jinhu Wu,Shengnian Wang
The importance of the acidity and mesoporous structure to the hydrodeoxygenation activity of catalysts for bio-oil upgrading was investigated. By testing three model bio-oil compounds, we showed that catalysts with a strong acidity (e.g. ZSM-5) have a high hydrodeoxygenation activity, while the mesoporous structure of the support can further improve the catalytic performance of ZSM-5.
研究领域:
能源化学
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催化科学
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DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
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2024
·
IF 5.8
Shan Cheng,Yi Fu,Hong Tian,Yi Cheng,Jiawei Wang,Jiang Zhu,Linxi Guo,Xuan Huang
The selectivity and catalytic mechanism of HZSM-5 in the pyrolysis of lignin model compounds at 600 °C were investigated using Py-GC/MS and density functional theory (DFT). The findings indicate that HZSM-5 elevated the relative content of aromatic hydrocarbons in the pyrolysis products of phenol, vanillin, and syringol by 12.3 %, 11.7 %, and 7.5 %, respectively. Meanwhile, the relative content of oxygen-containing products, including aldehydes and acids, was reduced by 15.7–52.0 %. Throughout the pyrolysis of lignin model compounds, various side chain reactions take place, such as dissociation, decarbonylation, isomerization rearrangement, alkylation, and aromatization. The selective catalytic decomposition mechanism of HZSM-5 on oxygen-containing functional groups involves both the physical selection imparted by the pore size structure and the selection of acid sites that form hydrogen bonds with hydroxyl, carbonyl, and methoxy groups. This mechanism was corroborated by DFT calculations, which showed that the energy barriers for the removal of most oxygen-containing functional groups were lowered by 1.7–72.4 kJ/mol. These results provide an in-depth understanding of the catalytic pyrolysis of lignin and pave the way for future research on the high-value utilization of waste lignin.
研究领域:
生物质能
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催化化学
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环境科学
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产品关联
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2024
·
IF 5.6
Xialin Ji,Xiaoke Tian,Mengqing Zhou,Changzhou Chen,Jianchun Jiang
In this study, different kinds of lignin, including enzymatic hydrolysis of lignin (EHL), alkaline lignin (AL), kraft lignin (KL) and sodium lignosulfonate (LS) were investigated as precursor to prepare Ni@BTC@X (X= EHL, AL, KL, LS) catalysts using a traditional hydrothermal method with Ni-MOF for HDO upgrading of lignin derivative vanillin (VAN) to generate high value chemical 2-methoxy-4-methylphenol (MMP). The catalytic performance of these catalysts was investigated under different reaction conditions, and it was explored that the conversion of VAN was close to 100 % and the MMP yield was close to 90 % under the optimal conditions (Ni@BTC@LS catalyst, 220 ℃, 4 h, isopropanol, 2 MPa N 2 ). Various physical-chemical characterization results verified that the effects of active sites Ni, porous structure of lignin biochar support and electronic properties of the catalysts played a significiant role in HDO of lignin derived VAN. Additionally, synergistic effect of the highly homogeneously dispersed oxygen vacancies and acidic sites also promoted the VAN conversion efficiency. This work developed a strategy combing the advantages of MOFs and biomass derived substrates for manufacturing novel lignin/MOFs materials in the catalytic field.
研究领域:
化学工程
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环境科学
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催化材料
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DOI
高影响因子
AICHE JOURNAL
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2025
·
IF 4
Bin Chen,Xingwen Cha,Xuexue Dong,Juanjuan Bian,Jiale Huang,Qingbiao Li,Xiaoqing Huang,Guowu Zhan
Upgrading biomass-derived fatty acids through the H 2 -free and solvent-free catalytic deoxygenation process is both safe and eco-friendly. Herein, we used modified rice husk-derived biochar with ultra-high specific surface area and abundant surface groups as a support to design a homologous bimetallic site catalyst containing Ni single atoms (Ni 1 ) and Ni nanoclusters (Ni n ), the synergy between which is dedicated to excellent catalytic performance. The designed catalyst, Ni 1+n /A-bio-AC, demonstrated an impressive 89.8% selectivity for odd-numbered long-chain alkanes during the H 2 -free and solvent-free deoxygenation of stearic acid, with a turnover frequency value over 18 times higher than conventional Ni/AC. Multiple characterizations revealed the coexistence of Ni 1 and Ni n on the catalyst support. Experimental and theoretical calculations showed that Ni n facilitates the adsorption of fatty acid substrates. While Ni 1 serves as highly dispersed Lewis acid sites, enhancing the dehydrogenation of fatty alcohol intermediates during the in situ hydrodeoxygenation and lowering the decarboxylation pathway energy barriers via electronic synergy with Ni n , thus remarkably boosting the catalytic deoxygenation activity. This work provides a novel Ni dual-site catalyst for developing biomass resource conversion technologies.
研究领域:
催化化学
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生物质能
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环境科学
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产品关联
DOI
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
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2018
·
IF 4.805
Zhenhua Dong,Jinwei Yuan,Yongmei Xiao,Pu Mao,Wentao Wang
A rapid and practical protocol for the chemoselective deoxygenation of various aromatic ketones and aldehydes was described, which used a tandem catalyst composed of heterogeneous Pd/TiO2 + homogeneous FeCl3 with the green hydrogen source, polymethylhydrosiloxane (PMHS). The developed catalytic system was robust and scalable, as exemplified by the deoxygenation of acetophenone, which was performed on a gram scale in an atmospheric environment utilizing only 0.4 mol % Pd/TiO2 + 10 mol % FeCl3 catalyst to give the corresponding ethylbenzene in 96% yield within 10 min at room temperature. Furthermore, the Pd/TiO2 catalyst was shown to be recyclable up to three times without an observable decrease in efficiency and it exhibited low metal leaching under the reaction conditions. Insights toward the reaction mechanism of Pd-catalyzed reductive deoxygenation for aromatic ketones and aldehydes were investigated through operando IR, NMR, and GC-MS techniques.
研究领域:
有机化学
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催化化学
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2022
·
IF 16.744
Shuangmei Han,Xiaolei Zhang,Ruizhen Wang,Kui Wang,Jianchun Jiang,Junming Xu
The electrocatalytic hydrodeoxygenation (ECH) of lignin typical model compounds and lignin-derived oil from different tree species into (alkyl)-cyclohexane and (alkyl)-cyclohexanol in the fluidized electrocatalysis system were investigated in this research. The selected model compounds include two G-type compounds: eugenol (EO) and guaiacol (GO), and two S-type compounds: 4-allyl-2,6-dimethoxyphenol (4-DMP) and 2,6-dimethoxyphenol (2,6-DMP). This ECH system consisted of phosphotungstic acid (PW 12 ) electrolyte, catalyst that suspended in the electrolyte, and NaBH 4 reductant in the cathode. The results showed that 4-DMP could be converted using Pt/C as the catalyst at 25 mA/cm 2 current density and 80°C for 60 min, with higher faradaic efficiency of 90% and the selectivity of PCH and 4-PCH was 62% and 20%, respectively. For C O bond cleavage, the DFT calculations showed that, for EO, GO, and 4-DMP, the C-OCH 3 bond will be firstly broken, while for 2,6-DMP, it is preferred that C-OH bond will be firstly broken. It was found that G-type (EO, GO) was more easily hydrodeoxygenated than S-type (4-DMP, 2,6-DMP) compounds, with the reaction rate in the order of GO > EO > 2,6-DMP > 4-DMP, indicating that the allyl group had a negative effect on the electrocatalytic conversion. Furthermore, it was also found that the complete conversion of lignin-derived oil monomers of pine (mainly G-type) and poplar (mainly S-type) can be achieved, with the yield of target products (PCH and 4-PCH) of 64% and 43%, respectively. Overall, this work innovatively integrates biomass refining and electrocatalytic upgrading, which provides a green and environmentally friendly solution for lignin conversion and utilization.
研究领域:
化学工程
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环境科学
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生物质能
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产品关联
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
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2018
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IF 3.956
Shiyou Xing,Pengmei Lv,Che Zhao,Ming Li,Lingmei Yang,Zhongming Wang,Yong Chen,Shijun Liu
Non-H 2 and solvent-free catalytic conversion of waste lipids to liquid hydrocarbons is of great interest because of the associated low-cost, full-safety, and easy-operability. In this work, a solvent-free catalytic process for deoxygenating oleic acid was performed in H 2 and non-H 2 (N 2 , CH 4 , and CO 2 ) media over nano-Ni/HZSM-5. 8-Heptadecene, a primary product obtained at 320 °C in four media, was derived from the straightforward decarboxylation of oleic acid. In non-H 2 medium at 360 °C, the formation of C 8 –C 15 alkanes was enhanced, with yields of ca. 65.05 mol%, 70.71 mol%, and 73.09 mol% for N 2 , CH 4 , and CO 2 , respectively. A low yield of 49.67 mol% C 8 –C 15 alkanes in H 2 medium suggested that the H 2 medium reduced catalytic cracking . This was due to the preferential formation of stable heptadecane from 8-heptadecene in the presence of abundant H 2 . The absence of H 2 favored the cracking of 8-heptadecene. These cracked products were further converted to C 8 –C 15 alkanes, for which a mass supply of hydrogen was mandatory. Gas-phase reactions including methanation , Fisher-Tropsch (F-T) synthesis, and water-gas shift (WGS) reactions between deoxygenated gas products and reaction media provided significant pathways for the hydrogen required for the formation of alkanes. The CH 4 medium also acted as a hydrogen source due to its decomposition, catalyzed by nano-Ni/HZSM-5. Coke was substantially formed in all the four media. It was highlighted that the medium of H 2 favored the formation of aliphatic cokes, whereas the non-H 2 media, particularly the CO 2 medium, facilitated aromatic coke species on account of its weak oxidizability. Additionally, there was a severe loss of loaded Ni nanoparticles under H 2 medium but a slight Ni loss in CO 2 medium, which was proposed to the reason of aromatic cokes formation at the catalyst surface , acting as a trap for the loaded Ni nanoparticles.
研究领域:
化学工程
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能源科学
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DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2025
·
IF 6.2
Xingjie Guo,Qianqian Chen,Dingfu Wang,Pan Liu,Yingdong Zhou,Zhicheng Jiang,Bi Shi
Taking advantages of the structural features of lignin for its functionalization application benefits to develop a sustainable lignin biorefinery process. Herein, cage-like hollow carbon sphere (LC) with high stability and reducibility was fabricated by spray drying and controlled carbonization, due to the high content of carbon element and abundant phenolic hydroxyl groups of lignin. Spray drying would induce the self-assembly of lignin during solvent evaporation, and the introduction of KOH in this process increased the specific surface area of LC and created more surface defects. The controlled carbonization led to the cross-linking of lignin and partly retained the lignin polyphenolic structure, which could be used to adsorb and in situ reduce Pd 2 + to prepare Pd/LC catalyst. Owing to the synergistic catalytic effect of the abundant defect sites on the LC surface and the active Pd sites, the Pd/LC catalyst could catalyze the hydrodeoxygenation of vanillin to 2-methoxy-4-methylphenol under mild reaction conditions (90 °C, 1.5 h, 0.5 MPa H 2 ). Besides, the catalyst showed high activity after four cycles and universality for the other lignin-derived aromatic aldehydes.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
JOURNAL OF CATALYSIS
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2018
·
IF 6.759
Kairui Liu,Peifang Yan,Hong Jiang,Zhi Xia,Zhanwei Xu,Shi Bai,Z. Conrad Zhang
Selective hydrocleavage of aromatic C O bond while preserving the aromatic ring is a desired catalytic process in hydrodeoxygenation (HDO) of biomass derived aromatic oxygenates to high value biochemicals. Guaiacol with typical methoxy and phenolic hydroxyl groups is a representative aromatic di-oxygenates of lignin fragments. Sub-nanometer sized silver, a poor hydrogenation metal catalyst, was found to initiate H 2 dissociation and H spillover onto anatase TiO 2 (TiO 2 -A) surface. The spillover hydrogen enhanced the partial reduction of TiO 2 -A surface at a substantially lowered temperature as compared to the reduction of TiO 2 -A by molecular H 2 . The reduction of TiO 2 -A surface by spillover hydrogen was enhanced at Ag loading as low as 0.01 wt% on TiO 2 -A. The ratio of spillover H to Ag was as high as 675 at Ag loading of 0.01 wt% and the ratio decreased with increasing Ag loading. We found that the yield of phenolic products was linearly correlated with the amount of spillover hydrogen that created oxygen vacancy (Ov) through partial reduction of TiO 2 -A surface. Methanol was formed as the main side-product, indicating that the direct hydrocleavage of aromatic C-OCH 3 in guaiacol is favored over that of aromatic C-OH on the created site.
研究领域:
催化化学
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生物质能
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Catalysis
·
2016
·
IF 9.307
Jingbo Mao,Jinxia Zhou,Zhi Xia,Zhiguang Wang,Zhanwei Xu,Wenjuan Xu,Peifang Yan,Kairui Liu,Xinwen Guo,Z. Conrad Zhang
Gold nanoparticles on a number of supporting materials, including anatase TiO2 (TiO2-A, in 40 nm and 45 μm), rutile TiO2 (TiO2-R), ZrO2, Al2O3, SiO2 , and activated carbon, were evaluated for hydrodeoxygenation of guaiacol in 6.5 MPa initial H2 pressure at 300 °C. The presence of gold nanoparticles on the supports did not show distinguishable performance compared to that of the supports alone in the conversion level and in the product distribution, except for that on a TiO2-A-40 nm. The lack of marked catalytic activity on supports other than TiO2-A-40 nm suggests that Au nanoparticles are not catalytically active on these supports. Most strikingly, the gold nanoparticles on the least-active TiO2-A-40 nm support stood out as the best catalyst exhibiting high activity with excellent stability and remarkable selectivity to phenolics from guaiacol hydrodeoxygenation. The conversion of guaiacol (∼43.1%) over gold on the TiO2-A-40 nm was about 33 times that (1.3%) over the TiO2-A-40 nm alone. The selectivity of phenolics was 87.1%. The products are mainly phenolic compounds with no aromatics and saturated hydrocarbons such as cyclohexane. The gold particle size ranging from 2.7 to 41 nm and water content were found to significantly affect the Au/TiO2-A-40 nm catalyst activity but not the product selectivity. The reaction rates of 0.26 and 0.91 (min–1 g-cat–1 cm3) were determined for guaiacol hydrogenation and catechol hydrogenation, respectively. Bimolecular methylation was established as the dominant mechanism for methyl group transfer among the phenolics. Two major pathways of guaiacol hydrogenation to phenolics over the 0.4Au-19 nm/TiO2-A-40 nm are proposed: (1) direct hydrogenation of guaiacol to form phenol and methanol, (2) hydrodehydroxylation of catechol intermediate from the transmethylation between guaiacol and phenol.
研究领域:
化学工程
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催化科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Chemistry
·
2023
·
IF 13.1
Xinghua Zhang,Miaojia Song,Jianguo Liu,Qi Zhang,Lungang Chen,Longlong Ma
In this work, a “cyclopentanone-vanillin” strategy was proposed for the preparation of jet fuel range cycloalkanes from lignocellulose-derived ketones and lignin-derived aldehydes via aldol condensation and hydrodeoxygenation (HDO). Ethanolamine lactate ionic liquid (LAIL) exhibited excellent catalytic activity in the aldol condensation of cyclopentanone and vanillin. Desired mono-condensation and bi-condensation products were obtained with yield of 95.2% at 100 °C. It is found that the synergy effects between amino group of ethanolamine and hydroxyl group of lactic acid play a key role in the aldol condensation. The condensation products were converted into cycloalkanes by HDO over 5%Pd/Nb 2 O 5 catalyst. The density of the obtained HDO products is 0.89 g/cm 3 and the freezing point is lower than −60 °C. These results suggest that the resulted cycloalkanes can be used as additives to improve the density and low-temperature fluidity of the jet fuels.
研究领域:
生物化学
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能源化学
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产品关联
DOI
高影响因子
Nature Communications
·
2022
·Vol. 13
·期 1
·1-12
·
IF 17.694
Cui Zhihao,Dong Xing’an,Cho Sung Gu,Tegomoh Modeste N.,Dai Weidong,Dong Fan,Co Anne C.
Deoxygenation of aldehydes and their tautomers to alkenes and alkanes has implications in refining biomass-derived fuels for use as transportation fuel. Electrochemical deoxygenation in ambient, aqueous solution is also a potential green synthesis strategy for terminal olefins. In this manuscript, direct electrochemical conversion of vinyl alcohol and acetaldehyde on polycrystalline Cu to ethanol, ethylene and ethane; and propenol and propionaldehyde to propanol, propene and propane is reported. Sensitive detection was achieved using a rotating disk electrode coupled with gas chromatography-mass spectrometry. In-situ attenuated total reflection surface-enhanced infrared absorption spectroscopy, and in-situ Raman spectroscopy confirmed the adsorption of the vinyl alcohol. Calculations using canonical and grand-canonical density functional theory and experimental findings suggest that the rate-determining step for ethylene and ethane formation is an electron transfer step to the adsorbed vinyl alcohol. Finally, we extend our conclusions to the enol reaction from higher-order soluble aldehyde and ketone. The products observed from the reduction reaction also sheds insights into plausible reaction pathways of CO 2 to C 2 and C 3 products.
研究领域:
化学工程
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电化学
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能源科学
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）