CATALYSIS TODAY
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2020
·
IF 5.825
Jian Zhang,Zerui Su,Zhiyi Wu,Pingzhou Wang,Feng-Shou Xiao
Catalytic hydrogenolysis of lignin to produce arene monomers is promising for efficient utilization of lignocellulose. The acidic carrier supported metal nanoparticles exhibit excellent catalytic performance, while basic carrier was not often used. In this study, a basic hydroxyapatite supported Pt nanoparticles (Pt/HAP-3) were developed for the catalytic hydrogenolysis of alkaline lignin, achieving 15.1 % monomer yield. Characterizations of the catalysts and investigation on the basic sites show that high monomer yield is resulted from the synergy of suitable metal nanoparticles and sufficient basic sites of the carrier. This work might be helpful for preparation of efficient catalysts for the hydrogenolysis of lignin in the future.
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
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2025
·
IF 8.5
Zhen Wu,Zihe Zhao,Tao Wang,Sheng Chen,Yujie Wang,Yan Xu,Weisi Xu,Cong Liu,Haq Nawaz,Aiyong He,Lei Hu
Catalytic depolymerization is a favorable option for the valorization of industrial lignin. In this study, a new strategy was demonstrated for the efficient reductive depolymerization of industrial lignin based on a complex solvent of choline chloride-lactic acid (ChCl-LA) DES integrated with ethanol and a C-supported N-doped niobium-based catalyst with industrial lignin as carbon source (NBC@N-LC). It was found that the introduction of ethanol significantly improved the conversion of industrial lignin in ChCl-LA. More delightfully, depolymerization of industrial lignin in the complex solvent of DES-ethanol was further promoted by using the fabricated NBC@N-LC, exhibiting the best lignin dissolution performance, the lowest undepolymerized lignin yield of 21.9 % and the highest monomers yield of 31.8 %. 4-Ethylphenol was observed to dominate the monomers with 53.6 % selectivity, revealing the directional reactivity of the catalytic depolymerization process. Reaction pathway analysis showed that the synergistic effect of NBC@N-LC and DES-ethanol led to the efficient depolymerization of lignin, in which DES acted as an excellent solvent for lignin and depolymerized intermediates, ethanol acted as an in-situ hydrogen donor, and NBC@N-LC acted as a provider of reaction sites and acid active centers. In conclusion, this work offers a good alternative compared to the available lignin depolymerization method in terms of efficiency, selectivity, and cost aspects.
研究领域:
化学工程
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可再生资源利用
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环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Frontiers in Bioengineering and Biotechnology
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2022
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IF 6.064
Yang Guangxu,Gong Zhenggang,Luo Xiaolin,Shuai Li
Lignin structural analysis is important for the comprehensive utilization of lignin as well as delignification and bleaching during pulping while it is difficult to completely elucidate lignin structure due to its structural complexity and heterogeneity. Depolymerization of lignin into simple monomers via alkaline cupric oxide oxidation (OxCuO) followed by chromatographic analysis of the monomers is an effective method for lignin structural analysis. Here we revisited the OxCuO of lignin model compounds (monomers and dimers) and three representative lignocelluloses (i.e., Eucalyptus, Masson pine, and corn stover) to understand the effects of reaction conditions and lignin sub-structures on oxidation product yields and distributions. The improved OxCuO was found to be effective in oxidatively breaking the robust interunit C-C bonds in the β-β′ and β-5′ moieties of lignin other than β-O-4′ linkages at an elevated temperature (210°C). Further degradation of the monomeric oxidation products could also occur to reduce the monomer yields under a severe condition (i.e., high temperature and long reaction time). In addition, O2 inputs could reduce the monomer yields via nonselective overoxidation, thus having negative effects on accurate structural analysis of lignin. The O2 removal via ultrasonication combined with N2 flushing prior to the oxidation reaction could improve the monomer yield about 1.2 times (compared to that without O2 removal) at a low biomass loading of 5 wt%. By using the improved method of OxCuO, a monomer yield of 71.9% could be achieved from Eucalyptus (hardwood) lignin, which was much higher than conventional nitrobenzene oxidation (59.8%) and reductive depolymerization (51.9%). Considering the low cost, high availability, and low toxicity of CuO, the improved OxCuO could be a convenient and economic method for more accurate lignin structural analysis.
研究领域:
林业科学
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生物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
GREEN CHEMISTRY
·
2017
·Vol. 19
·期 8
·1895-1903
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IF 9.125
Yongxiang Zhai,Chuang Li,Guangyue Xu,Yanfu Ma,Xiaohao Liu,Ying Zhang
Lignin primarily composed of methoxylated phenylpropanoid subunits is an abundant biomass that can be used to produce aromatics. Herein, a series of non-precious bimetallic Ni–Fe/AC catalysts were prepared for efficiently depolymerizing lignin. When organosolv birch lignin was used to determine the efficiency of the catalysts in methanol solvent, the Ni1–Fe1/AC (the ratio of Ni and Fe was 1 : 1) achieved the highest total yield of monomers (23.2 wt%, mainly propylguaiacol and propylsyringol) at 225 °C under 2 MPa H2 for 6 h. From GPC analysis, it is also proved that lignin was efficiently depolymerized. The Ni–Fe alloy structure was formed according to XRD, HRTEM, H2-TPR and XPS characterization. Based on the model compounds’ tests, the Ni1–Fe1/AC catalyst showed high efficiency in ether bond cleavage without hydrogenation of aromatic rings which could be attributed to the synergistic effect of Ni and Fe on the alloy structure. The total yield of monomers by using the Ni1–Fe1/AC catalyst reached 39.5 wt% (88% selectivity to PG and PS) when birch wood sawdust was used as the substrate.
研究领域:
生物质化学
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催化化学
✓ 已验证
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
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2022
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IF 8.129
Bowen Luo,Linxuan Zhou,Zhipeng Tian,Yao He,Riyang Shu
Biochar is a promising support to prepare metal-based catalysts due to its large surface area and special porous structure . This work proposed a novel Ru-based biochar catalyst by using KCl and melamine as templates to produce micro-mesoporous structure and realize N-doping at the same time. The prepared Ru/NMC catalyst showed a good hydrogenolysis performance of cornstalk lignin in supercritical ethanol. A series of catalyst characterizations were carried out to reveal the effects of micro-mesoporous structure and N-doping on the lignin hydrogenolysis. The micro-mesoporous structure led to a large surface area, which favored the dispersion of metal site and facilitated the mass transfer and diffusion during lignin hydrogenolysis, while the N-doping formed abundant edge N atoms, which promoted the interaction and the electron transfer between the loaded Ru and the support. These two crucial factors synergistically improved the lignin hydrogenolysis, with 31.2 wt% monomer yield at the reaction temperature of 260 °C.
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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材料科学
✓ 已验证
产品关联
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2022
·
IF 11.889
Chao Liu,Bingyang Liu,Xing Wang,Zhanghong Xie,Lili Tong,Xiangchen Kong,Yuyang Fan,Rui Xiao
Tandem strategy for lignin utilization with photocatalytic preoxidation and ultrasonic cavitation depolymerization was proposed. Cornstalk residual lignin from industrial bioethanol process was first photocatalytically preoxidized under visible light by g -C 3 N 4 and WO 3 / g -C 3 N 4 / h -BN (WCB) photocatalysts respectively, then obtained lignin samples were characterized to confirm the preoxidation with raw lignin as a blank. During photocatalytic preoxidation, benzyl hydroxyls in lignin was transformed to carbonyls, but a certain degree of lignin degradation and condensation was observed. In comparison, WCB-catalyzed photopreoxidation was more effective. Thereafter, lignin depolymerization was achieved by ultrasonic cavitation-assisted ethanololysis under optimal conditions. Compared with the mere ultrasonic cavitation depolymerization of pristine lignin, WCB-induced photocatalytic preoxidation improved the conversion rate by 14%, the light-oil yield by 26%, and the phenolic monomer yield by 35%. In general, the reported tandem method worked very well for the enhancement of lignin depolymerization and provided a new idea for the development of lignin valorization.
研究领域:
化学工程
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环境科学
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材料科学
✓ 已验证
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）