ChemSusChem
·
2016
·Vol. 10
·期 3
·523-532
·
IF 7.116
Haiwei Guo,Bo Zhang,Zaojuan Qi,Changzhi Li,Jianwei Ji,Tao Dai,Aiqin Wang,Tao Zhang
Graphical W 2 C activity : Non-noble metal catalyst tungsten carbide shows high activity in the selective deconstruction of various lignin feedstocks to phenolic oils, and the impact of the structure differences on the activity of tungsten carbide is well studied. Softwood lignin shows lower hydrocracking efficiency than hardwood lignin, mainly owing to the higher molecular weights and the existence of more resistant linkages. Lignins isolated from representative hardwood, softwood, and grass materials were effectively hydrocracked to aromatics catalyzed by tungsten carbide over activated carbon (W 2 C/AC). The effects of botanical species and fractionation methods on lignin structure and the activity of W 2 C/AC were studied in detail. Gas permeation chromatography (GPC), FTIR, elemental analysis, and 2 D HSQC NMR showed that all the extracted samples shared the basic skeleton of lignin, whereas the fractionation method significantly affected the structure. The organosolv process provided lignin with a structure more similar to the native lignin, which was labile to be depolymerized by W 2 C/AC. Softwood lignins (i.e., spruce and pine) possessed higher molecular weights than hardwood lignins (i.e., poplar and basswood); whereas corn stalk lignin that has noncanonical subunits and exhibited the lowest molecular weight owing to its shorter growth period. β-O-4 bonds were the major linkages in all lignin samples, whereas softwood lignins contained more resistant linkages of β-5 and less β-β than corn stalk and hardwood lignins; as a result, lowest hydrocracking efficiency was obtained in softwood lignins, followed by corn stalk and hardwood lignins. 2 D HSQC NMR spectra of lignin and the liquid oil as well as the solid residue showed that W 2 C/AC exhibited high activity not only in β-O-4 cleavage, but also in deconstruction of other ether linkages between aromatic units, so that high yield of liquid oil was obtained from lignin.
研究领域:
化学工程
·
生物质能
✓ 已验证
产品关联
DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
·
2023
·
IF 11.4
Jiayi Zheng,Liheng Chen,Xueqing Qiu,Yingchun Liu,Yanlin Qin
Lignin is the most abundant natural phenolic polymer. However, the severe condensations of industrial lignin resulted in an undesirable apparent morphology and darker color, which hindered its application in the field of daily chemicals. Therefore, a ternary deep eutectic solvent is used to obtain lignin with light-color and low condensations from softwood. The results showed that the brightness value of lignin extracted from aluminum chloride-1,4-butanediol-choline chloride at 100 °C and 1.0 h was 77.9, and the lignin yield was 32.2 ± 0.6%. It is important that 95.8% of β-O-4 linkages (β-O-4 and β-O-4′) was retained. Lignin is used to prepare sunscreens and is added to physical sunscreens at 5%, with SPF up to 26.95 ± 4.20. Meanwhile, enzyme hydrolysis experiments and reaction liquid composition tests were also conducted. In conclusion, a systematic understanding of this efficient process could facilitate high-value utilization of lignocellulosic biomass in industrial processes.
研究领域:
生物化学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
WOOD SCIENCE AND TECHNOLOGY
·
2023
·Vol. 57
·期 4
·879-901
·
IF 3.4
Luo Lingcong,Zhang Qianqian,Lan Yuling,Deng Jianping,Lin Yang,Du Guanben,Zhao Weigang
High-performance electrodes of activated carbons (PNOACs) with P, N, and O heteroatoms were prepared through a simple one-step phosphoric acid activation method without the need for any dopants or post-treatment. In the preparation procedure, cork biomass material from Quercus variabilis was used as the precursor, and phosphoric acid was used as both the phosphoric resource and the activation agent. The pore structure, morphology, and physicochemical properties of the as-prepared carbons were investigated. In addition, the electrochemical performances of the PNOACs were evaluated using three-electrode and two-electrode systems (symmetric supercapacitor, AS). The results indicated that cork is promising as a low-cost and environmental-friendly precursor for producing high-performance supercapacitors electrode. Furthermore, galvanostatic charge–discharge analysis revealed a specific capacitance of 206 F g −1 at a current density of 0.5 A g −1 , which can be attributed to the excellent hierarchical pore structure (micro-, meso-, and macropores) and suitable pore size distribution of the PNOACs. The specific surface area and total pore volume as high as 515.80 m 2 g −1 and 0.29 cm 3 g −1 were obtained, respectively. The presence of heteroatoms, namely N (0.81–1.07%), P (0.52–2.06%), and O (15.87–19.18%) content, on the carbon surface resulted in a considerable enhancement in the capacitive performance. Furthermore, a PNOAC sample, prepared at 600 °C with a mass ratio of 1:1, exhibited high long-term cycling stability (84.5%) and an energy density of 15.03 W h kg −1 . Therefore, cork is highly promising as an electrode material for supercapacitors to attain exceptional electrochemical performance, as well as provide a new possibility for the utilization and valorization of high-value cork waste.
研究领域:
材料科学
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能源存储
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL PROCESSING TECHNOLOGY
·
2022
·
IF 8.129
Xiongjian Du,Shubin Wu,Tengfei Li,Yihui Yin,Jingmo Zhou
To enhance the efficiency and environmentally friendliness of the pyrolysis of lignin, we investigated the effects of ozone oxidation pretreatment on the softwood lignin structure and pyrolysis product distribution during the pyrolysis process. Fundamental characteristic analysis shows that the structure of lignin after pretreatment changed compared with that of the original lignin. The lignin side chain hydroxyl was oxidized to carbonyl or carboxyl, enhancing the depolymerization of lignin. 2D HSQC NMR analysis reveals that pretreatment mainly interrupted unstable chemical bonds like ether linkage of lignin. In order to determine the effect of pretreatment on pyrolysis, the pyrolysis experiment was performed on raw and pretreated lignin separately. Results showed that the pretreatment improves the yield of bio-oil from lignin pyrolysis. Furthermore, the relative content of p -hydroxyphenyl type phenols derived from lignin pyrolysis is positively correlated with the oxidation degree. Thus, the pretreatment has great potential in improving aromatic production during pyrolysis of lignin, and could selectively transform lignin to high value-added platform compounds.
研究领域:
生物质能
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化学工程
·
环境科学
✓ 已验证
DOI
高影响因子
Polymers
·
2022
·Vol. 14
·期 23
·5064
·
IF 4.967
Jingrong Sun,Jinmeng Bai,Jingjing Li
In order to develop a bio-based epoxy resin with high mechanical and thermal performance, cork particles and nanocellulose were introduced into the rosin-based epoxy resin to improve the toughness, stiffness and thermal stability. The flexural properties of the epoxy composites indicated that the strength and modulus were reduced when the content of cork particles was relatively high (>3%) due to the low stiffness and modulus of cork itself. However, the flexural performance was significantly improved after the addition of 1% nanocellulose. In contrast to the flexural properties, the impact toughness results showed the synergistic toughening effects of nanocellulose and cork particles on the rosin-based epoxy resin. The highest impact toughness of 13.35 KJ/m2was found in the epoxy composite with 1% cellulose nanofibers and 3% cork particles, an increase of 149.07% compared to the neat epoxy. Cork particle size also had a significant effect on the mechanical properties of the composites. Both the flexural and impact results showed first a rise and then a fall with a decrease in the cork size. TGA results indicated cork particles and nanocellulose could have a synergistic enhancing effect on the thermal stability of the rosin-based epoxy resin. This work can add value to rosin and cork waste and widen the industrial applications of the epoxy resin.Keywords:rosin-based epoxy resin;cork;nanocellulose;toughening;strengthening
研究领域:
材料科学
·
生物复合材料
✓ 已验证
DOI
PubMed
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2023
·
IF 6.6
Guotao Liang,Yanran Qi,Ruizhi Gong,Yongzhi Hu,Fengbiao Yao,Yiliang Liu,Baoxuan Liu,Yueying Zhao,Yong Dai,Xiaoying Dong,Fengqiang Wang,Yongfeng Li
Cork materials have the property of elastic deformation under pressure due to their unique closed, porous, cell structure with thin cell wall; and they accordingly need a surface coating that matches their deformation during there being used as floor materials. However, traditional wood coatings are hard, brittle, and mostly suitable for stiff wood surfaces, which are difficult to be directly adapted to the requirements of flexible cork. Although waterborne polyurethane (WPU) has the advantage of property tailorability, its fully applicable to cork materials are still a challenge. Herein, this study utilized a simple physical blending of waterborne polyurethane and nanocellulose with high aspect ratio, to develop a high-strength coating that matches the elastic deformation requirements of cork materials. When both two kinds of nanocellulose , poplar wood nanocellulose (WCNF) with an aspect ratio of 800 and bacterial nanocellulose (BCNF) with an aspect ratio of 2000, was individually added into the WPU emulsion at 0.5 wt%, the tensile strength and elastic modulus of the nanocellulose-modified polyurethane coating increased by 48.58 % and 118.88 %, 54.50 % and 120.48 %, respectively, compared to those of the pure WPU coating (14.09 MPa and 312.74 MPa). It is notable that both the nanocellulose-modified coatings showed no signs of damage on the cork surface even they underwent continuous bending over 2000 cycles, which indicates their excellent flexural fatigue resistance . Interestingly, such nanocellulose-modified coatings maintain comparable transparency, gloss, adhesion, solvent resistance and even present slightly improved hardness and wear resistance than their pure WPU coatings. Overall, the two nanocelluloses are comparative to the modification of the coatings, both of which could match the elastic deformation requirements of cork materials. Therefore, the nanocellulose physically blended polyurethane technology provides a simple and effective solution for the design and property tailoring of flexible coatings for cork floor.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
Analytical Methods
·
2023
·Vol. 15
·期 29
·3510-3521
·
IF 3.1
Na Hang,Yang Yang,Yuyue Zang,Wanning Zhao,Jing Tao,Songqing Li
This study assessed the use of magnetic biosorbents in dispersive solid-phase extraction with a gas chromatograph-electron capture detector for the determination of trifluralin, chlorothalonil, transfluthrin, bromopropylate, and bifenthrin in water samples. To our knowledge, this is the first time that magnetic cork composites are used as an adsorbent in dispersive solid-phase extraction. The advantages of magnetic cork composites include their density regulation and high surface areas. The magnetic composites can be recovered using a magnetic field for desorption purposes, which can improve the operation process and reduce the extraction time. Moreover, the parameters affecting the extraction performances were optimized. The method has a limit of detection between 0.30 and 2.02 μg L−1. Good linearities (R2 > 0.99) were obtained in the linear range of 1.00 to 2000 μg L−1. The relative recoveries of the analytes in tap water, river, and lake water samples spiked at different concentrations ranged between 90% and 104%, and the relative standard deviations were less than 7.1%. Therefore, this study showed that Fe3O4/cork magnetic composites can be used as efficient and eco-friendly biosorbents in dispersive solid-phase extraction for the determination of pesticides in water samples. The use of these composites contributes to the current trend of green chemistry.
研究领域:
环境科学
·
分析化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2024
·
IF 5.6
Yu Sun,Yongjian Xu,Wenjing Li,Xiaopeng Yue
Natural fiber-based sound-absorbing materials have received more and more attention due to the increasingly severe noise pollution. However, the current natural fibers’ sound-absorbing materials often have poor flame-retardant performance and degradability, which limits their further application. In this study, flame-retardant cellulose fiber (FRCF) was prepared by modifying softwood fiber, and a kind of fiber-based sound-absorbing material, natural fiber-based sound-absorbing composite (NFSC), was prepared by replacing glass fiber with FRCF. The results show that the synthesis of FRCF is successful, and the functional groups containing phosphorus and nitrogen introduced into the cellulose side chain can significantly improve the thermal stability of softwood fiber. FRCF is able to bestow initial flame-retardant capability on the NFSC, allowing NFSC to get the V-1 level in vertical burning test with fewer flame retardants, and the limiting oxygen index (LOI) of NFSC can reach 28.5 %. The NFSC with FRCF instead of glass fiber also has better sound absorption performance; its maximum sound absorption coefficient reaches 0.90, and its noise reduction coefficient (NRC) reaches 0.45. This work is expected to provide inspiration for the design and preparation of environmentally friendly natural fiber-based sound-absorbing materials.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2021
·
IF 9.381
Xiaoning Tang,Gaozhe Liu,Heng Zhang,Xin Gao,Meng Li,Shumei Zhang
In this study, we report a novel, facile, and green method that was used for creating a new all-cellulose composite (ACC) based on inorganic molten salt solvent. Three representatively native fibers from softwood ( Pinus kesiya ), hardwood ( Eucalyptus globulus ), and agricultural straw ( Zea mays ) were selected to verify the effect of the method. The welded sheets were thoroughly characterized and compared. Cellulose sheets from the pine exhibited excellent mechanical properties (σb 16.94 MPa) and thermal stability (T max 265 °C) after the welding process, while the corn stalk sheets displayed more robust and thermostable features than the eucalyptus. The welding technique using inorganic metal salt hydrate provides a promising and convenient route to obtain firm sheet-materials with micro- or nano-structures from nature fibers.
研究领域:
材料科学
·
林业工程
·
绿色化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FUEL
·
2023
·
IF 7.4
Xin Xu,Kai Wang,Yubo Zhou,Chenhuan Lai,Daihui Zhang,Changlei Xia,Arivalagan Pugazhendhi
Organosolv pretreatment has been verified to facilitate the enzymatic hydrolysis by efficient delignification. Recently, novel solvents derived from biomass have been applied in lignocellulose pretreatment. However, few studies on the pretreatment of softwood with novel solvents have been reported. In this study, organosolv pretreatments with three green solvents, including γ-valerolacton (GVL), tetrahydrofuran (THF), and 2-methyltetrahydrofuran (2-MTHF), were performed on masson pine, and compared with conventional ethanol (EtOH) pretreatment. The results showed that GVL pretreatment exhibited the best performance for removing lignins from masson pine, achieving a pretty high lignin removal ratio of 87.2 % at 150 °C with 75 mM H 2 SO 4 . Correspondingly, the highest glucose yield of 76.8 % was observed in the enzymatic hydrolysis of GVL pretreated masson pine with a relatively low cellulase loading (20 FPU/g glucan). The relations between relative energy difference of the solvent-lignin interactions and both of the lignin removal and enzymatic digestibility of organosolv pretreated substrates were evaluated. Furthermore, the structural features of four organosolv lignins were characterized, including molecular weights, functional groups, inter-unit linkages and aromatic information. The results provide a better understanding of organosolv pretreatment effects on enzymatic digestibility of softwood biomass, and give comprehensive lignin properties for valorization of organosolv lignins from softwood.
研究领域:
生物化学
·
可再生资源与环境工程
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2020
·
IF 4.244
Pan Tao,Jingjing Li,Jian Li,Shibin Shang,Zhanqian Song
Rosin-based epoxy composites with high-impact toughness, tensile strength, modulus, and excellent flame retardance were prepared through a simple and effective approach. In this study, rosin-based epoxy resin (acrylopimaric diglycidyl ester, APA-ER) was synthesized from rosin, and the chemical structures of the products were determined by 1 H NMR and FT-IR. The multiwalled carbon nanotubes (MWCNTs) and cork powders were introduced to the APA-ER to enhance the mechanical and thermal properties of epoxy composites. For the first time, cork powder was used to reinforce the modified rosin-based epoxy resin. Testing results of the mechanical properties indicated that the impact toughness of epoxy composite with 1.5 wt% MWCNTs and 3 wt% cork powders (100–200 mesh) had the highest value (12.34 and 12.04 kJ m −2 ), which was increased by 324% and 314%, respectively, compared to pure resin (2.91 kJ m −2 ). The composites with 1.5 wt% MWCNTs displayed better flexural and tensile performance compared to APA-ER/Cork. Moreover, the DMA, TG, and cone calorimeter results showed that APA-ER/Cork had a better performance in thermal stability and flame retardance than APA-ER/MWCNTs. Additionally, the flame retardance of rosin-based epoxy resin was further improved by adding MWCNTs and cork powder simultaneously. These results showed that the rosin-based epoxy resin could be toughened and strengthened effectively, and the thermal performance was improved by MWCNTs and cork powders. In conclusion, the value-added development of rosin and cork products was increased and applied in the field of functional materials.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2025
·
IF 6.2
Chenjie Ji,Rou Weng,Chang Yu,Yuyang Fan,Jia Ouyang
This study addresses the critical challenges of softwood pretreatment, focusing on Chinese fir as a model substrate to tackle its high lignin content and recalcitrant structure. To enhance the fractionation efficiency of softwood components and improve enzymatic glucose yield, four deep eutectic solvent (DES) systems—ChCl/LA, ChCl/FA, TEBAC/LA, and TEBAC/FA—were systematically evaluated. Using density functional theory (DFT) calculations and molecular dynamics (MD) simulations, TEBAC/LA (1:4) was identified as the optimal DES system, exhibiting exceptional binding energy (-162.37 kcal/mol) and strong hydrogen bonding interactions that effectively disrupted lignin’s hydrogen bond network. Furthermore, Pearson correlation analysis between the physicochemical properties of DES (e.g., density, viscosity, surface tension, and Kamlet-Taft parameters) and enzymatic hydrolysis yield revealed that low surface tension, high Kamlet-Taft α, and high π parameters significantly enhance pretreatment efficiency. Guided by these computational insights, experimental validation revealed that TEBAC/LA achieved outstanding lignin removal (97.41 %) and glucose yield (97.09 %) under optimized conditions (150 °C, 90 min). This work not only advances the understanding of DES-biomass interactions but also demonstrates the power of integrating molecular simulations with experimental validation to design efficient biomass pretreatment systems. This study provides a scalable and sustainable approach for optimizing solvent systems, advancing renewable energy and material production.
研究领域:
生物能源
·
林产化学
·
计算生物学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）