Molecular Catalysis
·
2024
·
IF 3.9
Tao Lv,Kexin Wei,Ting Wang,Xiao Wang,Zuguang Liu
A carbon-based acid was prepared by the sulfonation of activated carbon derived from eucalyptus wood waste, a solid waste from wood processing, and characterized by SEM, BET, FT-IR, Raman, XRD and XPS. Due to activation by phosphoric acid and subsequent sulfonation, the resultant carbon-based solid acid can obtain a porous structure, medium surface area and abundant functional groups including sulfonic groups, carboxyl, hydroxyl and other oxygen-containing groups, which provides excellent mass transfer channels and sufficient reactive sites for catalytic reactions. So, the carbon-based solid acid showed excellent catalytic performance for converting α -pinene to camphene with a conversion of up to 99.8 % and a selectivity of 51.2 %, respectively. Quantum chemical theoretical calculations (electrostatic potential, Gibbs free enthalpy of intermediates, molecular size) are used to further analyze the catalytic mechanism of carbon-based solid acids. Theoretical analysis of the carbon positive ions and their energies as well as experimental results under electron-donating co-catalysts suggests that oxygen-containing functional groups on carbon-based solid acids play an important role in improving α- pinene adsorption onto catalyst as well as camphene selectivity. This work provides a promising approach for converting α -pinene to camphene catalyzed by carbon-based solid catalyst.
研究领域:
化学工程
·
催化科学
✓ 已验证
产品关联
DOI
高影响因子
Colloid and Interface Science Communications
·
2020
·
IF 2.831
Mingchu Xia,Tao Yang,Shiyao Chen,Guangming Yuan
In this study, a simple and cost-effective method was developed to fabricate superhydrophobic coating on wood surface. The prepared superhydrophobic coating had a large water contact angle (159°), less water slide angle (6°), good durability, abrasion resistance property, excellent thermal stability, and good acid and alkali resistance property. Notably, the coatings had self-cleaning properties in air or oil environment. The superhydrophobic coating was characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and Fourier transform infrared (FTIR) spectroscopy. We prepared the classical micro/nanostructured SiO 2 on the wood surface on which the low surface free energy substance 1H,1H,2H,2H-perfluoroalkyltrichlorosilane (PFDS) was successfully modified. Furthermore, the treated wood had significantly better physical properties including water uptake and dimensional stability. The developed superhydrophobic coating is easy to fabricate and has great significance for the functional modification of wood.
研究领域:
材料科学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2024
·
IF 5.6
Wenchao Jia,Tianyuan Xiao,Yanzhu Guo,Pedram Fatehi,Yanning Sun,Meihong Niu,Haiqiang Shi
Condensed lignin formed during eucalyptus woodchip pre-hydrolysis adversely affects subsequent enzymatic saccharification , and phenolic additives are popular lignin condensation inhibitors. The goal of this project was to reveal the mechanisms of lignin modification by phenolic additives during woodchip pre-hydrolysis and its effects on subsequent enzymatic saccharification. The HSQC and 31 P NMR analyses confirmed that resorcinol with three electrophilic substitution of active sites could act as a cross-linking agent to promote the formation of condensed lignin, whereas 2-naphthol and sodium 2-naphthol-7-sulfonate could block benzyl carbocations and reduce the formation of condensed lignin. Interestingly, the introduction of sulfonic acid groups increased the electrostatic repulsion between enzyme and lignin as well as increased the hydrophilicity of lignin, thereby greatly reducing non-productive adsorption and physical obstacle effects. Sodium 2-naphthol-7-sulfonate as an efficient benzyl carbocations scavenger reduced the non-productive adsorption and physical obstacle effects of lignin by 82.4% and 13.3%, respectively.
研究领域:
生物化学
·
林产化学工程
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2022
·
IF 6.449
Shiqin Liu,Yuxiang Huang,Qiuqin Lin,Yanglun Yu,Wenji Yu
Wood is a traditional green and renewable environmental-friendly material, but some wood with high polyphenol content is prone to irregular color changes during processing. In this study, ferrous ion (Fe (II)) solution of various mass fractions (0.05%, 0.1%, 0.5%, 1%) was used to immobilize polyphenols in eucalyptus veneers and induce discoloration. With the increase of the Fe (II) concentration, the complexes formed by Fe (II) and polyphenols in the veneers not only enriched the surface, but also began to gather in the cell cavity of wood rays and vessels. The overall color of the veneers became darker and the surface became more hydrophobic with a maximum contact angle of 120°. In addition, the 40-hour xenon lamp aging test showed that the veneer treated with 0.1% Fe (II) had the best light-aging resistance and its color difference was less than 7 and remained stable. Eucalyptus veneers with induced discoloration can not only avoid irregular color changes in subsequent processing, but also meet the differences in people's esthetic perception.
研究领域:
材料科学
·
木材化学
·
表面化学
✓ 已验证
产品关联
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2018
·
IF 5.807
Xianfeng Hou,Zhinan Wang,Jin Sun,Meng Li,Shujie Wang,Kai Chen,Zhenzhong Gao
A novel pretreatment strategy based on combination of microwave and ionic liquid [TBA][OH] was developed for enhancing enzymatic hydrolysis of Eucalyptus sawdust. The sugar yield of pretreated sample achieved 410.67 mg/g in 48 h, which suffered from optimized microwave-assisted [TBA][OH] pretreatment. The work mechanism was illuminated by chemical composition, Fourier transform infrared spectroscopy (FTIR), 13 C cross polarization/magic-angle spinning solid state NMR ( 13 C solid NMR), X-ray diffraction (XRD) and scanning electron microscope (SEM) analyses. The combined effect of microwave and [TBA][OH] leads to the violent deconstruction of lignin, removal of hemicelluloses, destruction of crystalline region and an eroded, pored and irregular micro-morphology. As a green, relatively inexpensive and high efficient pretreatment, microwave-assisted [TBA][OH] pretreatment has great potential in the field of bio-refinery.
研究领域:
生物能源
·
植物化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Polymers
·
2020
·Vol. 12
·期 2
·378
·
IF 3.426
Qilin Zhang,Haichao Li,Zongwei Guo,Feng Xu
A simple and economical biorefinery method, organosolv methyl isobutyl ketone (MIBK) pretreatment assisted by Lewis acid ferric trichloride hydrolysis, was proposed for fractionating the lignin from extractive-freeEucalyptuspowder at the nanoscale, accompanied by another product furfural, derived from hemicellulose. Under the conditions (180 °C, 1 h) optimized based on the best yield of furfural, 40.13% of the acid-insoluble lignin (AIL) could be obtained with a high purity of 100%, a low molecular weight of 767 (Mn) and improved thermostability. The extracted lignin was characterized by its chemical structure, thermostability, homogeneity, molecular weight, and morphology as compared with milled wood lignin (MWL). The results showed significant variations in chemical structures of the extracted lignin during the pretreatment. Specifically, the aryl ether linkage and phenylcoumarans were broken severely while the resinols were more resistant. The G-type lignin was more sensitive to degradation than the S-type, and after the pretreatment, H-type lignin was formed, indicating the occurrence of a demethoxylation reaction at high temperature. Moreover, the lignin nano-particles were identified visually by AFM and TEM images. The dynamic light scattering (DLS) showed that the average diameter of the measured samples was 131.8 nm, with the polydispersity index (PDI) of 0.149. The MIBK-lignin nano-particles prepared in our laboratory exhibit high potentials in producing high functional and valuable materials for the application in wide fields.Keywords:lignin nano-particles;organosolv pretreatment;Eucalyptuswood;biomass;biorefinery
研究领域:
化学工程
·
材料科学
·
生物质技术
·
生物技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
HOLZFORSCHUNG
·
2023
·Vol. 77
·期 6
·437-452
·
IF 2.4
Haonan Zhang,Qi Liu,Yanchen Zhu,Zhang Feng,Hao Ren,Huamin Zhai
In this study, representative lignin samples differing in hydroxyl content, molecular weight, linkage composition and lignin units ratio were prepared from eucalyptus wood by different isolation means and modification means: milled wood lignin (MWL), kraft lignin classified at different pH (KL), lignocresol (LC), lignoresorcinol (LR), lignopyrogallol (LP) as well as lignocresol secondary functional switched samples (LC 2 nd deriv). The structure of various lignins was characterized in detail by Fourier transform infrared (FT-IR) spectroscopy, gel permeation chromatography (GPC) and nuclear magnetic resonance (NMR). In order to eliminate the interference of other factors, bovine serum albumin (BSA) with relatively simple protein structure and different kinds of lignin and their derivatives were selected as the research objects. The adsorption/desorption behavior and mechanism between lignin samples and BSA were studied by quartz crystal microbalance with dissipation monitoring (QCM-D). The results showed that the content of phenolic hydroxyl was the main factor affecting the interaction of lignin and BSA, but in addition, the molecular size, linkages composition and the types of lignin units also had important effects on its adsorption behavior. The research will provide theoretical guidance and all-round reliable basic data for the interaction of lignin on lignocellulose hydrolysis enzymes in industrial application.
研究领域:
生物化学
·
材料科学
✓ 已验证
DOI
高影响因子
FIBERS AND POLYMERS
·
2016
·Vol. 17
·期 9
·1330-1335
·
IF 1.022
Zhang Dezhi,Liu Mengru,Liu Yingying,Li Hailong
There is a challenge to find an effective and eco-friendly method to achieve the modification of fibers. The effect of laccase-TEMPO system on the properties of the bleached eucalyptus kraft pulp was investigated in this work. The results were demonstrated by the decreases in curl values and kink index. In addition, carboxyl and aldehyde groups were introduced in this reaction system. Compared with initial pulp, the contents of aldehyde and carboxyl groups of the treated pulp were increased from 42.6 μmol/g, 8.4 μmol/g to 125.4 μmol/g, 26.3 μmol/g respectively. However, the treatment had a detrimental effect on the thermal stability of pulp fibers. Moreover, the crystallinity index was slightly increased (from 82.1 % to 83.8 %) after the TEMPO-mediated oxidation, but the native crystalline structure was nearly unchanged. Furthermore, after the oxidation treatment, the relatively smooth film surface became textured, the carbon and oxygen bonds were changed, which were investigated by scanning electron microscope and X-ray photoelectron spectroscopy.
研究领域:
生物化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
GREEN CHEMISTRY
·
2021
·Vol. 23
·期 7
·2738-2746
·
IF 10.182
Feiyun Li,Feiyang Qin,Yuxia Pang,Hongming Lou,Cheng Cai,Weifeng Liu,Yong Qian,Xueqing Qiu
In order to reduce the enzyme cost of lignocellulosic enzymatic hydrolysis, upper critical solution temperature (UCST) additives are used to recover and reuse cellulase by regulating the temperature. A sulfobetaine polymer, PSPE, showed a sensitive UCST response in buffer, and its UCST-performance was optimised by adjusting the molecular weight of the polymer. PSPE-3 (Mw = 355.1 kDa) was added to the cellulase buffer at 50 °C, and PSPE-3 and cellulase were co-precipitated by cooling to the room temperature of 25 °C. PSPE-3 and cellulase co-precipitated mainly through hydrophobic interactions via cooling. Compared with octadecyl sulfobetaine (SB3–18), PSPE-3 had a more sensitive UCST response and stronger cellulase recovery ability. Adding only 40% PSPE-3 (accounting for the mass fraction of cellulase) can save more than 50% cellulase in the enzymatic hydrolysis system of eucalyptus chips pre-treated with dilute acid (Eu-DA). However, for the Eu-DA system, adding 100% SB3–18 can only save about 30% of cellulase. In this work, efficient recycling of cellulase was achieved at room temperature by adding UCST-type PSPE. The process is green without consuming acid and alkali, and this work provides a new idea for reducing the production cost of cellulosic ethanol.
研究领域:
生物化学
·
可再生资源与环境工程
✓ 已验证
DOI
高影响因子
WOOD SCIENCE AND TECHNOLOGY
·
2022
·Vol. 56
·期 1
·305-322
·
IF 2.898
Li Mingfu,Liu Yi,Chen Chunlin,Zhang Jian,Wang Shuangfei,Min Douyong
The hot water and green liquor pretreatments were conducted on Eucalyptus wood in the current study. The cellulase adsorption behavior on the isolated lignins and model compounds was clarified by a quartz crystal microbalance with dissipation (QCM-D) and atomic force microscopy (AFM). The QCM-D analysis indicated that the hot water pretreated lignin (HPL) adsorbed more cellulase than the green liquor pretreated lignin (GPL) and the protolignin (PL). The AFM analysis revealed that the interaction force between lignin and cellulase was in the order of HPL > GPL > PL which was consistent with the cellulase adsorption. The monomeric lignin model with the ketone group adsorbed more cellulase than the counterpart with the hydroxyl group or aldehyde group. The dimeric lignin models adsorbed more cellulase than the monomeric lignin models. Furthermore, the β – β dimer model adsorbed more cellulase than the β–5 and 5–5′ dimer models. This study provides fundamental knowledge for developing more efficient pretreatment technologies.
研究领域:
生物化学
·
生物技术
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2023
·
IF 5.2
Ruiqian Tao,Nianrong Feng,Jiahua Li,Bochen Li,Yugui Lv,Kenan Li,Dongying Hu
The development of flexible self-luminous reversible thermochromic passive energy-saving composites (TPCMs) is self-challenge due to the defects of easy leakage, non-visibility, solid phase rigidity, and weak light absorption . So, the emerging TPCMs were cleverly constructed using wood aerogel as support skeleton and different mass ratios of natural latex/long afterglow components as flexible and self-luminescent matrix based on optimal binary fatty alcohol eutectic (C 14 C 20 ). Among them, C 14 C 20 R-TEW-1R and C 14 C 20 G-TEW-0.35 P stand out with suitable phase transition temperatures (28.8 °C and 29.7 °C), high latent heat values (100.5 J g −1 and 119.4 J g −1 ), and low supercooling (0.7 °C and 0 °C). Induced by phase change, they change from rigid to flexible, from red/green to milky white, and can absorb light to achieve self-luminescence in the dark (orange red and blue-green) and enhanced photothermal efficiency. Beyond the traditional thermal/light stability and excellent anti-leakage performance, TPCMs realizes the combination of temperature sensitivity/control and self-luminous, providing broad application prospects in home automation, passive energy-saving in buildings, luminescent response switches, and other fields.
研究领域:
材料科学
·
能源材料
·
热管理
·
复合材料
·
智能材料
·
建筑能效
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）