BIORESOURCE TECHNOLOGY
·
2015
·
IF 4.494
Bing Yan,Kunlan Li,Ligang Wei,Yingchong Ma,Guolin Shao,Deyang Zhao,Wenying Wan,Lili Song
The treatment of enzymatically hydrolyzed lignin (EHL) in dialkylimidazolium-based ionic liquid (IL)–water mixtures (50–100 wt% IL content) was investigated at 150 °C for 3 h. pH, IL type, and IL content were found to greatly influence the degradation of lignin and the structure of regenerated lignin. 1-Butyl-3-methylimidazolium methylsulfonate–water mixtures with low pH facilitated lignin depolymerization but destroyed the regenerated lignin substructure. Regenerated lignin with low molecular weight and narrow polydispersity index (2.2–7.7) was obtained using a 1-butyl-3-methylimidazolium acetate-based system. Water addition inhibited lignin depolymerization at 50–100 wt% IL content, except for 70 wt% 1-butyl-3-methylimidazolium chloride–water mixture. Compared with pure IL treatment, obvious differences were observed in the breakdown of inter-unit linkages and ratio of syringyl to guaiacyl units in regenerated lignin with IL–water treatment.
研究领域:
生物化学
·
材料科学
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DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2017
·
IF 4.811
Yahui Meng,Zhiqiang Pang,Cuihua Dong
It’s challenging to dissolve natural cellulose in most solvents due to its highly ordered crystalline structure. In this paper, we developed an efficient cellulose dissolution system which incorporates solid acid (SA) with 1-butyl-3-methylimidizolium chloride (BmimCl). The results showed that addition of solid acid both Amberlyst ® 15 and Cs x H 3−x PW 12 O 40 could significantly enhance cellulose dissolution in BmimCl, which attributed to the synergistic action of free hydrogen proton from SA and chloride anion in BmimCl on hydroxyl groups of cellulose, and DMF as co-solvent also could facilitate cellulose dissolution in SA/BmimCl. In contrast to BmimCl system, the SA/BmimCl system for cellulose dissolution achieves better efficiency at mild treatment conditions and facile recovery of solvents. In addition, characterization of the regenerated celluloses showed that SA/BmimCl is a non-derivatizing solvent for cellulose, which helps achieve complete dissolution on crystalline cellulose. Attributed to its low cost and environmentally friendliness for biomass processing, SA/BmimCl systems is a promising and effective solvent system.
研究领域:
生物化学
·
材料科学
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产品关联
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2017
·Vol. 41
·期 5
·2090-2097
·
IF 3.269
Dongshun Deng,Yaotai Jiang,Xiaobang Liu
A series of furoate anion-functionized ionic liquids (ILs) were synthesized and applied as new absorbents for SO2. Results showed that these ILs possessed satisfactory performance for SO2 absorption. At 293.15 K, the maximum absorption capacity was 0.69 and 0.24 g SO2 per g P4442[FA] under 1.0 and 0.1 bar, respectively. The SO2 enriched ILs were easily regenerated by bubbling N2 at 343.15 K and recycled five times without obvious loss of absorption performance. The influences of temperature, SO2 partial pressure, and water content in ILs on SO2 absorption performance were systematically explored. The absorption capacity of ILs is discussed from aspects of the structure of cations, anions, and the interaction of cation–anion. The absorption mechanism was analyzed using NMR and FTIR methods. The selectivities of SO2/CO2, SO2/N2 and SO2/O2 were studied and [P4442][FA] achieved relatively high selectivity for SO2 compared to other gases. Present furoate ILs demonstrate potential application as a SO2 absorbent owing to their good performance.
研究领域:
环境科学
·
化学工程
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产品关联
DOI
高影响因子
IRANIAN POLYMER JOURNAL
·
2017
·Vol. 26
·期 3
·205-211
·
IF 1.422
Zhou Min-Jie,He Fang,Wu Hu,Wang Guo-Xiang,Liu Li-Chao,Xu Wenyuan
Fe-mediated photo-induced atom transfer radical polymerization (ATRP) of methyl methacrylate was studied with chlorophyll A as photoredox catalyst in the absence of ligands. This is the first report on photo-induced and FeBr 3 -mediated ATRP. A low-cost and environmentally friendly ATRP is provided in this system. A good linear semi-logarithmic plot of polymerization kinetics is the first-order time conversion, and narrow molecular weight distributions explain the well-controlled behavior. The measured number average molecular weight, M
n,GPC (determined by gel permeation chromatography), is increased with monomer conversion, and it is in good agreement with the theoretical values ( M
n,th ). The effect of FeBr 3 is studied with respect to the polymerization. The values of the resultant PMMA increased with reduced FeBr 3 concentration. In this system, the effect of periodic light/off process has been investigated through chain growth instantly turned on and off in response to the visible light. The polymerization was controllable even though the concentration of Fe-based catalyst was dropped to 4 ppm. The chain-end group having a functionality in the synthesized poly(methyl methacrylate) was characterized by nuclear magnetic resonance spectrometry ( 1 H NMR). However, chain extension experiments show reserved chain-end functionality in the synthesized polymers and further confirm the “living” feature of the Fe-mediated photo-induced atom transfer radical polymerization.
研究领域:
材料科学
·
高分子化学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2017
·
IF 6.216
Jiao Yuan,Meiling Fan,Fangfang Zhang,Yusu Xu,Haolin Tang,Chi Huang,Haining Zhang
Amine-functionalized imidazolium-based poly(ionic liquid) brushes on titanate nanotubes are synthesized using a convenient “grafting through” technique. The carbon dioxide adsorption performance of the synthesized polymer brushes is evaluated using temperature programmed desorption (TPD) process. TPD profiles of the synthesized polymer brushes after carbon dioxide adsorption reveal that carbon dioxide molecules can adsorb on the synthesized polymer brushes through physical adsorption, reaction with 2-position carbon of imidazole rings, and chemical reaction with amine groups. The total carbon dioxide adsorption capacity of the synthesized poly(ionic liquid) brushes with polymer content of 46 wt.% achieves 2.43 mmol g −1 at 25 °C under carbon dioxide partial pressure of 0.2 bar, higher than that of the corresponding free polymer powders (1.28 mmol g −1 ) under the same conditions. The total adsorption capacity decreases to 1.46 mmol g −1 after two TPD adsorption/desorption cycles and it however remains almost constant in the later cycles.
研究领域:
材料科学
·
环境科学
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产品关联
DOI
高影响因子
CELLULOSE
·
2020
·Vol. 27
·期 7
·3889-3902
·
IF 4.21
Zhu Mengni,Cao Qiping,Liu Bingyang,Guo Haoyu,Wang Xing,Han Ying,Sun Guangwei,Li Yao,Zhou Jinghui
Abstract Global air pollution poses a serious risk to human health. Among the variety of types of pollution, inhalable particulate matter (PM 2.5) is proved to be extremely harmful. In this work, a simple method was designed to synthesize a novel air filter, which composed of cellulose acetate and poly (ionic liquids) by using the technique of macromolecular design and electrostatic spinning process. The introduction of poly (ionic liquids) effectively reduced the diameter of fibers and thus obtains nano-fibrous filters. The removal rate of PM 10 and PM 2.5 particle by the filters reached 99.65% and 97.94%, respectively. Furthermore, the filters exhibited excellent antibacterial properties against Escherichia coli and Staphylococcus aureus , and no obvious cytotoxicity was observed in vitro culturing cell. After multiple recycling, the filters still maintained excellent antimicrobial properties and fibrous morphology due to the stable covalent bonds between cellulose acetate and poly (ionic liquids). This is a novel strategy to prepare high-quality air filters, which have great potential applications in air purification. Graphic abstract We fabricated a kind of green electrospinning material with stable antibacterial properties through organic synthesis and molecular design. The introduction of poly (ionic liquids) effectively reduces the diameter of fibers and thus obtains nano-fibrous filters. The removal rate of PM 10 and PM 2.5 particle by the filters reached 99.65% and 97.94%, respectively. Furthermore, the filters exhibit excellent antibacterial properties against E. coli and S. aureus, and no obvious cytotoxicity is observed in vitro culturing cell. After multiple recycling, the filters still maintain excellent antimicrobial properties and fibrous morphology.
研究领域:
环境科学
·
材料科学
·
纳米技术
·
空气质量管理
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产品关联
DOI
高影响因子
Gels
·
2022
·Vol. 8
·期 1
·52
·
IF 4.432
Che Zhao,Chengju Sheng,Chao Zhou
Traditional antibacterial hydrogels have a broad-spectrum bactericidal effect and are widely used as wound dressings. However, the biological toxicity and drug resistance of these antibacterial hydrogels cannot meet the requirements of long-term clinical application. Imidazolium poly(ionic liquids) (PILs) are polymeric antibacterial agents exhibiting strong antibacterial properties, as they contain a strong positive charge. In this study, two imidazolium PILs, namely poly(N-butylimidazolium propiolic acid sodium) (PBP) and poly(N-(3,6-dioxaoctane) imidazolium propiolic acid sodium) (PDP), as high efficiency antibacterial agents, were synthesized by polycondensation reaction. Then, the PILs were compounded with polyethylene glycol (PEG) by a thiol-yne click reaction to prepare injectable antibacterial hydrogels. An in vitro assay showed that the injectable antibacterial hydrogels could not only quickly killEscherichia coli(E. coli) andStaphylococcus aureus(S. aureus), but also had low toxicity for human skin fibroblasts cells (HSFs) and human umbilical vein endothelial cells (HUVECs), respectively. Additionally, the lipopolysaccharide (LPS) inflammation model revealed that the injectable antibacterial hydrogels also had anti-inflammatory effects, which would be advantageous to accelerate wound healing.Keywords:antibacterial agents;imidazolium poly(ionic liquids);injectable hydrogels;anti-inflammatory
研究领域:
材料科学
·
生物医学工程
·
药剂学
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产品关联
DOI
PubMed
高影响因子
Chemical Engineering and Processing-Process Intensification
·
2019
·
IF 3.031
Ya-Zhao Liu,Wei Wu,Yi Liu,Bei-Bei Li,Yong Luo,Guang-Wen Chu,Hai-Kui Zou,Jian-Feng Chen
Desulfurization by ionic liquids (ILs) has attracted wide attention since ILs as green solvents can be recycled after desorption. However, the high viscosities of ILs limit the sulfur dioxide (SO 2 ) absorption in gas-liquid contactors. In this work, a rotating packed bed (RPB) with excellent mass transfer performance was employed for SO 2 removal with caprolactam tetrabutyl ammonium bromide ([CPL][TBAB]) IL. Effects of rotational speed, temperature, liquid flow rate, and gas flow rate on the desulfurization efficiency were systematically studied. By optimization of the solvents, the desulfurization efficiency remains almost unchanged after multiple absorption and regeneration cycles, and the energy consumption during desorption process can also be reduced. These results indicated that the RPB combined with ILs has promising prospects for SO 2 absorption and desorption in sulfuric acid plants.
研究领域:
化学工程
·
环境科学
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产品关联
DOI
高影响因子
COLLOID AND POLYMER SCIENCE
·
2020
·Vol. 298
·期 8
·1013-1021
·
IF 1.536
Li Yuwei,Lian Ruili,Wang Xinmin,Liu Yonglu
Although ionic liquids have been studied as self-assembly media, the aggregation of fluorinated surfactants in ionic liquids has not been fully understood. In this work, the aggregation behavior of the fluorinated surfactant, N-ethylperfluorooctane sulfonamide (N-EtFOSA), in the aprotic ionic liquid, 1-ethyl-3-methylimidazolium ethylsulfate ([C 2 mim][EtSO 4 ]), was studied using surface tension, 19 F-NMR, dynamic light scattering (DLS), and cryo transmission electron microscopy (cryo-TEM). The surface properties and thermodynamic parameters were calculated based on the results of surface tension measurements. It was found that the fluorinated surfactant exhibits a considerable surface activity in aprotic ionic liquids, and its critical micelle concentration (cmc) increases with increasing temperature. In addition, the surface properties indicate that solvophobic interactions are the main driving force for micelle formation. The thermodynamic parameters for micelle formation derived from the temperature dependence of the cmc revealed that micelle formation is an enthalpy-driven process. DLS and cryo-TEM results indicated the presence of nanoscale micelles in the N-EtFOSA + [C 2 mim][EtSO 4 ] system. The results of this work imply that this fluorinated surfactant exhibits a more pronounced surface activity than conventional hydrocarbon surfactants in [C 2 mim][EtSO 4 ].
The self-assembly of fluorinated surfactants in aprotic ionic liquids
研究领域:
化学
·
材料科学
·
界面科学
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DOI
高影响因子
Materials
·
2022
·Vol. 15
·期 20
·7400
·
IF 3.748
Yuhua Zhao,Yujuan Chen,Quanzhou Du,Kelei Zhuo,Lifang Yang,Dong Sun,Guangyue Bai
Ionic liquids (ILs), with their wide electrochemical stable potential window, are promising electrolytes for supercapacitors (SCs). The suitable matching of the ion size and shape of the ILs to the pore size and structure of porous carbon (PC) electrode materials can realize the enhanced capacitive performance of the SCs. Here we report an interesting result: The capacitance of PC-based SCs shows a quasi-sinusoidal relationship with the composition (mass fraction) of the binary IL mixture as the electrolyte. This relationship is also interpreted based on the matching between the pore sizes of the PC materials and the size/shape of various ions of the IL mixture electrolyte. This can provide a new strategy to improve the performance of SCs by formulating a suitable mixture of different ILs to match the carbon-based electrode materials with a special pore size distribution.Keywords:ionic liquid mixture;electrolyte;supercapacitor;porous carbon
研究领域:
材料科学
·
电化学
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产品关联
DOI
PubMed
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2022
·
IF 5.876
Lili Zhang,Hongmei Yang,Huaxin Zhang
In this work, an imidazolyl dicationic ionic liquid was employed as a monomer to construct a novel nitrogen-rich hyper-crosslinked polymer (HCP–N) for the separation of 4-nitrophenol (4-NP) from wastewater. HCP-N was fabricated through a facile one-pot Friedel-Crafts polymerization, using p -dichloroxylene as cross-linking agents, as well as pore structure regulators. The synthesized HCP-N were randomly stacked by lamellar blocks aggregated by nanospheres . The adsorption kinetic data complied well with pseudo-second-order rate equation while the adsorption isothermal equilibriums conformed to the Freundlich model. At the initial concentration of 1000 mg L −1 , the adsorption capacity for 4-NP was up to 437 mg g −1 . The influence of acidity, temperature and coexisted metal ions were investigated systematically. Coexisted Pb 2+ at low concentration (<150 mg L −1 ) could significantly increase the adsorption capacity of HCP-N through complexing-bridging mechanism. The mechanism analyses revealed that hydrogen bonding , electrostatic and π−π interaction contributed together to the adsorption of 4-NP on HCP-N. The adsorbent could be recycled at least five times after the adsorbed 4-NP was separated by ethyl acetate extraction.
研究领域:
环境科学
·
材料科学
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产品关联
DOI
高影响因子
ELECTROCHIMICA ACTA
·
2022
·
IF 7.336
Qiyao Guo,Benlin He,Jin Tan,Qunwei Tang
The high-temperature supercapacitors have attracted growing attentions because the improved charge diffusion kinetics and ion conductivity of the electrolytes at elevated temperatures cause high capacitances. However, the state-of-the-art aqueous and/or anhydrous electrolytes always suffer from water or organic solvent evaporation , poor thermal stability and toxicity. We presented here a wide-temperature window supercapacitor made with an activated carbon electrode, a ceramic membrane separator as well as an electrolyte containing 1-methylimidazolium trifluoromethanesulfonate ([MI m ][OTf]) ionic liquid and ethylene glycol (EG) organic solution of potassium hydroxide (KOH) ([MI m ][OTf]/KOH/EG). By studying the impacts of temperature on capacitance, a maximized specific capacitance of 289 F g − 1 was achieved at 130 °C. Moreover, the champion supercapacitor presented an outstanding charging/discharging stability over 1500 cycles at 130 °C. The high capacitance along with long-term stability suggest that the ionic liquid electrolyte is prospective for wide-temperature window supercapacitors .
研究领域:
材料科学
·
能源存储
✓ 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）