65039-10-3Relevant articles and documents
Separation and recovery of cellulose from Zoysia japonica by 1-allyl-3-methylimidazolium chloride
Li, Wei-Zun,Ju, Mei-Ting,Wang, Yan-Nan,Liu, Le,Jiang, Yang
, p. 228 - 235 (2013)
We investigated the use of ionic liquid (IL) 1-allyl-3-methylimidazolium chloride (AMIMCl) for extracting cellulose from Zoysia japonica by using Fourier transform infrared spectroscopy, nuclear magnetic resonance, scanning electron microscopy and thermogravimetric analysis to analyze the IL and its effects on cellulose extraction. After water pretreatment at 121 °C for several minutes, cellulose extraction rate was 71% under optimized conditions, and the yield of cellulose was >99% by AMIMCl. The effectiveness of AMIMCl as an extraction agent can be attributed to the prevalence of intra- and inter-molecular hydrogen bonding in cellulose. By contrast, hemicelluloses were not recovered by AMIMCl because hemicelluloses in plant cell walls are connected to lignin by covalent bonding. Results also showed that the regenerated cellulose was exactly the same as untreated cellulose, except for the degree of crystallinity.
Task-specific ionic liquid for the depolymerisation of starch-based industrial waste into high reducing sugars
Hernoux-Villière, Audrey,Lévêque, Jean-Marc,K?rkk?inen, Johanna,Papaiconomou, Nicolas,Lajunen, Marja,Lassi, Ulla
, p. 11 - 17 (2014)
Development of a simple route for the catalytic conversion of starch-based industrial waste (potato peels) and potato starch into reducing sugars was investigated in two ionic liquids for comparison - 1-allyl-3-methylimidazolium chloride [AMIM]Cl and 1-(4-sulfobutyl)-3-methylimidazolium chloride [SBMIM]Cl. Over a two hour period, a 20 wt% solution containing up to 43% and 98% of reducing sugars at low temperature in aqueous [SBMIM]Cl was achieved for the starch-based waste and the potato starch, respectively. In addition, the use of microwave and low frequency ultrasound to perform the depolymerisation of the raw starch-based material was explored and compared with conventional heating processes.
Pretreatment of fibre sludge in ionic liquids followed by enzyme and acid catalysed hydrolysis
Holm, Jana,Lassi, Ulla,Romar, Henrik,Lahti, Riikka,K?rkk?inen, Johanna,Lajunen, Marja
, p. 11 - 15 (2012)
Pretreatment of fibre sludge in ionic liquids and enzyme or acid catalysed hydrolysis of fibre sludge is studied. Ionic liquids, i.e. 1-allyl-3- methylimidazolium chloride ([AMIM]Cl) and 1-butyl-3-methylimidazolium chloride ([BMIM]Cl), are used in the pretreatment step. Effect of ionic liquid (IL) pretreatment on the acid and enzyme catalysed hydrolysis of fibre sludge is considered. Cellulose content of fibre sludge is more than 80 wt%, and therefore, reducing sugars obtained as a result of hydrolysis contain mostly glucose. To maximize the yield of reducing sugars during the enzymatic hydrolysis, the combinations of selective enzymes are required. Results also show that the use of ionic liquids in the pretreatment step before acid and enzyme hydrolysis increases significantly the yield of total reducing sugars.
Dissolution of cellulose from AFEX-pretreated Zoysia japonica in AMIMCl with ultrasonic vibration
Liu, Le,Ju, Meiting,Li, Weizun,Hou, Qidong
, p. 412 - 420 (2013)
In this study, 1-allyl-3-methylimidazolium chloride (AMIMCl), an ionic liquid, was synthesized and characterized by a series of test methods. Pretreatment of Zoysia japonica by ammonia fiber expansion (AFEX) was shown to reduce significantly the mass of hemicellulose and lignin in biomass, thereby breaking the lignocellulosic structure. Z. japonica samples pretreated with AFEX showed reasonable solubility in AMIMCl upon ultrasonic treatment. The rate of cellulose regeneration from Z. japonica samples pretreated with AFEX increased with increase in applied power of ultrasonication within a certain power range from 0 to 110 W. The regeneration rate of cellulose from AFEX-pretreated Z. japonica reached a maximum of 97% when the ultrasonic power was 110 W. Fourier transform infrared spectroscopy and nuclear magnetic resonance analyses indicated that the regenerated cellulose was similar to microcrystalline cellulose.
Synthetic, spectroscopic and structural behavior of unsaturated functionalized N-heterocyclic carbene complexes of group 11
González-Abrego, Daniel Omar,Zuno-Cruz, Francisco J.,Carpio-Granillo, Mariana,Andrade-López, Noemí,Cruz-Borbolla, Julián,Martínez-Macias, Claudia,Mendoza-Espinosa, Daniel,Rosales-Hoz, María J.,Leyva, Marco A.,Torres-Lubián, José R.,López-Jiménez, Jorge A.,Jancik, Vojtech,Sánchez-Cabrera, Gloria
, p. 97 - 111 (2017)
A series of unsaturated functionalized silver(I) N-heterocyclic carbenes [{(κC-C7N2H10)AgCl}2] (1a), [{(κC-C8N2H12)2}2Ag][Ag2Cl4] (1b)
Dissolution of feather keratin in ionic liquids
Idris, Azila,Vijayaraghavan,Rana, Usman Ali,Fredericks, Dale,Patti,MacFarlane
, p. 525 - 534 (2013)
Keratin from various livestock industries is currently a waste material that has potential as a source of polyamide polymers that could replace fossil fuel derived materials if processing methods can be developed. In this work we have investigated methods for the dissolution and regeneration of keratin. Dissolution of keratin (from turkey feather) in ionic liquids was conducted under nitrogen at 130 °C for 10 hours. It was found that [BMIM]Cl, [AMIM]Cl and [choline][thioglycolate] could dissolve turkey feather keratin without addition of solvent or other chemicals. A significant percentage of solubility was obtained, up to 45% by weight. A water insoluble fraction was recovered by addition of water to the solution (～50%). The structure and properties of this regenerated, water insoluble fraction were investigated. Compared to the starting material, the regenerated keratin shows structural changes rather than chemical changes within the polypeptide chains. The remaining fraction, consisting of water soluble fragments, was characterised by gel electrophoresis.
Understanding the efficiency of ionic liquids-DMSO as solvents for carbohydrates: use of solvatochromic- And related physicochemical properties
Bioni, Thaís A.,de Oliveira, Mayara L.,Dignani, Marcella T.,El Seoud, Omar A.
, p. 14906 - 14914 (2020/09/23)
The physical dissolution of carbohydrates (cellulose, chitin, and starch),i.e., without the formation of covalent bonds requires the solvent to possess certain physicochemical properties. Concentrating on cellulose, the solvent should act both as a Lewis acid and a Lewis base, and disrupt the present hydrophobic interactions, as the biopolymer exhibits amphiphilic characteristics. The quantification of the relative importance of these physicochemical properties helps in predicting the solvent structures, which are expected to be efficient as cellulose solvents. Ionic liquids (ILs) are extensively used as carbohydrate solvents because they disrupt the intramolecular-, intermolecular-, and hydrophobic interactions within the biopolymer structure, leading to its dissolution. Solvatochromic substances (probes) are especially sensitive to one or more of the above-mentioned biopolymer-solvent interactions. Consequently, they are used to predict and rationalize the solvent efficiency. The solvent parameters (descriptors) most widely employed are empirical polarity,ET(probe), Lewis acidity (SA); Lewis basicity (SB), dipolarity (SD), and polarizability (SP); S refers to the solvent. We synthesized 18 ILs, including derivatives of imidazole, 1,8-diazabicyclo[5.4.0]undec-7-ene, and tetramethylguanidine; the corresponding anions are carboxylates, chloride and dimethylphosphate. We used solvatochromic probes to calculate the descriptors of IL-DMSO (at fixed DMSO mole fraction of 0.6; 40 °C), and correlatedET(probe) with the other descriptors. We also tested the correlations by using a molar volume of the IL (VM) instead of SD, and the Lorentz-Lorenz refractive index functionf(n) of the IL-DMSO mixture instead of SP. The quality of the regression analysis increased noticeably when we limited the ILs correlated with those based on imidazole (13 ILs), and used (VM) andf(n). The regression coefficients showed that SA is the most important descriptor; the solvent empirical polarity is inversely dependent onVM. The value off(n) shows the importance of hydrophobic interactions. By using different probes, we showed that the observed small contribution of SB reflects the steric crowding around the positive nitrogen atoms in some probes. The results obtained help in selecting ILs as solvents for cellulose and other carbohydrates, based on the expected strength of their interactions with the biopolymers. Therefore, using solvatochromism for solvent efficiency screening saves labor and cost.
Direct catalytic conversion of glucose and cellulose
Li, Zhenhuan,Su, Kunmei,Ren, Jun,Yang, Dongjiang,Cheng, Bowen,Kim, Chan Kyung,Yao, Xiangdong
supporting information, p. 863 - 872 (2018/03/05)
Biomass product 5-hydroxymethylfurfural (5-HMF) can be used to synthesize a broad range of value added compounds currently derived from petroleum. Thus, the effective conversion of glucose or cellulose (the major components of biomass) into fuels and chemical commodities has been capturing increasing attention. Previous studies have been extensively focused on a two-step process for producing 5-HMF from glucose or cellulose, i.e., the isomerization of glucose into fructose and then the dehydration of fructose. We herein discovered that heterogeneous sulfonated poly(phenylene sulfide) (SPPS) containing strong Br?nsted acid sites is able to convert glucose and cellulose into 5-HMF with a high yield in ionic liquids (ILs). The optimal activity of glucose conversion to 5-HMF achieves a yield of 87.2% after 4 h reaction at 140 °C. For direct cellulose conversion, a 5-HMF yield of 68.2% can be achieved. The reaction mechanism over the SPPS catalyst in ILs was studied by DFT calculations, and the results indicated that the SO3H group of SPPS plays a crucial role in glucose conversion into 5-HMF, and it acts as a proton donor as a Br?nsted acid and functions as a proton acceptor as the conjugate base. Furthermore, the anions and cations of ILs together with SO3H-SPPS helped in stabilizing the reaction intermediates and transition states, which also resulted in glucose facile conversion into 5-HMF. The new catalyst system highlights new opportunities offered by optimizing the production of 5-HMF directly from glucose and cellulose.
