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Comprehensive Summary: Xylan is the most abundant hemicellulose in nature. As a new type of green organic solvent, ionic liquid shows good preservation ability for the functional groups of hemicellulose. In this paper, a single molecule detection technology based on glass nanopore was established to analyze xylan dissolved in ionic liquid. Arabino‐xylan (AX) and beech xylan (BX) are respectively taken as the representatives of heterogeneous xylan and homogeneous xylan. Firstly, unmodified glass nanopore was used to detect the dissolved xylan in ionic liquid, and then poly(ethylene imine) (PEI) was used to modify the nanopore to change the surface charge in the nanopore and further enhance the interaction between the nanopore and the xylan molecule. It was found that before and after nanopore modification, at negative voltage and low positive voltage, AX didn't generate current blocking signal. On the contrary, BX didn't generate current blocking signal at positive voltage. This phenomenon may be due to the current disturbance driven by electrophoresis and electroosmosis of xylan molecules with weak negative charge. After statistics analysis, the current blocking signal of AX showed that the modified nanopore showed multiple peaks. It indicates that heterogeneous xylan and PEI modified nanopore had stronger interaction. The results show that the nanopore detection technology can show the structural difference of heterogenous branched chain and homogeneous straight chain based on the single characteristic current blocking signal and statistical information, providing a research basis for the structural analysis of water insoluble polysaccharides. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Xylan is the most abundant hemicellulose in nature. As a new type of green organic solvent, ionic liquid shows good preservation ability for the functional groups of hemicellulose. In this paper, a single molecule detection technology based on glass nanopore was established to analyze xylan dissolved in ionic liquid. Arabino‐xylan (AX) and beech xylan (BX) are respectively taken as the representatives of heterogeneous xylan and homogeneous xylan. Firstly, unmodified glass nanopore was used to detect the dissolved xylan in ionic liquid, and then poly(ethylene imine) (PEI) was used to modify the nanopore to change the surface charge in the nanopore and further enhance the interaction between the nanopore and the xylan molecule. It was found that before and after nanopore modification, at negative voltage and low positive voltage, AX didn't generate current blocking signal. On the contrary, BX didn't generate current blocking signal at positive voltage. This phenomenon may be due to the current disturbance driven by electrophoresis and electroosmosis of xylan molecules with weak negative charge. After statistics analysis, the current blocking signal of AX showed that the modified nanopore showed multiple peaks. It indicates that heterogeneous xylan and PEI modified nanopore had stronger interaction. The results show that the nanopore detection technology can show the structural difference of heterogenous branched chain and homogeneous straight chain based on the single characteristic current blocking signal and statistical information, providing a research basis for the structural analysis of water insoluble polysaccharides. [ABSTRACT FROM AUTHOR]

The degradation of 1-butyl 3-methyl imidazolium chloride (BMIMCl) ionic liquid (IL) by Fenton oxidation has been studied. The optimization of operating parameters for maximum degradation of BMIMCl has been carried out using the Central Composite Design (CCD) of Response Surface Methodology (RSM). The three independent input parameters selected were the dosage of Hydrogen Peroxide (H2O2), the dosage of iron (Fe2+), and the pH of the output or response selected was Total Organic Carbon (TOC) removal efficiency. Experiments were carried out according to the experimental design provided by CCD. For TOC Degradation, the model's R² and R² adj correlation coefficients between experimental and model-predicted values were 0.9769 and 0.9561, respectively. This indicates a satisfactory correlation of experimental results with model-predicted values. The optimum values of operating parameters for maximum degradation were found to be H2O2=307 mM (X1), Fe2+=1.1 mM (X2), and (pH)=3.3 (X3), for a reaction time of 120 min. For these operating parameters, the experimental result for TOC removal efficiency was found to be 72.89% as compared to the model-predicted value of 73.67%. These results indicate that the values were closely correlated with each other and thus the model was validated satisfactorily. Overall, the results indicate that the BMIMCl ionic liquid can be effectively degraded by the Fenton oxidation process. [ABSTRACT FROM AUTHOR]

The possibility of using microchannel flow reactors to obtain the kinetic and technological parameters of the synthesis of 1-butyl-3-methylimidazolium chloride (BMIMCl) ionic liquid is demonstrated for the reaction of 1-methylimidazole (MIm) with 1-chlorobutane with no solvents. BMIMCl is produced with high selectivity and specific output in a microchannel flow reactor at temperatures of 120–180°C a contact time of 2–45 min, and a pressure of 20 bar. A positive result is obtained, due to the laminar profile of the flow and a uniform distribution of the reagents concentration over the microchannel cross section. Studying the kinetics of the process in a microchannel flow reactor reveals a shift of the reaction to the mode of diffusive inhibition at temperatures above 150°C. The kinetic data obtained for BMIMCl synthesis are used to develop ways of producing 1-ethyl-3-methylimidazolium and 1-hexyl-3-methylimidazolium chlorides (EMIMCl and HMIMCl, respectively) under the conditions of a microchannel flow reactor. The approach proposed in this work is of interest in developing flow and periodic facilities for the low-tonnage production of dialkylimidazolium, ammonium, and pyridinium salts via quaternization of the corresponding alkyl chlorides and nitrogen-containing bases. [ABSTRACT FROM AUTHOR]

In this study two imidazole-based Ionic liquids, 1- butyl -3 - methyl -1 - Imidazolium chloride (BMIMCl) and 1- butyl -3 - Methyl Imidazolium Methyl sulfate ([BMIM][MeSo4]), were used to dissolve wood flour, cellulose and CMP pulp. The overall evaluation indicates the inability of ([BMIM][MeSo4]) in full dissolution of lignocellulosic materials and sample treatment with this solvent was lead to water soluble degradation products. However, dissolution trials using BMIMCl was able to dissolve Lignocellulosics. Density, clarity, water absorption and thickness swelling of regenerated cellulose films were significantly higher than that of CMP and wood flour, and CMP, higher than wood flour. Also, cellulose film have the lowest water vapor permeability compared to wood flour and CMP. Tensile strength, Young's modulus and strain at breaking point of cellulose film were significantly higher than the CMP and wood flour samples.

Simple approach to prepare various sizes of YF 3 :YbEr nanocrystals in large quantities and their up-converting abilities dependent on preparation times and sodium content are described in this paper. Ionic liquid bmimCl was used in the role of a solvent and NaBF 4 as a fluorination agent. Prepared nanocrystals were characterized by XRD, TEM and up-conversion measurements. The method is suitable for preparation of large quantities of nanocrystals and could be easily adapted and used for relevant important pharmaceutical applications. [ABSTRACT FROM AUTHOR]

Fabricating an aqueous ionic liquid (IL) for deconstruction and dissolution of lignocellulose is attractive because addition of water could reduce the cost and viscosity of the solvent and improve the biomass processing, but the solvating power of the IL is usually depressed in the presence of water. In the present study, an aqueous IL consisting of 1-butyl-3-methylimidazolium chloride (BmimCl), water, and lithium chloride was fabricated for efficient deconstruction and dissolution of lignocellulose (bamboo). The dissolution of cell wall components (cellulose, lignin, and hemicelluloses) in the aqueous IL was investigated. The results indicated that the presence of water significantly reduced the solvating power of BmimCl; For example, 11.5 % water decreased the dissolution of bamboo in BmimCl from ~97 to ~53 %. Dissolution of cellulose and lignin was specifically depressed. However, addition of lithium chloride was able to improve the tolerance of BmimCl to water and enhance the deconstruction and dissolution of biomass in BmimCl with high water content. It was found that approximately 80 % bamboo could be dissolved in solvent consisting of 45 wt% BmimCl and 55 wt% LiCl·2HO (25 wt% overall water content in the solvent). In particular, lignin and hemicelluloses were selectively dissolved by 96 and 92 %, respectively. The undissolved residue was predominantly composed of cellulose (~86 %) with a small amount of lignin (<5 %). BmimCl-LiCl-HO is a promising and effective solvent system with low cost and viscosity for biomass processing. [ABSTRACT FROM AUTHOR]

1-Butyl-3-methylimidazolium chloride (BmimCl), an imidazolium-based ionic liquid, is considered the representative emerging persistent aquatic pollutant, and its environmental toxicity has attracted a growing concern. However, most of the investigations focused on monocultures or a single organism, with little information available on the complex syntrophic consortium that dominates the complex and successional biochemical processes, such as anaerobic digestion. In this study, the effect of BmimCl at environmentally relevant levels on glucose anaerobic digestion was therefore investigated in several laboratory-scale mesophilic anaerobic digesters to provide such support. Experimental results showed that BmimCl at 1-20 mg/L inhibited the methane production rate by 3.50-31.03%, and 20 mg/L BmimCl inhibited butyrate, hydrogen, and acetate biotransformation by 14.29%, 36.36%, and 11.57%, respectively. Toxicological mechanism studies revealed that extracellular polymeric substances (EPSs) adsorbed and accumulated BmimCl through carboxyl, amino, and hydroxyl groups, which destroyed the EPSs' conformational structure, thereby leading to the inactivation of microbial cells. MiSeq sequencing data indicated that the abundance of Clostridium&#95;sensu&#95;stricto&#95;1 , Bacteroides , and Methanothrix decreased by 6.01%, 7.02%, and 18.45%, respectively, in response to 20 mg/L BmimCl. Molecular ecological network analysis showed that compared with the control, the lower network complexity, fewer keystone taxa, and fewer associations among microbial taxa were found in the BmimCl-present digester, indicating the reduced stability of the microbial community.

The removal of ionic liquid (1-butyl-3-methyl imidazolium chloride: BMImCl) was studied from aqueous solution by raw bentonite, acid-activated bentonite and organic-modified bentonite. These types of bentonite sample were characterized by FT-IR, TGA and XRD. The effects of contact time, BMImCl initial concentration, pH, ionic strength, and humic acid on the removal of BMImCl were investigated via batch adsorption experiments. The adsorption kinetics models were applied to predict the adsorption constants, and the kinetic data indicated that the pseudo-second-order model gave a better fit. Furthermore, the Langmuir, Freundlich and Temkin isotherms models were also introduced to describe adsorption process in order to obtain possible mechanism of the removal. The applied isotherms models demonstrated that the adsorption data of acid-activated bentonite samples were well described by Temkin adsorption isotherm, and the isotherm model of organic-modified bentonite was Langmuir adsorption isotherm. The adsorption experiments indicated that these bentonite samples might be applied in repair of soil and water contaminated by ionic liquids. [ABSTRACT FROM AUTHOR]

Abstract: With potassium hydroxide (KOH) as catalyst, hydroxypropyl guar gum (HPG) was successfully prepared under homogenous conditions in an ionic liquid 1-butyl-3-methylimidazolium chloride (BmimCl). The value of degree of molar substitution (MS) of HPG, which was determined by means of 1H NMR, was easily controlled by varying the mass ratio of propylene oxide (PO) to guar gum (GG). The distribution of hydroxypropyl moieties among the seven hydroxy groups in HPGs was investigated by NMR and the results indicated that the homogeneous reaction preferentially substituted at the C3 mannosyl residues in guar gum which was quite different from the heterogeneous reaction where substitution mostly occurred at C6 verage number of hydroxypropyl units per OH substitution of HPGs with MS value of 0.20, 0.37 and 0.60 was 1.82, 1.42 and 1.76, respectively. [Copyright &y& Elsevier]

Abstract: Lanthanum fluorides are important materials for their optical properties especially in the form of thin film or nanoparticles. In this paper we describe preparation of LaF3 nanoparticles by simple one-step synthesis. Ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate (bmimPF6) was used both as fluorination agent and solvent in the first preparation method and KPF6 (fluorination agent) dissolved in ionic liquid 1-butyl-3-methylimidazolium chloride (bmimCl) in the second synthesis procedure. In both cases liquid La(NO3)3 was used as the source of lanthanum. Reaction was performed at 200°C for 90min. Obtained white powders were washed by distilled water and methanol, dried on air and analyzed by Nanophox (particle size distribution), X-ray diffraction and by SEM and HRTEM. Nanoparticles of pure LaF3 were prepared and their size was estimated from X-ray pattern to be 11.0 and 11.6nm in the first and second case, respectively. Sizes of nanocrystals were conformed by HRTEM. It was observed by SEM that nanoparticles tend to form irregular aggregates and their average size was estimated by Nanophox. Although nanocrystals prepared by both ways are of very similar size, the sizes of their aggregates differ significantly (730nm from bmimPF6 vs. 3600nm from KPF6 in bmimCl). [Copyright &y& Elsevier]

Abstract: Cerium trifluoride have great potential in material applications for luminescent materials, composite materials or ionic conductors especially in the form of nanoparticles and nanoobjects. In this work, nanoparticles of CeF3 were prepared by simple one pot reaction of ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate (bmimPF6) with CeO2 and by reaction of CeO2 with KPF6 in ionic liquid 1-butyl-3-methylimidazolium chloride (bmimCl). Prepared nanoparticles were analyzed by XRD and SEM analysis. Average diameter of prepared nanoparticles resulting from Sherrer formula is 12nm. Nanoparticles did not form ordered agglomerates and could be used in the form of separate nanoparticles which are desired in some applications. [Copyright &y& Elsevier]

Abstract: This paper reports hydrogen (H2) yield and reaction rate measurements of ammonia borane (AB) thermolysis in the neat form as well as facilitated by the presence of an ionic solvent, 1-butyl-3-methylimidazolium chloride (bmimCl). The measurements were conducted at various temperatures between 85 and 120°C under quasi-isothermal conditions. The details of fast hydrogen evolution at the initial stage of the thermolysis process were captured for the first time. The presence of bmimCl led to significant increases in both the rate and the amount of hydrogen released, compared to the corresponding quantities at identical temperatures for neat AB thermolysis. Measurements reported in the literature are in qualitative agreement with this observation but lack the time resolution necessary for the quantitative comparisons. At 120°C, the measured gravimetric H2 storage capacity from the neat AB thermolysis was 9.9wt% (material base) and that from the AB/bmimCl mixture (80/20wt%) thermolysis was 11.2wt%. Also, the reaction rate of the thermolysis of AB/bmimCl mixture (80/20wt%) was twice as fast as that of the neat AB thermolysis at this temperature. In the bmimCl (20wt%) aided AB thermolysis, a significant increase in the H2 yield occurred at temperatures over 107°C. [Copyright &y& Elsevier]

[Display omitted] • Dahlia flower-like Co 3 O 4 (DFCoO) is fabricated and comprised of nano-filaments. • DFCoO shows an activity than Co 3 O 4 NP to activate MPS for degrading BMIM. • DFCoO is also reusable for activating MPS to degrade BMIM over 5 cycles. • BMIM degradation mechanism by DFCoO + MPS is elucidated by radical species. • Degradation pathway by this DFCoO + MPS is also revealed by intermediates. As the imidazolium-based ionic liquid (IL), 1-Butyl-3-methylimidazolium chloride (BMIMCl), is increasingly employed in various applications, release of BMIM cation into the environment has posed serious threats on aquatic ecology. Thus, it is imperative to eliminate BMIM from water, and, among various techniques for eliminating BMIM, chemical oxidation is the most effective technique. Nevertheless, studies of using SO 4 −-based chemical oxidation methods for degrading BMIM are still very limited; thus this study aims to develop an effective SO 4 −-based chemical oxidation process for degrading BMIM. As monopersulfate (MPS) is employed as a source of SO 4 −, a special cobalt (Co)-based catalyst is proposed and developed here by fabricating Co 3 O 4 into a unique Dahlia flower-like morphology. Such a Dahlia flower-like Co 3 O 4 (DFCoO) not only can exhibit the flower configuration, but also its floral petal components can consist of many filament-like Co 3 O 4 nanostructures, making this DFCoO possess several advantageous properties over the conventional Co 3 O 4 nanoparticle (NP), including higher redox activity, more reactive surface, higher surface area and larger pore volume. Thus, DFCoO shows a much higher catalytic activity than Co 3 O 4 NP to activate MPS for degrading BMIM. A higher MPS dosage and reaction temperature also enhance BMIM degradation by DFCoO + MPS. DFCoO is reusable for activating MPS to degrade BMIM over multiple cycles. BMIM degradation mechanism and pathway by this DFCoO + MPS is also elucidated by identifying radical species and degradation intermediates. The findings of this study offer an useful approach for developing an advantageous catalyst for sulfate-based degradation of BMIMCl. [ABSTRACT FROM AUTHOR]

We report a novel chitosan derivative, chitosan-ionic liquid (CS-IL) conjugation for anion adsorption. Specifically, CS-IL conjugation was synthesized through the reaction of amino groups of chitosan with carboxylic groups of 1-carboxybutyl-3-methylimidazolium chloride. Due to the amphiphilic structure, CS-IL conjugation could self-assemble into nanoparticles in distilled water. This novel chitosan derivative revealed good anion adsorption performance, and the adsorption capacity of Cr2O7(2-) and PF6(-) was 0.422 mmol/g and 0.840 mmol/g, respectively. The adsorption of Cr2O7(2-) and PF6(-) could be improved at low pH, which was ascribed to the adsorption of protonated NH2 on chitosan. Importantly, the chitosan derivative would aggregate in the water after the adsorption and could be easily separated. The properties enable CS-IL conjugation to be used as a novel anion adsorbent for wastewater treatment., (Copyright © 2013 Elsevier B.V. All rights reserved.)