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In the present work, we obtained density (ρ123), speed of sound (u123), excess molar volume (Vm123E), and deviation in isentropic compressibility (Δks123) for ternary mixtures of {[BMIM][BF4] (x1) ...

Thermophysical properties of 1-butyl-3-methylimidazoliumtris(pentafluoroethyl) trifluorophosphate, [C4mim][(C2F5)3PF3] (CAS RN 917762-91-5) ionic liquid, were measured in the temperature range T = ...

Different types of zeolites could be synthesized changing the variables in the synthesis process. This paper studies the stirring effect on zeolites synthesis at different Si/Al molar ratios (1, 8, 20, 50 and 120) using the ionic liquid 1-butyl-3-methylimidazolium chloride (BMI.Cl) as structure-direct agent. The results suggest that the ionic liquid BMI.Cl would be a highly effective directing agent for the crystallization of zeolites type A, ZSM-5, Beta and ZSM-35. The stirring effect on compositional and morphological parameters seems to be significant. Therefore, ternary composition diagrams were plotted for the static and stirring conditions, showing the influence of stirring on the composition and morphology of the generated materials. It was possible to verify, in the ternary diagrams, the conditions for obtaining the pure ZSM-5 and ZSM-35 zeolites, as well as the different morphologies found for the same regions, when the zeolites were synthesized under static and stirring conditions. It is also observed that the zeolites ZSM-35 and Beta show a greater amount of Al2O3 (4 mol% and 1.6 mol%) only when the reaction is carried out under stirring conditions.

The aluminum is electrodeposited from an ionic liquid comprising a eutectic mixture of 1-butyl-3-methylimidazolium chloride (BMIC) and aluminum chloride (AlCl3) at the AlCl3 mole fraction of 0.667 (molar ratio of 1:2). The electrochemical behavior of chloroaluminate species in the ionic liquid (IL) is investigated by the chronoamperometry (CA) technique at different temperatures. The diffusion coefficients (D) of Al2Cl7 – anion species in BMIC-AlCl3 IL are calculated at various temperatures based on the chronoamperometric method. The calculated number density of nucleation of Al deposits are 0.7 × 1010, 1.0 × 1010, and 1.4 × 1010 m-2 at 363 K with the applied potentials of -1.7, -1.75, and -1.8 V versus Pt, respectively. The scanning electron microscopy (SEM) result indicated that the calculated data is comparable to the experimental electrodeposition data. In addition, the rate of nucleation was also investigated during the electrodeposition experiment.

The electrochemical behavior of titanium-chloroaluminate anion species in Lewis acidic 1-butyl-3-methylimidazolium chloride (BMIC)-aluminum chloride (AlCl3) ionic liquid (IL) electrolyte with 0.667 AlCl3 mole fraction is investigated at 383K by cyclic voltammetry (CV), chronoamperometry (CA), and chronopotentiometry (CP). The effect of scan rate on peak potential and peak current, constant current density, constant applied potential, and the electrolyte temperature are discussed. The redox reaction of the Ti2+/Ti0 deposition from titanium hepta-chloroaluminate ([Ti(Al2Cl7)4]2−) anions is a reversible process with a 2-electron transfer while that of Al3+/Al0 deposition from hepta-chloroaluminate ([Al2Cl7]−) anions is quasi-reversible with 3-electron transfer. The cyclic voltammograms indicated that the reduction of [Al2Cl7]− and [Ti(Al2Cl7)4]2− species to corresponding Al and Ti forms is a diffusion-controlled phenomenon. The diffusion coefficients (D) of the anion-species in BMIC-AlCl3 IL determined at 383 K using CV and CP methods are 9.74 × 10−10 m2 s−1 and 6.36 × 10−10 m2 s−1, respectively.

Thermogravimetric analysis (TGA) is used to study the thermophysical properties of three ionic liquids with 1-butyl-3-methylimidazolium cation. The temperatures and enthalpies of melting and thermal decomposition are determined, and the IR spectra of gaseous products of thermal decomposition are studied. The relationship between the structure of compounds and their thermochemical characteristics is considered.

Lignocellulosic materials are generally considered hydrophilic due to the high density of hydroxyl groups. The use of lignocellulosic materials in hydrophobic systems thus require surface modification. Therefore, in this study, cellulose (MCC) and sawdust (SD) have been pretreated with ionic liquid, 1-butyl-3-methylimidazolium chloride (BMIMCl) prior to surface modification with cationic surfactant, hexadecyl trimethylammonium bromide (CTAB). The effect of BMIMCl pretreatment prior to surface modification has been investigated. Crystallinity, functional group changes, morphology and thermal stability of the sawdust and cellulose upon BMIMCl pretreatment and surface modification have been studied using x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and thermogravimetric Analysis (TGA). XRD results showed that the structure of lignocellulosic materials became more amorphous upon pretreatment with BMIMCl. FTIR results indicated that the modification of lignocellulosic is more efficient in BMIMCl-pretreated samples. Percentage of decomposition is higher for the BMIMCl-pretreated and CTAB modified samples.

We investigated the stability of the liquid phase of 1-butyl-3-methylimidazolium iodide (hereafter abbreviated as [C4mim][I]) up to 16.7 GPa at room temperature. We observed a peculiar phase transition behavior in the [C4mim][I] sample. In particular, a glassy state was formed at ∼1.3 GPa; however, the reddish-brown precipitate was formed probably due to concentrated I3- or I2- species that were formed above 12 GPa; [C4mim][I] showed a pressure-induced partial crystallization from the glassy state. We concluded that the conformation of [C4mim]+ is essential in iterative modulation to control the environmental formation of iodide precipitate.

Direct dynamics trajectory simulations were carried out for the NO2 oxidation of EMIM+DCA-, which were aimed at probing the nature of the primary and secondary reactions in the system. Guided by tr...

Driven by regulatory requirements to reduce the content of sulphur in fuels, the demand to find an alternative process to hydrodesulphurization is on the rise. In this study, experiments were conducted for the removal of sulphur compound (present as benzothiophene or BT) with concentration of 2000 ppm in the model oil (present as n-dodecane or n-C12) using 1-butyl-3-methylimidazolium tricyanomethane ([bmim][TCM]) as the extractant. The effects of stirring speed, extraction time and water content on the extraction efficiency were investigated. In the end, the loading factor of the [bmim][TCM] is also discussed where it can be concluded that, more than one mole of [bmim][TCM] may interacted with one mole of BT during extractive desulphurization process.

Nickel coating was obtained by potentiostatic electrodeposition in 1-butyl-3-methylimidazolium diethylphosphate ionic liquid without any additive. Further, cyclic voltammetry (CV) tests were used to investigate the electrochemical behaviour of Ni2+ in the ionic liquid, revealing that the electrodeposition of nickel in this ionic liquid is an irreversible process. It was revealed that the diffusion of Ni2+ is a rate-determining step in the electrodeposition process. Further, the influence of dissolved water and applied voltage on electrodeposition were also studied using scanning electron microscopy (SEM).

Alkali lignin is a component of the waste black liquor produced by the paper-making industry that is difficult to degrade. In recent years, the biological activities of lignin, such as free-radical scavenging and antioxidant capacity, have received increasing attention. Here, we prepared H3PW12O40/ZrO2 and used this catalyst together with the ionic liquid 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) as a double-effect catalyst for the degradation of alkali lignin. Single-factor and orthogonal tests showed that the best degradation conditions were as follows: reaction time, 2 h; reaction temperature, 100 °C; mass ratio of H3PW12O40/ZrO2 to lignin, 1:4; and substrate concentration, 2.5%. The phenolic hydroxyl group content of the lignin degradation product increased by 231.2% and the total hydroxyl group content increased by 337.1% when the double-effect catalyst was used rather than [BMIM]Cl alone. Analysis by gel permeation chromatography showed that both the weight-average molecular weight and the number-average molecular weight of the product were reduced and that the lignin was degraded into small-molecular-weight compounds by the macromolecule. The product after the catalytic degradation of lignin showed a markedly increased antioxidant capacity, which was similar to that of the commercial antioxidant, 2,6-ditert-butyl-4-methylphenol. The study opens up a new direction for the better utilization of lignin.

FCT/MEC (Portugal), through "Investigador FCT 2014" (IF/00190/2014 to A.B.P and IF/00210/2014 to J.M.M.A.),; Projects PTD C/EQU-EQU/29737/2017; PTDC/QEQFTT/32,89/2014; IF/00210/2014/CP1244/CT0003. This work was also supported by the Associate Laboratory for Green Chemistry LAQV (financed by national funds from FCT/MCTES (UID/QUI/50006/2019)) and cofinanced by the ERDF under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007265). Mixing ionic liquids (as well as mixing an inorganic salt in an ionic liquid) constitutes an easy, elegant methodology for obtaining new ionic materials. In this study, 3 ionic liquids (ILs) sharing a common cation were synthesized and mixed in 9 different proportions giving rise to 27 binary mixtures. Specifically, 1-butyl-3-methylimidazolium nitrate, [C4C1Im][NO3], 1-butyl-3-methylimidazolium chloride, [C4C1Im]Cl, and 1-butyl-3-methylimidazolium methanesulfonate, [C4C1Im][CH3SO3], were synthesized and characterized. They all share 1-butyl-3-methylimidazolium as the common archetypal cation. None of them (or any of their binary mixtures) is liquid at room temperature (T = 298.15 K), and two of them are only in the liquid state above temperatures of 343-353 K. Despite belonging to commonly used families of ILs, their handling and the study of their liquid properties (neat and mixtures) have become particularly difficult, mainly because of their tendency to solidify and their high viscosity (caused by hydrogen-bonded networks). The main goal of this work is to evaluate the thermal, dynamic, and volumetric properties of these compounds and their mixtures as well as the solid-liquid equilibria of their binary mixtures. Thermal properties, such as melting and glass-transition temperatures, were determined or calculated. Therefore, both density and viscosity have been measured and were used for the calculation of the isobaric thermal expansion coefficient, molar volumes, excess molar volumes, and viscosity deviations to linearity. authorsversion published

Ionic liquids (ILs) have been reported to have an enhanced absorption capacity for SO2 compared to that of traditional molecular solvents. This work evaluated the effect of water content in a 1-but...

Solubility data of carbon dioxide (CO2) in 1-ethyl-3-methylimidazolium trifluoromethanesulfonate [EMIM][TFO] at T = (273.15 to 413.15) K and in 1-butyl-3-methylimidazolium trifluoromethanesulfonate...

The thermal conductivities of 1-butyl-3-methylimidazolium l-tryptophan ([BMIM][l-trp]), water, ethanol, [BMIM][l-trp] + water, [BMIM][l-trp] + ethanol, water + ethanol, and [BMIM][l-trp] + water + ...

An aqueous blend of 1-butyl-3-methylimidazolium tetrafluoroburate ([Bmim][BF4]) + piperazine (PZ) was proposed in this work. Density and viscosity of the aqueous blend were measured and correlated at (293.15–333.15) K and atmospheric pressure. Performance of CO2 absorption into the aqueous blend was evaluated. It turned out that PZ mass fraction slightly influenced on the density and viscosity, being linear with them. Temperature significantly affected the viscosity. The calculated values are in good agreement with the experimental values. The main factors affecting the CO2 loading of the aqueous blend were PZ mass fraction, gas CO2 mole fraction and temperature. The average absorption rate of the aqueous blend was the biggest in the aqueous [Bmim][BF4], PZ and [Bmim][BF4]/PZ, and much higher than that of the former two. The performance of the aqueous [Bmim][BF4]/PZ with low PZ mass fraction was better than that with high PZ mass fraction. It demonstrated that the aqueous blend of [Bmim][BF4]/PZ is a good absorbent of CO2.

Various percentages of 1-butyl-3-methylimidazolium iodide (BMII) from 1 to 5 wt.% were introduced into the most efficient N-phthaloylchitosan (PhCh) based GPEs with lithium iodide (LiI)-tetrapropylammonium iodide (TPAI) binary salts system. Addition of BMII to the PhCh-EC-DMF-TPAI-LiI-I2 electrolyte improved the DSSC efficiency. The value of the efficiency enhanced to 6.69 % with the JSC of 16.53 mA cm‾2, VOC of 0.62 V and fill factor of 0.65.

Since most of the literature alternatives used to produce the ionic liquid 1-butyl-3-methylimidazolium acetate [Bmim][Ac] are very slow and require different solvents, we have used in this work a new process to produce the [Bmim][Ac] by the reaction of the ionic liquid 1-butyl-3-methylimidazolium chloride [Bmim]Cl with silver acetate (AgAc) where silver chloride (AgCl) precipitates as a by-product. The genuine experimental work and kinetic analyses presented here indicate that the reaction rate constant k = 7.67x1012 e(−79.285/RT). That is, the Arrhenius constant ko = 7.67x1012 L/mol.s and the activation energy Ea = 79.285 kJ/mol. The very high value of the Arrhenius constant indicates that the reaction of [Bmim]Cl with silver acetate to produce [Bmim][Ac] and silver chloride is extremely fast.

Transient batteries play a pivotal role in the development of fully autonomous transient devices, which are designed to degrade after a period of stable operation. Here, a new transient separator-electrolyte pair is introduced for lithium ion batteries. Cellulose nanocrystals (CNCs) are selectively located onto the nanopores of polyvinyl alcohol membranes, providing mobile ions to interact with the liquid electrolyte. After lithiation of CNCs, membranes with electrolyte uptake of 510 wt%, ionic conductivities of 3.077 mS·cm–1, electrochemical stability of 5.5 V versus Li/Li+, and high Li+ transport numbers are achieved. Using an organic electrolyte, the separators enable stable Li metal deposition with no dendrite growth, delivering 94 mAh·g–1 in Li/LiFePO4 cells at 100 mA·g–1 after 200 cycles. To make the separator-electrolyte pair transient and non-toxic, the organic electrolyte is replaced by a biocompatible ionic liquid. As a proof of concept, a fully transient Li/V2O5 cell is assembled, delivering 55 mAh·g–1 after 200 cycles at 100 mA·g–1. Thanks to the reversible Li plating/stripping, dendrite growth suppression, capacity retention, and degradability, these materials hold a bright future in the uptake of circular economy concepts applied to the energy storage field., Advanced Functional Materials, 31 (33), ISSN:1616-3028, ISSN:1616-301X

Ionic liquids (ILs) based on 1-butyl-3-methylimidazolium (bmim) cation have proved to be promising solvents for the fractionation of plant biomass with the production of cellulose and lignin. This study deals with the characterization of lignins isolated from coniferous (spruce) wood using [bmim]OAc and [bmim]MeSO4 ionic liquids and their binary mixtures with DMSO (80:20). Molecular weight distributions, functional composition, and structural features of IL lignins were studied by size-exclusion chromatography, NMR spectroscopy (1D and 2D) and atmospheric pressure photoionization high-resolution mass spectrometry. It was shown that the interaction of ILs with lignin leads to significant chemical changes in the biopolymer, a decrease in the degree of polymerization and in the content of free phenolic hydroxyl groups due to alkylation, the disappearance (in the case of [bmim]OAc) of carbonyl groups and a significant destruction of &beta, O-4 bonds. The chemical reactions between lignin and 1-butyl-3-methylidazolium cation with covalent binding of ionic liquids or products of their decomposition is evidenced by the presence of a large number of nitrogen-containing oligomers in IL lignins.

1-Butyl-3-methylimidazolium hydrogen sulfate ([BMIM][HSO4]) as a non-halogenated ionic liquid (IL) was used for the synthesis of 3,4-dihydropyrimidin-2(1H)-ones and thiones or 2-selenoxo DHPMs in a Biginelli type multi-component reaction. By using this ionic liquid, the reaction time was significantly reduced and the products were obtained in good to high yields. Also, in this method, the synthesis of novel 2-selenoxo DHPMs is introduced in the presence of this ionic liquid and their structures were determined by 1H and 13C NMR, FT-IR, and Elemental analysis.

The cation structural changes of two 1-butyl-3-methylimidazolium halides, [BMIM]Cl and [BMIM]Br, are investigated by in situ Raman spectroscopy, infrared spectroscopy, and synchrotron X-ray diffraction as a function of hydrostatic pressure. The [BMIM]+ cations of [BMIM]Cl take the TT conformation under ambient conditions, undergo significant changes at 3.4 GPa, which is related to the potential formations of some new cation conformations, and take another conformation from 6.8 to 35.6 GPa. Correspondingly, crystalline [BMIM]Cl has a structure transition at 3.4 GPa, originating directly from the cation conformational changes. The [BMIM]+ cations totally transform into the GT conformer, if the diamond anvil cell-loaded sample is treated at 423 K for 12 h in a furnace before being cooled down to room temperature. It is the first time to observe the complete conformational transition from one conformer (TT) to another (GT) for the [BMIM]+ salts in experiments. The cations preserve the GT conformation as press...

A comparative study of the molecular-mass characteristics and rheological properties of solutions of silk fibroin in 1-butyl-3-methylimidazolium chloride and acetate was made.

Additives like ionic liquids (ILs) have proven to be excellent materials useful in improving the electrospinnability and conductivity of both synthetic and biopolymers. The aim of this study is to ...

The density and speed of sound data were determined for various binary compositions of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Bmim][NTf2]) (1) and 2-methoxyethanol (2) at different temperatures. These data were utilized to calculate different acoustic and thermodynamic parameters. The variations in these parameters were analyzed to know the behavior of molecular interactions present between the chemical species. The Redlich–Kister equation was used to estimate the deviation between the calculated and experimental excess values. Furthermore, experimental FT-IR analysis was also used to study the interactions between the chemical species.