Synthesis Of Ionic Liquids Research Articles

Positive electrode material in lead-acid car battery modified by protic ammonium ionic liquid

Abstract The aim of the presented study was to develop a feasible and technologically viable modification of a 12 V lead-acid battery, which improves its energy density, capacity and lifetime. The proposed solution promotes the addition of a protic ammonium ionic liquid to the active mass of the positive electrode in the lead-acid battery. The experiments included the synthesis and characterisation of several protic ammonium-based ionic liquids, which differed in terms of the length of the side chain in the cation. A three-stage procedure of the battery test was proposed. First, a laboratory model with a Pb-Ca-Sn alloy as a working electrode and ionic liquids as additives to the electrolytes enabled the selection of the best modifier. Addition of the best-studied ionic liquid, N,N-dimethylhexadecylammonium sulfate, suppressed the corrosion of current collector material by approx. 70% and increased the overpotential of hydrogen evolution reaction. Afterwards, tests on 2 V model lead-acid cells were carried out to compare the various concentrations of the ionic liquid in the active mass. Finally, tests on 12 V lead-acid batteries with 0.5% of protic ionic liquid were performed to evaluate the final influence on the full, industrial product.

MICROWAVE-ASSISTED IONIC LIQUID CATALYZED ONE-POT SYNTHESIS OF HEXAHYDROQUINOLINE DERIVATIVES

Ionic liquid catalyzed one-pot synthesis of hexahydroquinoline derivatives using substituted aryl aldehydes , dimedone, malononitrile and ammonium acetate has been described under microwave irradiation. The protocol has been utilized mild reaction conditions, excellent yield, shorter reaction time and simple workup procedure. The synthesized derivatives were obtained in 80-95% yields and were characterized by IR, 1 H NMR, and mass spectra.

Thermophysical properties of 4-dimethylaminopyridine based ionic liquids

In this study, a molecular simulation (Gaussian03) was used to analyze the chemical structure of 4-dimethylaminopyridine (DMAP) to investigate its use for the synthesis of ionic liquids (ILs). Based on DMAP, a series of new ILs was prepared and characterized by fourier transform infrared spectroscopy (FT-IR), 1H nuclear magnetic resonance (1H-NMR), thermogravimetric analysis (TGA), and differential scanning calorimeter (DSC). The density data of the studied ILs were measured from 328.15 K to 358.15 K, p = 0.101 MPa. It is shown that density decreases with an increase in the temperature and the alkyl chain length of cations. And density is also affected by the anion type. Furthermore, the volume of ions, NBO charges, and the interactions of anions and cations were calculated by Gaussian03 to explain the obtained density results. The second-order polynomial equation was adopted to correlate the relationship of density and temperature. Then, an isobaric thermal expansion coefficient, molecular volume, and lattice potential energy were obtained from the density data. Viscosity was determined from 323.15 K to 368.15 K, p = 0.101 MPa. It is determined that the viscosity of ILs decreases with an increase in the temperature but increases with an increase in the alkyl chain length of cations. The temperature dependence of viscosity was described by the Vogel-Fulcher-Tamman (VFT) model, and the activation energy of viscous flow (Eη) was obtained. Furthermore, the decomposition temperature (Td), glass transition temperature (Tg), and melting temperature (Tm) of ILs were obtained from the results of TGA and DSC.

Synthesis of Cross-Linked Poly Acidic Ionic Liquids and its Application in Biodiesel Production

Brӧnsted acidic poly ionic liquid (PIL-M) was successfully prepared by free-radical polymerization. The surface area of the heterogeneous catalyst was 301.1 m2/g. The result of thermogravimetric (TG) proved that PIL-M had good thermal stability (decompose at 410 °C). The optimal reaction condition was as follows: 6 wt% catalyst amount, reaction temperature 80 °C, the ratio of methanol to oleic acid 9:1 and reaction time 3 h. Under the optimal condition, the yield of methyl oleate was up to 95.9%. The excellent catalytic activity of PIL-M in the product of biodiesel benefit from its excellent properties such as high surface area (301.1 m2/g) and hierarchical nanopores. Compared with commercial resin (Amberlyst 15) and other catalysts, PIL-M showed better catalytic activity. The yield of methyl oleate was still over 90% after four times reuse. The structure of PIL-M kept stable after four times reuse, which was confirmed by the FT-IR spectrum.

Synthesis, thermophysical properties and CO2 sorption of imidazolium, thiazolium, iminium and morpholinium-based protic ionic liquids paired with 2-acrylamido-2-methyl-1-propanesulfonate anion

The present study aims to investigate the temperature dependence of the physicochemical properties of four cations (namely 2-chloro-1,3-dimethylimidazolium [diMeim], 3-benzyl-5-(2-hydroxyethyl)-4-thiazolium [bnthia], (chloromethylene)dimethyl iminium [diMeimi] and morpholinium [mrph]) paired with common 2-acrylamido-2methyl-1-propanesulfonate [AMPS] anion. The density and viscosity of the resulting ionic liquids (ILs) were measured within temperature range of (293.15–363.15) K while refractive indexes were determined within temperature range of (288.15–333.15) K. Among the investigated novel ILs, [bnthia][AMPS] showed the highest viscosity and density over the entire temperature range and an enhanced CO2 dissolution of 0.65 mol fraction was observed at 1 MPa and 298.15 K. Furthermore, the Henry's constant of [bnthia][AMPS] was found to be 1.199 MPa which was 23.7, 32.6, and 56.0% less than [diMeim][AMPS], [diMeimi][AMPS] and [mrph][AMPS], respectively. The present study provides a detailed insight to understand structure-activity relation between physicochemical properties and CO2 solubility of studied ILs.

Photocatalytic degradation of phenol using ionic liquid stabilized TiO2 nanoparticles

This paper describes the successful synthesis of ionic liquid stabilized TiO2 and it was characterized by various instrumental techniques such as UV–vis, FT-IR, XRD and TEM analysis. The photocatalytic activity of ionic liquid stabilized TiO2 nanoparticles (TiO2 NPs) was evaluated by analyzing the degradation of aqueous phenol solution by UV irradiation. The effect of phase composition of TiO2 NPs namely, anatase and rutile, on photocatalytic activity was studied using chemical oxygen demand (COD) and fluorescence measurements. The results show that pure anatase phase shows lesser photocatalytic activity compared to a mixed anatase: rutile phase (80:20) and the degradation mechanism is also investigated. The remarkable point is that the ionic liquid tunes the phases of the TiO2 NPs and this work provides a promising approach to fabricate TiO2 based catalyst with efficient photocatalytic performance.

Synthesis of bi-functionalized ionic liquid — mesoporous alumina composite material and its CO2 capture capacity

Bi-functionalized ionic liquid (IL) — mesoporous alumina (MA) composite material was synthesized and used for CO2 capture. Ordered mesoporous alumina was synthesized by self-assembly method with aluminum isopropoxide as aluminum source. Then bi-functionalized ionic liquid 1-methoxyethyl-3-methyl imidazole glycinate ([MOEmim][Gly]) was immobilized on mesoporous alumina by ultrasonic-assisted impregnation method. Ordered mesostructure of alumina keeps well in the composite material. Compared with bi-functionalized ionic liquid, thermal stability of the composite material greatly improved. Finally, CO2 capture capacity of IL-MA composite material was studied under different temperatures. On the basis of both capture capacity and capture rate, 40 ·C is the optimal temperature. The capture capacity is 1.42 mol·mol IL−1 — equivalent to 144 mg·g sorben−1, which is higher than IL or MA alone. Furthermore, the capture capacity of composite material almost maintains constant after eight capture-regeneration cycles.

Synthesis of new water-soluble ionic liquids and their antibacterial profile against gram-positive and gram-negative bacteria

A series of imidazolium bromide salts (NIM-Br 1a, 1b and 1c) bearing different lengths of alkyl chains were synthesized and theirin vitro antibacterial activities were determined by measuring the minimum inhibitory concentration (MIC) values for Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa and Enterococcus faecalis. In addition, these imidazolium derivatives were also evaluated against biofilm produced by these bacterial strains. All compounds were found to be effective against Gram-positive and Gram-negative bacteria, and also more effective on the S. aureus biofilm production than the others.

Synthesis, characterization and supercapacitor application of ionic liquid incorporated nanocomposites based on SPSU/Silicon dioxide

In this study, we report about novel polymer electrolytes containing sulfonated polysulfone (SPSU) as the polymer matrix, silicon dioxide (SiO2) as nano additive and ionic liquid (1-Ethyl-3-methyl-imidazolium tetrafluoroborate) IL) as a softening agent. In addition, the physical and chemical properties of ionic liquid containing nanocomposite gel polymer electrolytes were studied and subsequently the optimized electrolyte was used to assemble the supercapacitor device. Nanocomposite gel polymer electrolytes demonstrated higher thermal stability and lower glass transition temperatures (Tg) required for supercapacitor application. The ion conductivity of the nanocomposite polymer electrolytes was investigated using a dielectric-impedance analyzer at various temperatures. The highest conductivities were obtained for the samples SPSU/0.1IL and SPSU/%3n SiO2/0.2IL with values 3.1 × 10−4 and 3.2 × 10−3 S cm−1 at 100 °C, respectively. In addition, symmetrical cell formation based on Al/C/SPSU/%3nSiO2/0.2IL/C/Al showed a maximum specific capacitance of 134.1 F g−1 at 1 A g−1. The same cell also yielded a maximum energy density in supercapacitor as 18.6 Wh kg−1 at a power density of 1089 W kg−1.

Ionic liquid mediated morphologically improved lanthanum oxide nanoparticles by Andrographis paniculata leaves extract and its biomedical applications

Greener synthesis of ionic liquid (IL) assisted lanthanum oxide (La2O3) nanoparticles (NPs) was followed using Andrographis paniculata leaves extract by hydrothermal method at low temperature. The IL assisted La2O3 (La2O3-IL) NPs were characterized by various properties such as structural, spectral, optical, morphological, and biological studies. Powder X-ray diffraction studies confirm that La2O3-IL NPs crystallize in the form of body-centered cubic structure and average crystalline size is shown ∼43 nm. FTIR and Laser Raman spectroscopy confirm the La–O, O–H and various functional groups. The La–O stretching vibration band attributes at 639 cm−1. The optical property of La2O3-IL NPs was characterized by UV-Vis and photoluminescence spectroscopy. The sharp and intense absorbance peak observed in the UV region at 288 nm can be assigned. In the PL spectrum, we observe two different emission bands like blue and green emission. The morphological and particle size determination were investigated by SEM with EDX spectra and TEM analyses. The agglomerated particles of hexagonal, spherical, and parallelogram shape are observed in the TEM images. The chemical elements, binding energies as well as La metal states on the surface of these synthesized NPs were determined using XPS. La2O3 NPs for good biological activities regarding antibacterial and anti-inflammatory potentials could be utilized in different biological applications to the food and biomedical industries. La2O3-IL has a high percentage of inhibitions than La2O3 and standard diclofenac.

Synthesis, physicochemical characteristics and antimicrobial studies of ethyl-substituted imidazolium-based surface active ionic liquids (SAILs)

A series containing higher members of ethyl-substituted imidazolium-based surface active ionic liquids (SAILs) [Cneim]Br, (n = 12, 14, 16) has been synthesized by a two-step reaction pathway. They were characterized by FT-IR, 1H NMR and 13C NMR and their effect on self-aggregation behavior in aqueous solution has been examined, employing conductometric and tensiometric methods besides fluorescence measurements and UV-visible spectroscopy. The conductivity data were recorded at different temperatures and thermodynamic parameters of micelle formation such as, standard Gibbs free energy (∆Gmo), standard enthalpy (∆Hmo), standard entropy (∆Smo) were evaluated. The process of micellization is entropy driven and supported by Gibbs free energy measurements. Interfacial parameters have also been evaluated by employing surface tension technique. The SAILs were also analyzed for their antimicrobial activity by taking eleven kinds of bacterial strains.

Low‐Temperature Synthesis of Oxides in Ionic Liquids: Ozone‐Mediated Formation of Co3O4 Nanoparticles Monitored by In Situ Infrared Spectroscopy

AbstractFor most functional oxides, structure‐selective synthesis is the key for the task‐specific production of nanomaterials. Herein, the low‐temperature synthesis in ionic liquids (ILs) is an attractive strategy to produce nanomaterials which are not accessible otherwise is described. In this study, a bench‐scale synthesis route toward Co3O4 by applying O3 on the molecular precursor Co2(CO)8 in IL medium is reported. The Co3O4 nanoparticles (NPs) are characterized by infrared (IR) spectroscopy, X‐ray diffraction (XRD), and transmission electron microscopy (TEM). This protocol yields Co3O4 with good crystallinity and narrow size distribution. In addition to conventional materials characterization, a new experimental approach is described in which the material synthesis in situ by IR reflection absorption spectroscopy (IRAS) (in situ IRAS) is followed. The in situ approach provides additional information on the growth mechanisms and kinetics and confirms that O3 treatment of Co2(CO)8 in IL exclusively yields pure Co3O4 without the formation of byproducts or intermediates.

4‐Amino‐1‐Butyl‐1,2,4‐Triazolium Nitrate – Synthesis and Characterization

AbstractAn improved synthesis of the energetic ionic liquid 4‐amino‐1‐butyl‐1,2,4‐triazolium nitrate (C4 N) is presented via a one‐step metal‐free route using butyl nitrate. C4 N offers promising properties like very low vapour pressure combined with good insensitivity. In addition, long‐term and thermal stability were investigated. The potential use as an energetic additive to improve the rheological properties of GAP‐based energetic polymers was studied resulting in an almost four times lower viscosity at 15 wt.‐% C4 N content. As an additive to a nitromethane‐based monopropellant C4 N works as burning rate modifier which additionally reduces the propellant sensitivity.

Synthesis and investigation of halogen-free phosphonium-based ionic liquids for lubrication applications

In the present work, three kinds of halogen-free ionic liquids (ILs) incorporating long-chain quaternary phosphonium as cations and dioctylsulfosuccinate (DOSS) as the anion were synthesized and characterized and the tribological properties of phosphonium ionic liquids were investigated as neat lubricants for steel ball–steel disc friction pairs at room temperature (RT) and elevated temperature (100 °C). The ILs were found to be noncorrosive and highly thermally stable and showed better antiwear and friction reduction performance than commercially available synthetic lube base oil poly-α-olefin (PAO10) and conventionally used IL 1-methyl-3-hexylimidazolium hexafluorophosphate (L-P106). Scanning electron microscopy (SEM) and energy-dispersive spectroscopic (EDS) analysis of the worn-out surfaces of the steel discs was performed and the results revealed that physical adsorption and tribochemical reactions occurred and formed a protective boundary film on the worn steel surface to prevent direct steel–steel contact between rubbing surfaces.

Synthesis of ionic liquids with multifunctional tribological properties as excellent single‐component package additives for turbine oils

AbstractThree benzotriazole‐bearing imidoazolium‐based ionic liquids (ILs) have been synthesized. The ILs were identified by 1HNMR and Fourier‐transform infrared (FTIR) techniques. The thermogravimetric analysis showed that they are highly nonvolatile and have extremely high flash points. The synthesized ILs were used in turbine oil formulation, and their lubrication properties were critically examined and compared to commercially available package additives. The tribological tests proved that the ILs act as an effective antifriction, antiwear (AW), and extreme pressure (EP) additives. Performance studies indicated that the synthesized ILs impart excellent antioxidation and corrosion protection to the lubricant with minimum acidity change. The elemental analysis proved absence of toxic and dangerous elements in the lubricant, a confirmation that the ILs are potential environmentally friendly lubricants. The results also confirmed that the synthesized ILs are ideal single‐component package additives in the lubricant industry, i.e., one molecule imparts several favorable functionalities to the lubricant..

Toward Designing “Sweet” Ionic Liquids Containing a Natural Terpene Moiety as Effective Wood Preservatives

This study is focused on the utilization of naturally occurring terpene alcohol in the synthesis of ionic liquids (ILs) and their application potential in wood protection. A new series of ILs containing a natural, renewable source of (−)-menthol in the cation and a saccharinate derivative as the anion were obtained with a high yield under mild process conditions. The potential applications of synthesized compounds that belong to surface-active compounds were assessed for wood preservation, and they showed positive results. Laboratory tests of their activity against fungi and saccharinate-based chiral ionic liquid (CIL) bonding with Scots pine (Pinus sylvestris L.) wood are described. The biological results for salts with alkyl substituents ranging from pentyl to octyl chains are very promising, and their activity is similar to, and even higher than, that of the commonly used material benzalkonium chloride. The fungicidal values of saccharinate-based CILs against Coniophora puteana ranged from 2.75 to 4.4 ...

Synthesis of ionic liquids as novel emulsifier and demulsifiers

This work presents synthesis of several imidazolium based ionic liquids (ILs) as emulsifiers and demulsifiers in the lubricants and petroleum industry. The first synthesized IL was 2,2-dimethylhydroxyl 1,3-bis (3-dodecyl imidazolium bromide) propane which didn't show any emulsifying/demulsifying property. The second IL, which also did not have any emulsifying/demulsifying property, was synthesized by anion exchange of first IL with hexafluorophosphate. The etherification of polar hydroxyl groups of first IL with long chain dodecylbromide gave third IL and subsequent anion exchange by hexafluorophosphate gave fourth IL, which both provided highly stable water-in-oil emulsions. Besides, they also act as metal passivation and anti-rusting agents. The substitution of first IL onto Fe3O4 nanoparticle surfaces and its addition to crude oil emulsions caused imminent emulsion collapse. A solubility index was defined to classify the miscibility of the ILs in a broad range of oil mediums. Complementary emulsion studies at microscopic level, i.e., analysis of size distribution and growth rate of droplets approved the effectiveness of the synthesized emulsifier and demulsifiers. These observations led us to the conclusion that by modification of structure of ILs, they show completely different physicochemical properties. In summary, they can be regarded as excellent candidates for replacement of their commercial counterparts.

Evaluation of ionic liquid “greenness”-cytotoxicity of ionic liquids

Ionic liquids have become a hot spot in research and application due to their own superiority. At the same time, the “risk” of ionic liquids has attracted more and more attention. The toxicity of ionic liquids varies according to the target. We have to obtain the toxicity data of ionic liquids on various organisms and cell lines, fill in the blanks of ionic liquid toxicity data and clarify the toxicity mechanism. Only in this way, can we lay the foundation for the design and synthesis of new ionic liquids that are truly non-toxic, environmentally friendly and meet functional requirements. In this experiment, 1-ethyl-3-imidazole diethyl phosphate ([Emim]DEP) was prepared by using 1-methylimidazole and triethyl phosphate as raw materials. The rat cranial anterior osteoblast cell line (MC3T3-E1) was used as the research object, using MTT method, fluorescent death-sense staining observation and flow cytometry to study the cytotoxicity of 1-allyl-3-methylimidazolium chloride ([Emim]DEP) type ionic liquid. This article aims to determine the median lethal concentration by the inhibition rate-concentration curve of [Emim]DEP type ionic liquid and measure cell survival index at this concentration.

Synthesis of symmetric ionic liquids and their evaluation of nonlinear optical properties

The synthesis, functionalization and anion-exchange of symmetric ionic liquids (SILs) and their nonlinear optical studies are reported. Imidazolium cation was obtained in 75–99% of yield by condensation reaction (Debus-Radziszewski) using different amine derivatives and employing inorganic and organic acid as catalyst. The nonlinear optical properties were evaluated by Z scan technique, at 514 nm of Ar laser, where the symmetric ionic liquid showed a nonlinear optical effect. The values of n2 are of the order ~10−8 cm2/W, while β value is 10−5 cm/W. The nonlinear refractive index increases due to the high concentration, symmetric structures and non-aliphatic chains. On the other hand, the coefficient of nonlinear absorption increases at low concentrations with symmetric structures and aliphatic chains.

Design of Nonsteroidal Anti-Inflammatory Drug-Based Ionic Liquids with Improved Water Solubility and Drug Delivery

We here report the synthesis of ionic liquids (ILs) composed of the cholinium cation and anions derived from nonsteroidal anti-inflammatory drugs (NSAIDs), namely ibuprofen, ketoprofen, and (S)-naproxen, and their incorporation into bacterial nanocellulose envisaging their use in topical drug delivery systems. The chemical structure of the synthesized ILs was confirmed by spectroscopic techniques, and thermal analysis confirming their categorization as ionic liquids with melting temperatures below 100 °C and resistance to autoclaving. The synthesized ILs display an aqueous solubility (at pH 7.4) ranging between 120 and 360 mM, which is up to 100 times higher than the solubility of the respective NSAID precursors, thus contributing to improved bioavailability. Their incorporation into bacterial cellulose originated transparent and homogeneous membranes. Thermogravimetric analysis (stable up to at least 225 °C) and mechanical assays (with minimum Young’s modulus of 937 MPa, maximum stress of 33 MPa and elon...