Papers by Keyword: Ionic Liquid (IL)

Abstract: In this paper, the effect of C₃H₆N₆modified by imidazolium based Ionic Liquid 1-butyl-methylimidazolium hexafluorophosphate ([BMIM]PF₆) on polyurethane rigid foam flame retardant properties was conducted.The results show that the flame retardant properties of C₃H₆N₆ modified with Ionic Liquid significantly increased and the LOI increased form 22.3 to 24.5. In the modification process, the ionic liquid mass have a very noticeable effect to the flame retardant property and when [BMIM]PF₆ and C₃H₆N₆ in quality was 4:6, Fire-retardant effect was best.Compared with the prior to the modification, C₃H₆N₆ modified can increase effective Flame resistance of materials, horizontal burning speed from 67.6mm/min down to 33.4mm/min.Thermal degradation data show that C₃H₆N₆ modified could improve initial decomposition temperature and reminder yield of rigid polyurethane foam,and then heat release reduced, the decomposition controlled,thermal stability increased.

Abstract: Recently, room temperature ionic liquids (RTILs) have been widely used in dissolution, homogeneous modification of cellulose. Cellulose only could be dissolved in RTILs at elevated temperature. Herein, effect of dissolution condition on microcrystalline cellulose in 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) ionic liquid was studied. The results indicated that the degree of polymerization (DP) of regenerated cellulose decreased from 161 to 83 with the increasing of dissolution temperature in the range of 70 °C to 110 °C, whereas the DP was affected by dissolution time slightly. Moreover, after dissolution [Bmim]Cl could be recycled by distillation and vacuum drying. The recycled [Bmim]Cl also had good dissolving capability of cellulose, and its FTIR spectra was similar to that of original [Bmim]Cl.

Abstract: Liquid crystal was formed in a ternary system of tetraethylene glycol lauryl ether, water and 1-ethyl-3-methylimidazolium hexafluorophosphate. Its structure was identified by polarized optical microscopy and small-angle X-ray scattering techniques. Compared to that in the binary system, lamellar phase was retained with the addition of a small amount of imidazolium salt. Molecules of 1-ethyl-3-methylimidazolium hexafluorophosphate were considered to be solubilized in the polar domain of the ordered assemblies. Results on their influence on the lamellar phase enlighten the use of imidazolium salts to modulate liquid crystalline materials and other assemblies.

Abstract: Cerium Oxide (CeO₂) nanocubes are synthesized by using hydrothermal treatment method in the presence of four different types of ionic liquid such as acetate anion, phosphate anion, and dicyanamide anion. Ceria nanocubes has been consisted with average size of 16 to 31 nm in diameter and characterized by transmission electron microscope (TEM), X-ray diffraction (XRD), and surface analyzer and porosimetry analysis (ASAP). Ceria nanocubes have higher photocatalytical ability in the degradation of methylene blue as compared to commercial ceria nanoparticles which are confirmed through ultraviolet-visible spectroscopy (UV/Vis).

Abstract: The frequent usage of cationic dyes is in the textile and leather industries. However, they are not only utilized during the dying process, but also they are recovered at the end of the process. Hence, the removal of dye from huge quantity of wastewater is necessary. In this paper methylene blue as a cationic dye have been extracted successfully into an ionic liquid namely 1-hexyl-3-methyl-imidazolium bis (trifluoromethylsulfonyl) imide, abbreviated as [HMIM][TF2N]. To investigate the feasibility of using (IL) to dye removal from aqueous solutions batch experiments were performed under different process conditions like initial dye concentration, pH and temperature. Also adsorption data were analyzed using isotherms models and was found to conform to the principle of Lagmuir model with good correlation coefficients (R² = 0.9896).

Abstract: Titania nanomaterial flower structure is synthesized through the ionothermal route and is used for the degradation of sulfan blue (SB) through the photo catalysis process. The ionic liquid used is 1-butyl-3-methypyridium dicyanamide ([Bmpm]DCN). The particle sizes and surface morphologies are characterized by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and Brunauer–Emmett–Teller (BET). Three types of titania have been compared for their degradation performance, namely commercial titania (TP), titania nanotube (TN), and titania flower (TF). The size of the particle is found to be approximately 33 nm from the FE–SEM analysis. The BET measures the highest surface area of 220 m² g^-1 and pore volume of 0.15 cm³ g^-1 for the TF. The degradation of binary dye is more favorable in alkaline solution with pH 14 while varying the dosage of the commercial TiO₂ from 0.025–0.2 g reveals an increase in the rate of degradation with optimum dosage is found to be 0.2 g. Results show that TF degradation rate is higher as compared to TP and TN.

Abstract: Nowadays, ionic liquids have been widely used in desulfurization process. However, the synthesis costs, performance efficiencies and problems related to waste waters contaminated with ionic liquids are the major issues that need to be considered. Thus, recovery method is one of the alternatives to overcome the current issues. 1-butyl-3-methylimidazolium-based ionic liquids with three different anions: dicyanamide (N(CN)₂), thiocyanate (SCN) and methylsulfate (CH₃SO₄) were chosen for the study because they are the common ionic liquids used in desulfurization. The recovery process used is water washing which is the cheapest and easiest recovery method. Even though the contaminants in the spent ionic liquids can easily be removed, we found that the recovered ionic liquids contained higher percentage of water as compared to the pure and spent ionic liquids. Thus, the aim of this current work is to study on the feasibility of the spent ionic liquids to be recovered and their performance on desulfurization after being recovered.

Abstract: Selection of potential ionic liquid (IL) is carried out in this work using COSMO-RS by analyzing the interaction between dibenzothiophene (DBT) and IL in dodecane. Sigma profile, capacity and selectivity at infinite dilution were used to predict the suitable ILs in desulfurization. Result shows that increasing alkyl length and incorporating nitrile group will increase the capacity and selectivity respectively. 1-butyl-6-methylquinolonium [C₄mquin]⁺, 1-butyl-3-methylimidazolium [Bmim]⁺, thiocyanate [SCN]^- and dicyanamide [N(CN)₂]^- are potentially good cations and anions.

Abstract: Active pharmaceutical ingredients-ionic liquids (APIs-ILs) in which, when compared to active pharmaceutical ingredients hydrochloride (APIs-HCl), exhibits better solubility, increased thermal stability and significant enhancement in the efficiency of APIs. Three novel flufenamic-ILs were synthesized and their density and viscosities were determined and reported as a function of temperature. From the experimental density data the crystal energy, molecular volume and standard entropy was estimated. The result showed that the density and viscosities decrease with increasing temperature in these four ionic liquids.

Abstract: In this study, the performance of 1-(2-Hydroxyethyle) 3-methylimidazolium chloride [OH-EMIM][Cl] and 1-(2-Hydroxyethyle) 3-methylimidazolium bromide [OH-EMIM][Br] was investigated as thermodynamic gas hydrate inhibitors. The dissociation temperature was determined for methane gas hydrates using a high pressure micro deferential scanning calorimeter at a pressure range of 36-97 bar. Both ionic liquids (ILs) were studied at concentrations of 5, 10, 15, 20 and 25 wt% then their performance was compared with commercially available inhibitors. It was observed that both ILs shift the methane hydrate equilibrium curve to lower temperature and higher pressure; and the performance of [OH-EMIM][Cl] is better than [OH-EMIM][Br]. Nevertheless both of them were found to be less effective compared to methanol and mono ethylene glycol.