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The experimental solubility data of l-glutamic acid in pure water, formic acid, methanol, 1-propanol, 2-propanol, acetonitrile, and binary mixtures (formic acid + water, methanol + water, 2-propanol + water, acetonitrile + water) with different compositions were carried out at temperatures ranging from (283.15 to 328.15) K by the static analytic method. The solubility measurements showed that formic acid and its aqueous mixtures recorded a higher solubility than methanol + water, 2-propanol + water, and acetonitrile + water for the same composition at each temperature. Moreover, except formic acid the addition of methanol, 2-propanol, and acetonitrile to its aqueous mixtures resulted in the decrease in solubility of l-glutamic acid. The experimental data was fitted using different thermodynamic models such as the Buchowski-Ksiazczak equation, the Van't Hoff equation, the modified Apelblat equation, and the NRTL model, and the optimum values of the regressed parameters were obtained. The modified Apelblat equation, Buchowski-Ksiazczak equation, and NRTL activity coefficient model were fitted to the pure solvents solubility data, while the modified Apelblat, modified Apelblat-Jouyban-Acree, and NRTL models were used for the binary solvent systems. The results demonstrated formic acid as a cosolvent in the dissolution of l-glutamic acid in formic acid + water binary mixtures, while others exhibited an antisolvent effect on the solubilization of l-glutamic acid in their respective aqueous mixtures.

This paper describes an alternative process for chloroform decomposition via nonthermal plasma polymerization at atmospheric pressure and investigates the effect of methane and hydrogen addition on the process. The effect of both additives was assessed separately, where experiments were conducted in a double dielectric barrier discharge reactor under nonoxidative conditions. The most profound impact of the additives was a significant increase in the yield of non-cross-linked polymer produced compared to that in their absence. The addition of methane resulted in a 120% increase in polymer yield, while in hydrogen the increase was 31%. Critical parameters such as effect of the methane and hydrogen concentration on the conversion of chloroform at various applied voltages, the product distribution, mass balance, and polymer characterization are elucidated in this paper. Single pass conversions of 61% and 68% (with corresponding mass balances of 98% and 95%, respectively) were achieved for CHCl3 + CH4 and CHCl3 + H2 feed scenarios, respectively. Furthermore, a polymerization mechanism which explains the formation of major chain structures as well as structural defects in the polymer is expounded upon in the paper.

The reaction of CCl3F (CFC-11) with CH4 (in an argon bath gas) in a dielectric barrier discharge nonequilibrium plasma was examined. Oxygen and nitrogen were excluded from the feed stream and the reactions resulted in the production of fluorine-containing polymers, as well as a range of gaseous products including H2, HCl, HF, C2H3F, C2H3Cl, C2H2ClF, CHCl2F, CCl2F2, CH3Cl, CH2Cl2, CHCl3, and C2Cl4. The polymeric material synthesized during reaction is characterized as being non-cross-linked and random in nature, containing functional groups including CH3, CH2, CHCl, CHF, CF2, and CF3. The conversion level of CCl3F increased from 37% to 63% as the input energy density increased from 3 to 13 kJ L–1 (the applied voltage range was 14.1 to 15.2 kV, peak–peak). The electrical discharge was characterized and found to be a slight modification of filamentary discharge toward a diffuse discharge due to the presence of the relatively low concentration of CCl3F and CH4 (less than 2% each) in argon. A reaction mechanis...

Two Australian thermal coals were treated with four different ionic liquids (ILs) at temperatures as low as 100 °C. The ILs used were 1-butylpyridinium chloride ([Bpyd][Cl]), 1-ethyl-3-methylimidazolium dicyanamide ([Emim][DCM]), 1-butyl-3-methylimidazolium chloride ([Bmim][Cl]), and 1-butyl-3-methylimidazolium tricyanomethanide ([Bmim][TCM]). Visual comparisons were made between the raw and IL-treated coals via optical microscopy. Changes in thermal behavior of these treated coals were compared against raw coals via pyrolysis experiments in a thermogravimetric analyzer (TGA). Changes in functional group composition in the treated coals were probed via Fourier transform infrared (FTIR) spectroscopy. The recovered ILs were also analyzed via FTIR and nuclear magnetic resonance (NMR) spectroscopies to observe any changes after recovery. Low-temperature IL treatment of each of the coals resulted in fragmentation and fracturing, reducing the average particle size. An increase in mass loss in the treated coals ...

A dielectric barrier discharge (DBD) nonthermal plasma was used to convert a range of fluorocarbons into useful polymeric products. Reactions were conducted at atmospheric pressure, in an argon bath gas and where methane was added as reactant. The bulk gas temperature was less than 150 °C and yielded polymers from a number of methane/fluorocarbon mixtures, including fluorocarbons such as halons, chlorofluorocarbons (CFCs), hydrochlorofluorocarbons (HCFCs), hydrofluorocarbons (HFCs), and perfluorocarbons (PFCs). The results of gel permeation chromatography (GPC) reveal that a potentially valuable polymer is synthesized, with a number average molecular weight of between 60 000 and 130 000 g mol -1 and a polydispersity index (PDI) of between 1.2 and 2.9, depending on the fluorochemical converted.