Nowadays the knowledge of thermodynamic properties for amino acid ionic liquids (AAILs) has been paramount for the design of many chemical processes. In this present work, a series of cholinium-based AAILs ([Ch][AA]) were synthesized by neutralization of choline hydroxide solution with five amino acids and then were characterized by 1 H NMR, Fourier transform infrared (FT-IR), elemental analysis, thermogravimetry, and differential scanning calorimetry (DSC) analysis. Physico-chemical properties such as density, viscosity, refractive index, and conductivity were measured and correlated with the empirical equations in a wide temperature range. The thermal expansion coefficient values were also calculated from the acquired experimental density values. From the experimental data, it was found that the density, viscosity, and refractive index decreased while conductivity increased with the increase of temperature. The correlation results were proposed to be in good agreement with the experimental data, and optimal fitting parameters were presented. In addition, the coefficient of thermal expansion was considered to be independent of temperature in the range of (298.15 to 353.15) K.
A family of thermally regulated molybdate-based ionic liquids has been developed for highly efficient synthesis of various flavones, imines, and benzyl benzoates through one-pot oxidative cascade catalysis.
It is remarkable that Brønsted acidic ionic liquids (BAILs) have several unique advantages in the acid-catalysis reaction, which avoids the technical issues raised from mineral acids. The kinetics for the ketalization of cyclohexanone with glycol using BAILs as catalysts was therefore studied for the first time. The effects of various parameters such as kind of BAILs, temperature, catalyst loading, and molar ratio of the reactants on the conversion of cyclohexanone were examined in detail, and a pseudohomogeneous (PH) kinetic model was used successfully to correlate the experimental data in the temperature range from 313.15 to 343.15 K. The kinetic parameters such as reaction rate constant, activation energy, and chemical equilibrium constant then were proposed and utilized to interpret the catalytic activities of the BAILs catalysts. It was also validated from the comparison of catalytic performance among the BAILs, H 2 SO 4 , and solid resin that the BAILs were considered to be environmentally friendly and high efficient catalysts, and were suggested to replace mineral and solid acids in the synthesis of ketal.
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