Temperature-dependent physicochemical studies of sodium salicylate in aqueous solutions of ionic liquids {[BMIm]Br and [EMIm]Cl}

The current study explores the impact of two different imidazolium based ionic liquids, having diverse side chains and anions: 1-ethyl-3-methylimidazolium chloride ([EMIm]Cl) and 1‑butyl‑3-methylimidazolium bromide ([BMIm]Br) on the thermodynamic and transport properties of sodium salicylate. This inquiry examines the sodium salicylate's density, sound velocity, and viscosity within aqueous solutions of these ionic liquids across a temperature range of 283.15 K to 313.15 K at atmospheric pressure. Various parameters, including apparent molar volume ($V_{\varphi }$), limiting apparent molar volume (${V^o}_{\varphi }$), transfer volume (${\Delta }_{tr}V{{}^{\circ }}_{\varphi }$), limiting apparent molar expansibility ($E{{}^{\circ }}_{\varnothing }),$ Hepler's constant, apparent molar isentropic compression ($K_{\varphi ,s}$), limiting apparent molar isentropic compression ($K{{}^{\circ }}_{\varphi ,s}$), transfer parameter of isentropic compression (${\Delta }_{tr}K{{}^{\circ }}_{\varphi ,S}$), and viscosity B-coefficient, were computed from experimental values. Additionally, we have analyzed the trends in computed parameters, considering the interactions between `solute and solvent along with solute-solute interactions in the systems under investigation. Our results suggest a predominance of hydrophilic-hydrophilic and ion-hydrophilic interactions within studied systems. The observed magnitudes of these parameters affirm a stronger interaction between sodium salicylate and [BMIm]Br in comparison to those with [EMIm]Cl.