Studies on the Effect of Amino Acids on Self‐aggregation Behavior and Volumetric Studies of Surface‐Active Ionic Liquid at Different Temperatures

Abstract The aqueous solutions of IL 1‐dodecyl‐3‐methylimidazolium iodide ([C 12 mim][I]) in the absence and the presence of amino acids (AAs) DL‐Valine and DL‐Serine across varying temperatures at atmospheric pressure, as an external additive have been examined by density, electrical conductivity, UV–visible, and DLS measurements. Experimentally measured densities facilitated the calculation of thermodynamic parameters, including the apparent molar volumes, ϕ v , partial molar volumes, , transfer volumes, (tr), and partial molar expansibilities, , across a temperature range of 288.15–308.15 K. The critical micelle concentration (CMC) of IL has been investigated in the absence and presence of amino acid to acquire a better understanding of the colloidal behavior of IL in presence of amino acid as an external additive. The thermodynamic parameters of micellization like Gibbs energy change (), the standard enthalpy change (), and the standard entropy change (), have been scrutinized from the dependence of CMC on temperatures. It is also calculated molar conductivities and limiting molar conductivities () based on specific conductivity ( κ ), providing insights into the interactions within these systems. Additionally, UV–visible absorption spectroscopy, conducted at 298.15 K with fluorescein as a probe, was employed to further examine the interactions present within the studied solutions.