Solvate Ionic Liquids: Assessing the Possibility of Determining the Composition by Means of Gas–Liquid Chromatography

Abstract

A study is performed of the possibility of using gas–liquid chromatography (GLC) to determine the composition of solutions of lithium salts in aprotic dipolar solvents and solvate ionic liquids. The objects of study are solutions of lithium perchlorate and lithium trifluoromethanesulfonate in sulfolane and solvate complexes of lithium perchlorate with sulfolane obtained in two ways: direct interaction of the initial components in a given molar ratio and interaction of the components in a common solvent with its subsequent removal via evaporation. It is shown that GLC is a convenient way of determining the content of a solvating solvent in the composition of solutions and solvate ionic liquids. The presence of lithium salt in the analyzed solutions does not affect the period of retention; instead, it raises the degree of asymmetry of the chromatographic peak of the solvent and manifestation of the tailing effect. It is found that the presence of salt in the considered system also does not reduce the accuracy of determining the solvent content. The error in determining the content of solvent in solutions of lithium salts and solvate complexes by GLC is no greater than 1%.