Volumetric Properties of Aqueous Sodium Salt of Amino Acids as CO2 Capture Solvent

Abstract

Objectives: To produce new and accurate data of density of aqueous solution of amino acid salts at different temperatures and to correlate it with molality. Methods: The densities of aqueous solutions of sodium salts of Amino acids such as L-cysteine, L-leucine, L-proline and L-valine have been measured using double-arm Pycnometer, placed in a transparent glass-walled water bath having thermal stability of (0.01 K) at concentrations range (0.01 to 0.15) mol L-1 and at 298.15, 303.15, 308.15, and 313.15 K. From density data ahead, apparent molar volumes (Vϕ ), the partial molar volumes (Vϕ 0), expansion coefficient (E¥) and Hepler’s constant ( ¶ 2Vϕ 0=¶ T2) were calculated and analysed on the basis of the intermolecular interaction and molecular structure. Findings: The densities are observed to increase with concentration and decrease with increasing temperature. The positive values of partial molar volume (Vϕ 0) indicate strong sodium amino acids -water interactions. Novelty: For studied aqueous sodium salt solution of Amino acids, such properties have not yet been reported in the open literature and at such a lower concentrations range (0.01 to 0.15) mol L-1. Keywords: Density; Sodium Salt Amino Acid; Apparent Molar Volume; Helper’s Constant