Equilibrium solubility, density, viscosity and corrosion rate of carbon dioxide in potassium lysinate solution

•Solubility of CO2 in aqueous solutions of potassium lysinate was measured.•Potassium lysinate has a higher CO2 loading capacity compared to MEA.•CO2 solubility decreases with an increase in potassium lysinate concentration and temperature.•Viscosity and corrosion rate increase when the molar concentration of potassium lysinate increases.

Aqueous solution of potassium lysinate has been characterized through CO2 solubility, density, viscosity and corrosion rate measurements in order to investigate the possible use of this amino acid for CO2 absorption. The equilibrium solubility of CO2 in 0.5, 1.5 and 2.5 mol dm−3 (M) potassium lysinate solutions were measured experimentally with a stirred batch reactor at the CO2 partial pressure ranging from 0 to 45 kPa (low partial pressures) and temperatures between 298 and 313 K. The results of the gas solubility are presented as loading capacity (mole CO2/mole potassium lysinate) as function of CO2 partial pressure. Obtained data showed that loading capacity decreases with increase in concentration of potassium lysinate and temperature. The densities and viscosities of solutions were determined at the same conditions of the solubility measurement. Corrosion rate tests were also measured on carbon steel for the same solution concentrations but at 308 K. It was observed that viscosity and corrosion rate increase when the molar concentration of potassium lysinate increases.