Solubilities of carbon dioxide and densities of aqueous sodium glycinate solutions before and after CO absorption

The densities of aqueous solutions of sodium glycinate (SG) were measured for a range of concentrations [(1, 5, 10, 15, 20, and 30) % wt] and at a temperature range (298.15 to 353.15) K. The solubility of CO₂ in aqueous solution of sodium glycinate was measured for the same concentration range and at two temperatures (298.15 and 313.15) K, over CO₂ partial pressure ranging from (100 to 2500) kPa. The densities of aqueous solutions of sodium glycinate after the absorption were also measured at the same conditions of the solubility measurements. It was found that density of aqueous solutions of sodium glycinate increases as the molar concentration increases and decreases with an increase in temperature. The solubilities of CO₂ are reported as loading capacity (mol CO₂/mol SG) as a function of partial pressure of CO₂ at the corresponding temperature. It was found that CO₂ solubility increases with increase in CO₂ partial pressure. It was also found that solubility of sodium glycinate solution decreases with increasing sodium glycinate concentration and temperature. The densities of aqueous sodium glycinate after absorption gave a higher value than that before absorption and increase with increasing pressure.