Solubility of Carbon Dioxide in 30 mass % Monoethanolamine and 50 mass % Methyldiethanolamine Solutions

The partial pressures of carbon dioxide (CO2) over a 30 mass % aqueous solution of monoethanolamine (MEA) and a 50 mass % aqueous solution of methyldiethanolamine (MDEA) were measured. The range of partial pressures of CO2 measured at 120 °C over 30 mass % MEA was from (7 to 192) kPa with loadings from (0.16 to 0.42). The partial pressures of CO2 ranging from (66 to 813) kPa with loadings from (0.17 to 0.81) over 50 mass % MDEA were also measured at the temperatures (55, 70, and 85) °C. An approximate value of the enthalpy of solution of CO2 in the aqueous MDEA solution was estimated using the solubility data.