Total pressure and CO2 solubility at high temperature in aqueous amines

Total pressure was measured in CO2 loaded aqueous monoethanolamine, piperazine, 1-methyl-piperazine, 2-methyl-piperazine, and diglycolamine® at 82 to 191 °C from 115 to 2819 kPa. CO2 solubility is estimated from these data. Empirical models have been developed to predict the CO2 partial pressure of these amine solutions from 40 to 160 °C. The heat of CO2 absorption derived from these models varies from 66 kJ/mol for piperazine and its derivatives to 71 and 73 kJ/mol for monoethanolamine and diglycolamine and does not vary significantly with temperature.