Characterization of 2-piperidineethanol and 1-(2-hydroxyethyl)pyrrolidine as strong bicarbonate forming solvents for CO2 capture

The solubility of CO2 in the aqueous solutions of 50 mass% 2-Piperidineethanol (2-PPE) and 40 mass% 1-(2-Hydroxyethyl)pyrrolidine (1-(2HE)PRLD) was measured at temperatures from 40 to 120 °C at CO2 loading from 0.04 to 0.8 mol-CO2/mol-amine. The density and viscosity of unloaded and CO2-loaded solutions were measured at temperatures between 20 and 80 °C and fitted to simplified correlations. Based on a thermal degradation test, both solvents were found to be more stable and less corrosive than 30 mass% MEA. However, oxidative degradation tests indicate that the 1-(2HE)PRLD degradation rate is lower than that of 30 mass% MEA while 2-PPE degrades much faster. From the environmental aspect, both solvents are found to be non-toxic and biodegradable in fresh water. These experimental data will be used for estimation of the energetic and environmental potential as solvents for CO2 capture.