Measurement of the reaction enthalpy of CO₂ in aqueous solutions with thermographic and gravimetric methods

In this work, a new concept for the approximate determination of the reaction enthalpy of the reaction between CO₂ and monoethanolamine (MEA) in aqueous solution was developed. For this purpose, a CO₂ gas stream was flowed into aqueous MEA solutions with different concentrations of 1 wt%, 2.5 wt% and 7.5 wt%. The weight difference ∆T, which is based on the increase in CO₂ bound by the MEA over time, was documented using a thermographic camera. The mass difference ∆m, which is also based on the increase in CO₂ bound by the MEA over time, was determined using a balance. By determining ∆T and ∆m, an approximate calculation of the reaction enthalpy is possible. The deviation from the values from the data known from the literature was less than 5% in all experiments.