Solubility and Diffusivity of CO₂ in Triethanolamine Solutions

The objective of this study was to measure directly the physical solubility and diffusivity of CO 2 in aqueous triethanolamine (TEA) solutions via the protonation method. The method is based on the protonation of TEA solutions by HCl prior to contacting the solutions to CO 2 to eliminate the solutions reactivity with CO 2 . The properties were measured for concentrations of 10, 20, and 30 mass% TEA in the solution over the temperature range (20−60) °C. The volumetric and the wetted sphere methods were used to measure the solubility and diffusivity, respectively. The measured data of solubility and diffusivity were well fitted versus temperature by an exponential form. The measured properties by the protonation technique and the available literature values measured by the “N 2 O analogy” method were compared. Good agreement between the two methods was found.