Absorption of co2 into aqueous tertiary amine/mea solutions

Abstract

AbstractAbsorption rates for CO2 into aqueous solutions of TEA, MDEA and blends of MEA with MDEA and TEA were measured in a stirred cell by a method similar to that used by Laddha and Danckwerts (1981). Second order rate constants for CO2‐TEA and CO2‐MDEA were obtained from the single amine data for temperatures in the range of 25‐60°C.A modified pseudo first order model based on the film theory is used to predict the rate of absorption of CO2 into mixed amine solutions. This model accounts for the variation of amine concentration in the film and assumes a shuttle mechanism for rate enhancement. Bulk liquid concentrations of the various species present are obtained from a simplified thermodynamic model. The model predicts absorption rates that are in agreement with experimental measurements.