A new absorbent for absorption of acid gases - propylene carbonate (WP) modified by triethanoloamine (TEA) was investigated The measurements of CO2 absorption rate were carried out by the laminar jet technique. It was shown that CO2 absorption in WP with addition of TEA can be regarded as a physical absorption process. The diffusion coefficient of CO2 in a new sorbent was measured in the temperature range of 10-40 degrees C (283-313 K) and correlated as a function of temperature and TEA concentration.