A new absorbent for carbon dioxide and hydrogen sulphide absorption process

The results of investigations on the process of CO2 and H2S absorption in a new absorbent, propylene carbonate (PC) modified by triethanoloamine (TEA), are presented. The data on CO2 and H2S solubility, as well as the results of measurements of the absorption rate of these gases in the TEA-propylene carbonate solution are reported. The measurements were carried out in the range of parameters most interesting in terms of the commercial application of the process. The data on CO2 and H2S solubility in the TEA-propylene carbonate solution are presented in the form of correlation equations as functions of gas partial pressure, temperature and TEA concentration. CO2 and H2S diffusion coefficients obtained in kinetic investigations are correlated with temperature and TEA concentration. The mechanism of CO2 and H2S absorption in the TEA-propylene carbonate solutions is explained. Application of the propylene carbonate with TEA as an additive in the CO2 absorption process has been tested in a pilot plant and will be offered as a commercial process. (C) 1998 Elsevier Science S.A.