AIChE Journal, Vol.51, No.10, 2769-2777, 2005
Thermal effects of CO2 absorption in aqueous solutions of 2-amino-2-methyl-1-propanol
In this work, the process of carbon dioxide absorption is analyzed at high partial pressures, in aqueous solutions of 2-amino-2-methyl-1-propanol (AMP), with respect to the thermal effects involved. The experiments were carried out in a stirred tank reactor with a plane and known interfacial area. The variables considered were the AMP concentration and the temperature, within the ranges 0.1-3.0 kmol/m(3) and 288-313 K, respectively. From the results, we deduce that the absorption process of pure carbon dioxide into aqueous solutions of AMP takes place in the instantaneous nonisothermal regime at low concentrations, whereas at high concentrations the regime may be fast. In the experiments at low amine concentrations, we propose an equation, which not only relates the experimental results to the initial amine concentration but at the same time enables the evaluation of the rise in temperature in the gas-liquid interface. From the results at high concentrations, we determined a reaction order of one with respect to the amine and an expression for the kinetic constant valid throughout the entire range of temperatures and concentrations assayed: k = 4.8 X 10(12) exp(-8186.9/T). (c) 2005 American Institute of Chemical Engineers.