Reaction mechanism and kinetics of aqueous solutions of 2-amino-2-methyl-1,3-propandiol and carbon dioxide

The mechanism and kinetics of the reaction between aqueous solutions of CO2 and a sterically hindered primary amine, 2-amino-2-methyl-1,3-propandiol ( AMPD) was investigated at 278-303 K by using a stopped-flow technique. It w as found that the reaction order according to power law kinetics was betwee n 1.26 and 1.33 for amine concentration range of 0.025-1.600 kmol m(-3). Th is order was slightly higher than that of 2-amino-2-methyl-1-propanol (AMP) , which was reported previously for similar conditions [E. Alper, Reaction mechanism and kinetics of aqueous solutions of 2-amino-2-methyl-1-propanol and carbon dioxide, Ind. Eng. Chem. Res. 29 (1990) 1725.], and was therefor e considered to be further evidence that the reaction takes place according to zwitterion intermediate mechanism. The kinetic rate parameters for aque ous AMPD solutions were obtained for 273-303 K and over the concentration r ange of 0.025-1.600 kmol m-3 of AMPD according to this mechanism. (C) 1999 Elsevier Science S.A. All rights reserved.