Kinetics and mechanisms of the reactions of carbon dioxide with alkanolamines: a discussion concerning the cases of MDEA and DEA

On the kinetics between CO2 and alkanolamines both in aqueous and non-aqueous solutions—I. Primary and secondary amines

“…However, the deviation of the results of a few studies (Hikita et al, 1977a;Barth et al, 1984) still remains unsatisfactorily. In order to evaluate the zwitterion-mechanism in more detail, additional experiments have been carried out in this study over a wider range of conditions and solvents.…”

“…By this approach their kinetic model was also able to obtain a good agreement with the results of Jensen et al (1954) and J&gensen (1956). Barth et al (1984) re-examined his results and concluded that the Blauwhoff approach was the closest to his results with respect to both reaction order and reaction rate constant. In spite of this good agreement a discrepancy still remains between the Blauwhoff approach and the results of Hikita et al (1977a).…”

“…However, if other Table 9. Fitted values of kinetic constants for the system CO,-DEA-water at 298 K experimental techniques were used, in which the solubility and diffusivity were not required to interpret the experiments, the agreement is less satisfactory (Hikita et al, 1977a;Barth et al, 1984 Sada et al (1977Sada et al ( , 1978 and Haimour and Sandal1 (1984) except for DEA solutions. The experimental results for DEA at 298 K of Blauwhoff et al (1984) have therefore been reevaluated with the new data for the solubility and diffusivity of C02.…”

“…10 the results of Hikita et al (1977a,b) and Barth et al (1984) are compared with the recalculated results of Blauwhoff et al (1984) for solutions with a 1 mol. m-3 CO2 liquid load.…”

The reaction between CO2 and diethanolamine at 298 K

“…Int 1 r Barth et al, 1984;Blanc and Demarais, 1984;Blauwhoff et al, 1984, Sada et al, 1985Tseng et al, 1988) no general agreement on the reaction rate constants exists. However, the zwitterion mechanism proposed originally by Caplow (1968) is uniformly accepted as the reaction mechanism.…”