Absorption of carbonyl sulfide in aqueous diethanolamine

In this study the kinetics of the aqueous-phase reaction between carbonyl s ulfide and diethanolamine is investigated. Data were obtained in aqueous po lyethylene glycol to test the nitrous oxide analogy method for estimating t he physical solubility and diffusivity of carbonyl sulfide in aqueous amine solutions. The experimental data indicate that the nitrous oxide analogy m ethod is applicable for carbonyl sulfide. The kinetics data are interpreted using the zwitterion mechanism. It is found that the limiting step in the reaction is the deprotonation of the zwitterion resulting in overall third- order kinetics. (C) 2000 Published by Elsevier Science Ltd. All rights rese rved.