Absorption rates of gaseous CO 2 into aqueous N-methyldiethanolamine (MDEA) solutions were measured in a quiescent, inverted-tube diffusiometer by monitoring the rate of pressure drop. The absorption rate was found to be insensitive to the diffusion coefficient of CO 2 in solution but very sensitive to the diffusion rate of bicarbonate and protonated MDEA ions. Evidence also suggested that chemical reaction equilibrium is rapid relative to diffusion. A numerical model was developed on the basis of these observations. The model was used to regress diffusion coefficients of bicarbonate and protonated amine, which must be equivalent by electroneutrality arguments, from measured absorption rates. Complete modeling of the absorption process also required data for the diffusion coefficient of MDEA in water. These were measured using a Taylor dispersion apparatus. CO 2 absorption rates and diffusion coefficients of bicarbonate and protonated MDEA were obtained at 298.2 K and 318.2 K in solutions containing 20, 35, and 50 mass % MDEA in water.
A static method was used to measure the critical temperature,
critical pressure, and critical volume on
three compounds: ethyl thioacetate, methoxybenzene, and
2-methoxyethanol. A flow method was used
to measure the critical temperature and critical pressure on eleven
compounds: acrylonitrile, 1,4-butanediol, 2-(2-butoxyethoxy)ethyl acetate, γ-butyrolactone,
cyclohexanol, 1,2-ethanediamine, 2-(2-ethoxyethoxy)ethanol, 2-(2-ethoxyethoxy)ethyl acetate,
1-methoxy-2-propanol, 2-(2-methoxyethoxy)ethanol,
and 2-nonanone.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.