NMR spectroscopic method for studying homogenous liquid phase reaction kinetics in systems used in reactive gas absorption and application to monoethanolamine–water–carbon dioxide

Abstract

An NMR spectroscopic method for measuring homogenous liquid phase reaction kinetics in systems that are used in reactive gas absorption processes is presented. In the kinetic experiment, carbon dioxide loaded and unloaded aqueous amine solutions are mixed such that no gas phase is involved. This

Speciation in CO2-loaded aqueous solutions of sixteen triacetoneamine-derivates (EvAs) and elucidation of structure-property relationships

“…Due to the lower volatility, the molecule size of the amine can be reduced which lowers the dynamic viscosity and enhances the mass transfer of CO 2 . Additionally, hydroxy groups form alkylcarbonates which is an additional reaction pathway for the absorption of CO 2 that should increases the rate of reaction of CO 2 compared to similar systems without that reaction [71]. If high mass transfer and low volatility is absolutely essential in the purification task, the addition of hydroxy groups may be considered.…”

Estimation of the Amount of CO2 Chemically Absorbed in Real Time by Measuring the Electrical Conductivity Variation of Monoethanol-Amine Aqueous Solutions

“…Additionally, some studies have also investigated the feasibility of the process via modeling and simulation. − Recently, however, many papers have focused on the performance of the hybrid solutions manufactured by blending MEA with other amines or additives to reduce the energy penalty of the system. − In addition, other works specifically report the reaction rate, physical and chemical properties of MEA solution under the various absorption conditions, as well as its thermodynamic values. , Prior studies have shown that the reaction mechanism of CO 2 absorption using MEA solution as the solvent is known to be based on two models: zwitterion and termolecular. The overall reaction of the two mechanisms is reported to be a second-order reaction in terms of CO 2 and MEA concentration, and the reaction constants are presented to range from 1435 to 94,444 L/(mol·s) as estimated under various experimental conditions such as temperature, MEA concentration, CO 2 concentration, and reactor type. − Using these reaction rates, the accumulated-chemical CO 2 absorption capacity (or amount) until the arbitrary reaction time (CAC AC ) can be estimated under certain conditions throughout the absorption. The accumulated-total CO 2 absorption capacity (or amount) until time (CAC AT ) during the reaction includes the total amount of physically absorbed CO 2 .…”