Results of an extensive research program, aimed at finding new, more efficient activators of carbon dioxide absorption into aqueous carbonate/bicarbonate solutions are presented. Both single amines (2-ethyl-aminoethanol, 2-isopropyl aminoethanol, piperazine, tetraethylenepentamine, N-ethyl-piperazine and glicyne) and amine mixtures have been investigated. Absorption rate measurements were conducted in a laminar-jet absorber. Reaction rate constants for the particular activators were determined. Mixtures of aliphatic amines with cyclic amines, as well as mixtures of cyclic amines with cyclic amines were found to exhibit synergetic effect. Such amine mixtures might be used as new promoters for CO2 absorption in carbonate solutions in the modified Benfield process.
In the paper the results of measurements of CO2 absorption rate in aqueous potassium carbonate solutions containing cyclohexylamine, diethanolamine, 2-methylaminoethanol and triethylenetetramine as activators have been presented. Enhnancement mass transfer factors as well as reaction rate constants have been determined. Results show that among the tested activators triethylenetetramine and 2-methyl-aminoethanol may be used (instead of diethanolamine) as new promotors in a modified BENFLIELD process.