CO2 absorption effect on electric conductivities for butylethanolamine and methyldiethanolamine aqueous solutions at 313 K

Abstract

The CO2 absorption, density, viscosity, pH, and electric conductivity were measured for aqueous solutions of butylethanolamine (BEA) and methyldiethanolamine (MDEA) at 313.2 K under atmospheric pressure. The CO2 loading [mol-CO2/mol-amine] of aqueous BEA and MDEA solutions studied decreased with increasing BEA and MDEA concentration. The CO2 loading of an aqueous BEA solution was larger than that of an aqueous MDEA solution in the range of 10 - 40 wt% amine concentration. The electric conductivity of the aqueous BEA solution is larger than that of aqueous MDEA solutions, and the amine concentration dependence of the electric conductivities for both solutions studied showed maxima at 10 wt%. The electric conductivities of BEA and MDEA solutions after CO2 absorption increased with increasing CO2 loading. The CO2 loading dependence of the electric conductivity was correlated with a linear function. It may be suggested that the correlation coefficients predict the CO2 loading and amine concentration in solution at 313.2 K.