Amino acid salts for CO2 capture at flue gas temperatures

Abstract

An amino acid salt, potassium taurate has been chosen as a high temperature absorbent in this study due to its low volatility and high absorption rate. The densities and viscosities of 2M-6M taurate solution have been determined over the temperature range from 293K to 353K. The CO2 solubility of taurate solutions has been measured using a stirred-cell reactor. It has been found that the CO2 solubility of taurate solutions is comparable to that of alkanolamines at high temperature. The absorption rate of CO2 into CO2 free and CO2 loaded taurate solutions were obtained using a wetted-wall column. The KG of 4M taurate at 353K is similar in magnitude to the KG of 5M MEA at 313K. It has also been found that the KG of taurate decreased with increased CO2 loading, but the values for KG of taurate solutions are still comparable to CO2 loaded 5M MEA solution.