CO2 capture using amino acid sodium salt mixed with alkanolamines

Abstract

Sodium aliphatic diamine sulphonate (NaADS) was found to be an appropriate amino acid salt to mix with piperazine (PZ) and diethylenetriamine (DETA) to capture CO2 after the absorption of CO2 and regeneration of absorbent tests in a continuous mode in which two rotating packed beds were used for CO2 absorption and absorbent regeneration. Though the viscosity of the aqueous mixture PZ/DETA/NaADS (15/15/10 wt%) was 1.48 times PZ/DETA (15/15 wt%), the CO2 capture amount by PZ/DETA/NaADS was similar to that by PZ/DETA due to the presence of high momentum in an RPB and more amines provided by NaADS in solution. The dissolved oxygen in PZ/DETA/NaADS (15/15/10 wt%) was observed to be 52.5% lower than PZ/DETA (15/15 wt%) and 59.5% lower than MEA (30 wt%). At the regeneration condition of 2 atm and 120 °C, 7.3% less energy required to regenerate PZ/DETA/NaADS compared with PZ/DETA (15/15 wt%) and 9.9% less energy than MEA (30 wt%).