Utilization of tertiary amine solutions and ultrasound irradiation for CO2 desorption at low temperature in a CCS process

• Published in: Japanese Journal of Applied Physics Vol. 60; no. SD
• Main Authors: Okawa, Hirokazu, Ito, Hiroyasu, Fujiwara, Tatsuo, Kitamura, Yuya, Kato, Takahiro, Sugawara, Katsuyasu
• Format: Journal Article
• Language: English
• Published: Tokyo IOP Publishing 01-07-2021; Japanese Journal of Applied Physics
• Subjects: Carbon dioxide; CCS; Desorption; Irradiation; Low temperature; Tertiary amine solution; Triethanolamine; Ultrasonic imaging; Ultrasound
• ISSN: 0021-4922; 1347-4065
• DOI: 10.35848/1347-4065/abe2e8

This study used three tertiary amine solutions as a CO2 absorbent. Ultrasound can desorb CO2 from CO2(aq) and H2CO3 species at low temperature. Tertiary amine solution with lower pKa created CO2 adsorption equilibrium at lower pH related to a higher CO2 desorption amount using 28 kHz ultrasound because the lower pH environment would increase the existence ratio of CO2(aq). Triethanolamine (TEA) with lowest pKa (7.85) showed the highest CO2 desorption ratio of 48% for 30 min irradiation at 25 °C. The CO2 absorption-desorption capacity of TEA by reuse was evaluated and found to keep the first capacity for three cycles.