Optimal Absorbent Evaluation for the CO₂ Separating Process by Absorption Loading, Desorption Efficiency, Cost, and Environmental Tolerance

Abstract

The CO₂ absorption capacities of potassium glycinate, potassium sarcosinate (choline, proline), mono-ethanolamine (MEA), and tri-ethanolamine were evaluated to find the optimal absorbent for separating CO₂ from gaseous products by a CO₂ purification process. The absorption loading, desorption efficiency, cost, and environmental tolerance were assessed to select the optimal absorbent. MEA was found to be the optimum absorbent for separating the CO₂ and H₂ mixture in gaseous product. The maximum absorption loading rate was 0.77 mol CO₂ per mol MEA at temperature of 20°C and absorbent concentration of 2.5 mol/L, whereas desorption efficiency was 90% by heating for 3 h at 130°C. MEA was found to be an optimal absorbent for the purification process of CO₂ during gaseous production.

Keywords:

• Carbon dioxide
• Separating
• Mono-ethanolamine (MEA)
• Purification process
• Ionic liquids

Additional information

Funding

The authors gratefully acknowledge the financial support of the National Science Council of Taiwan (Grant No. NSC 101-2218-E-035-002-MY2, 102-2221-E-035-055, 103-2923-E-035-001-MY3) and Feng Chia University (Grant No. FCU-11G27150).