Improved CO₂ Capture and Catalytic Hydrogenation Using Amino Acid Based Ionic Liquids

A series of alkyl ammonium (or imidazolium) based ionic liquids was tested as novel and potentially green absorbent for CO₂ capture and utilization. By exploiting various amino acids as counter ions for ionic liquids, CO₂ capture and hydrogenation to formate occur with high activity and excellent productivity utilizing arginine. The reaction was easily scalable without any significant drop in formate production, and the catalyst was reused for five consecutive runs leading to an overall TON of 12,741 for the formation of formate salt.