Guanidine-based deep eutectic solvents in CO2 capture process

ARATA BADANO JOAQUIN; FEDERICO GOMEZ; JORGE G. URANGA

Venecia

Congreso; XV Porgraduate Summer School on Green Chemistry; 2023

IUPAC

Extensive research has been conducted on carbon dioxide (CO2) capture, utilization, and storage (CCUS) to address climate change. Among the various methods explored, physical and chemical absorption has emerged as the preferred options due to their operational simplicity. Previous studies have shown the effectiveness of amines as liquid absorbents for CO2 capture. However, the use of amines presents several challenges, including high volatility, degradation at higher temperatures, energy-intensive solvent regeneration, corrosiveness, and toxicity. Deep Eutectic Solvents (DESs) have attracted considerable attention due to their interesting properties, such as low volatility, task specificity, and high thermal and chemical stability. DESs are formed through hydrogen bond interactions between hydrogen bond donors (HBDs) and acceptors (HBAs) and offer significant advantages such as a simple synthesis process, low cost, and tunable structures.In the present study, different DES have been prepared by mixing guanidine hydrochloride (GuaHCl) as HBA with ethylene glycol (EG), glycerol (Gly), propylene glycol (PG), polyethylene glycol 400 (PEG400), 1,3 propanediol (1,3-PDOH) and butylamine (ButNH2) as HBDs. The solubility of CO2 was measured gravimetrically at 25 °C and at 10 bar. Physical and chemical absorption were identified by FT-IR spectroscopy.