New Amines for CO₂ Capture. III. Effect of Alkyl Chain Length between Amine Functions on Polyamines Degradation

This study examines degradation of five tertiary polyamines (di- and triamines) in the presence of CO 2 or O 2 . They were chosen to identify the impact of alkyl chain length between amine functions. Degradation of aqueous amine solutions was evaluated at 140 °C under CO 2 or air pressure (2 MPa) in stainless steel batch reactors for 15 days. At the end of the run, most degradation products were identified by gas chromatography (GC)/mass spectrometry; amounts of remaining amine and its degradation products were determined with a quantitative GC method. The main degradation mechanisms are proposed, and some structure−properties relationships are established.