Methyl-diethanolamine degradation - Mechanism and kinetics

Methyl-diethanolamine (MDEA) degradation reactions between aqueous solutions of MDEA and CO2 have been carried out in a 600 mL stirred autoclave under the following conditions: initial MDEA solution concentration 20-50 mass%, solution temperature 100-200 degrees C, CO2 partial pressure 1.38-4.24 MPa. It was found that MDEA degrades quite rapidly (although more slowly than diethanolamine under comparable conditions) at elevated temperatures and CO2 partial pressures. Degradation products are identified by gas chromatography and mass spectrometry (GC/MS). An MDEA degradation reaction mechanism and kinetic model predicting concentration changes is proposed and verified.