Oxidative degradation of 2-ethanolamine: The effect of oxygen concentration and temperature on product formation

Oxidative degradation experiments on 2-ethanolamine (MEA) were performed at four different oxygen concentrations and at two temperatures. MEA loss and degradation product build-up were measured. Increasing the temperature from 55 to 75 °C was shown to have higher impact on the MEA loss than increasing the oxygen concentration from 21 to 98%. Liquid end sample analyses were performed for all experiments and overall nitrogen balance tests were conducted for the experiments at 21% O2 (run 2), 50% O2 and 98% O2. Analysis of liquid and gas phase ammonia and MEA in the solvent was found to give a good overall picture of degradation in the MEA system. The degradation products formed at the different oxygen concentrations were the same as described in earlier literature. However, it was found that oxygen affects the formation of the individual degradation products differently. At 75 °C the development of degradation product concentrations with time was more complex. Laboratory reaction experiments were used to verify the formation of certain degradation products from some of the suggested mechanisms.