Rationalizing Product Formation in Piperazine Degradation: A Computational Study

Knowledge of the origins of degradation products observed during amine degradation is crucial to developing new, more efficient amines for future carbon-capture plants. Here, we report on a series of density functional theory (DFT) calculations rationalizing the routes to products observed from piperazine degradation studies. Experimentally viable routes to the formation of 1-(2-aminoethyl)-2-imidazolidone (AEI), N-(2-aminoethyl)­piperazine (AEP), 1-[2-[(2-aminoethyl)­amino] ethyl] piperazine (AEAEPZ), N-(2-hydroxyethyl)­piperazine (HEP), and 1,1′-(1,2-ethandiyl)­bis-piperazine (PEP) are presented. The modeling studies reported here are essential for the construction of chemical kinetic mechanisms, which can predict the byproduct formation from thermal and oxidative degradation.