Zinc (II)-1,4,7,10-tetraazacyclododecane complexes catalyzed tertiary amine-based CO2 capture in a rotating packed bed

A novel tertiary amine-based CO 2 absorption process using zinc (II)-1,4,7,10-tetraazacyclododecane complexes (CN) as a catalyst in a rotating packed bed was proposed for energy-efficient CO 2 capture. The CN-catalysis reaction mechanism was first studied by density functional theory calculation, and the Gibbs Free Energy profile was established. Furthermore, the effects of various operation conditions for the tertiary amine-CN-CO 2 systems on the CO 2 removal efficiency ( η ), the overall gas-phase volumetric mass transfer coefficient ( K G a ), and the efficiency enhancement factor ( Φ ) were investigated. It was found that η and K G a with adding 4 wt% CN were 1–3 folds than those uncatalyzed. The absorption performance of CO 2 in DEEA solution with CN was superior to that in 10 wt% DEA solution. Finally, an artificial neural network model was established to predict K G a , and the predicted data agreed well with experimental results with the average absolute relative deviation of 5.07 %.