Revealing the Potential of Cyclic Amine Morpholine (MOR) for CO2 Capture Through a Comprehensive Evaluation Framework and Rapid Screening Experiments

The present study comprehensively evaluates the CO2 capture performance of morpholine (MOR) at concentrations of 2 M, 5 M, and 7 M, comparing its effectiveness against conventional amines, monoethanolamine (MEA) and 2-(methylamino)ethanol (MAE). The assessment criteria include CO2 absorption rate, desorption rate, cyclic capacity, regeneration energy consumption, and relative economic cost. Utilizing 13C Nuclear Magnetic Resonance (NMR) technology, we analyzed the variations in ion concentration of the amine solvents under different CO2 loadings to reveal the reaction mechanisms of MOR with CO2. Our results demonstrate that MOR outperforms MEA and MAE in CO2 capture performance, particularly excelling in desorption efficiency. At a concentration of 7 M, MOR exhibited a 357.86% increase in average desorption rate and a 46% larger cyclic capacity compared to MEA. Additionally, MOR showed a 33.33% reduction in regeneration energy consumption and a 7.89% decrease in relative economic cost. The comprehensive evaluation method developed in this study indicates that MOR, with its high thermal stability and low corrosivity, maintains excellent CO2 capture performance at high amine concentrations, suggesting it as a promising absorbent for industrial applications. The findings contribute to the optimization of amine-based CO2 capture technologies and provide a robust framework for the selection and assessment of amine solvents, paving the way for more sustainable and cost-effective carbon capture solutions.