High energy consumption during solvent regeneration remains the primary barrier to the widespread deployment of amine-based CO 2 capture. This study presents a synergistic approach by integrating Fe nanoparticles anchored on N-doped carbon spheres (Fe–N–C) with a non-aqueous solvent consisting of 2-(butylamino)ethanol (BAE) and diethylene glycol monomethyl ether (DEGMME). Characterization via XPS and Raman spectroscopy confirmed the presence of active Fe–N x coordination sites and a high density of structural defects (I D /I G = 0.85), which facilitate the catalytic CO 2 desorption. The Fe–N–C catalyst (0.2 wt%) demonstrated profound kinetic enhancement across both aqueous and non-aqueous systems. In aqueous MEA and BAE benchmarks at 90 °C, the catalyst increased CO 2 desorption rates by up to 420%, reducing the relative regeneration heat duty by ~26%. For the BAE/DEGMME nonaqueous system, the catalyst enabled efficient regeneration between 70 and 90 °C, increasing the desorption rate by nearly 380%. Notably, at a reduced temperature of 70 °C, the catalytic nonaqueous system achieved a ~ 73% regeneration efficiency, yielding a ~ 68% reduction in relative heat duty compared to the 30 wt% aqueous MEA benchmark. 13 C NMR and ATR-FTIR speciation analyses confirmed that Fe–N–C facilitates the decomposition of carbamate intermediates, lowering the thermal threshold for CO 2 release. The catalyst exhibited robust structural and functional stability over 20 cycles. This work demonstrates that integrating tailored catalytic surfaces with selected non-aqueous solvents provides a viable pathway for intensifying carbon capture while utilizing low-grade thermal energy.
Bhatti et al. (Mon,) studied this question.