Functionalized Carbon Spheres for Energy-Efficient CO2 Capture: Synthesis, Application, and Reaction Mechanism

Catalyst-facilitatedamine regeneration provides exciting new opportunitiesto fulfill the Paris Climate Accord by developing an energy-efficientand economically feasible CO2 capture process. However,finding inexpensive and easy-to-synthesize catalysts, along with understandingthe catalytic desorption mechanism, is imperative. Herein, we developan environmentally friendly glucose-derived carbon sphere nanocatalystwith isethionic acid functionalization which can optimize the CO2 desorption rate of CO2-loaded aqueous monoethanolamine(MEA) solutions at & SIM;86 & DEG;C. The desired physicochemicalproperties of the developed materials can be readily tuned by varyingthe amount of isethionic acid used for functionalization. The synthesizedcatalysts accelerated the CO2 desorption rate by up to108% and reduced the heat duty by & SIM;10.8% compared to the traditionaluncatalyzed MEA regeneration. NMR analysis unveils that unlike conventionalregeneration where carbamate stability hinders the low-temperatureCO(2) desorption, the prepared catalysts can decompose carbamateat much lower temperatures and thereby reduce the energy consumptionof amine regeneration. These catalysts can be readily separated andare stable in cyclic uses, making them suitable for industrial-scaleapplications. Catalyst-facilitated solvent regeneration at 86 & DEG;Ccan allow the regenerator to use low-grade industrial waste heat,which may enable efficient CO2 capture facilities to beinstalled at a wide range of industrial sites to achieve net zeroemissions by 2050. Environmentallyfriendly glucose-derived carbon sphereswere functionalized and ultimately used to accelerate the CO2 desorption from amine solution.