SOLID CO_2 ADSORBENT BASED ON LINEAR POLYETHYLENIMINE AND NANO-SILICA FOR IMPROVED DESORPTION KINETICS

摘要

Linear polyethylenimines (LPEIs) with different molecularrnweights impregnated onto nano-sized hydrophilic fumed silica werernshown to be effective solid adsorbents for CO_2 capture from variousrngas sources, including the air. These solid adsorbents are able tornadsorb selectively and reversibly CO_2 with adsorption capacities ofrnup to 155 mg CO_2·g-1. Desorption of the adsorbed CO_2 occurs rapidlyrnat mild temperatures (50 to 100 ℃). Compared to branched PEI, theyrnoffer faster desorption kinetics, which is advantageous for fastrnadsorption/desorption cycling.