Effect of the Feedstock Type on the Volumetric Low-Pressure CO2 Capture Performance of Activated Carbons

Abstract

Activated carbons (ACs) display attractive gravimetric performance for CO2 capture, but it is unclear which carbon precursor suits preparation of ACs with high adsorption performance on a volumetric basis. Thus, we prepared ACs from five feedstocks (bamboo, rice husk, peanut shell, coconut shell, and anthracite) to study impacts of the feedstock type on the densities, volumetric pore parameters, and volumetric CO2 adsorption performance of ACs. The feedstock type was found to affect tap density of ACs, mainly because ACs possessed different macropore volumes. Because of the influence of tap density, the decreasing order of ACs for volumetric pore parameters was different from that for the corresponding gravimetric parameters. When AC was expected to display a high volumetric fine micropore volume (V<0.7 nm,v and V<1 nm,v), its tap density and gravimetric fine micropore volume should be both high. The feedstock type affected the volumetric CO2 uptakes of ACs at 0.15 and 1 bar, mainly because it changed vol...