Preparation of nanoporous carbons with hierarchical pore structure for CO2 capture

Nanoporous carbons with a hierarchical pore structure were prepared by a combination of hard-templating of a thermosetting phenolic resin containing silica nanoparticles, pyrolysis and KOH activation. The influence of the amount of KOH on the pore structure of the templated and activated carbons was investigated by N2 adsorption and the effect of pore structure on the CO2 adsorption capacity was investigated by thermogravimetric analysis. Results indicated that KOH activation promoted the formation of micropores and small mesopores for the templated carbon. The utilization ratio of mesopores for the capture of CO2 is high compared with that of micropores. The porous carbon prepared under a mass ratio of KOH to templated carbon of 2∶1 has both developed mesopores and micropores, and has a largest adsorption capacity for CO2 among all samples investigated.