Preparation of renewable porous carbons for CO2 capture – A review

A diversity of renewable wastes such as biomass and plastic can be employed for the synthesis of porous carbons, which have emerged as promising materials for CO2 capture under a wide range of conditions owing to their unique properties. Because of limited review articles in this field, this paper provided the recent progress and significant challenges in the synthesis of renewable porous carbons for CO2 capture with the objective of guiding future works on the CO2 abatement technologies towards a sustainable direction. Among the post-consumer plastics, PET has been widely used for the synthesis of porous carbons for effective CO2 capture because of its high carbon and oxygen content. In general, porous carbons derived from waste biomass and plastic are quite attractive for CO2 capture due to their tunable textural properties, simple synthesis methods and high CO2 adsorption capacities, which are closely associated with the structures and properties of porous carbons (e.g., microporous structure, heteroatoms doping). Particularly, the doped N species (e.g., pyridinic-N, pyrrolic-N) can transform the electronic state of the H atoms in the –CH and –NH groups on porous carbons to form hydrogen bonds between H and the O atom of CO2 molecule, thus for enhancing the CO2 adsorption. •Synthesis of various porous carbons from waste biomass and plastics is reviewed.•Porous carbons with narrow microporous structures are quite attractive for CO2 capture.•CO2 adsorption capacity is associated with the structures and properties of porous carbons.•Doping of heteroatoms (e.g., N) onto porous carbons enhances the CO2 capture. Future challenges on synthesis of sustainable porous carbons for CO2 capture are provided.