Polyethylenimine loaded nanoporous carbon with ultra-large pore volume for CO2 capture

- Nanoporous carbon with an ultra-large pore volume of about 4.28 cm3/g was prepared.
- Porous structure was preserved when the mass ratio of PEI to the carbon was 1.
- Over 85% CO2 can be captured in 2 min at 75 °C.
- Saturation amount was of 1.09 mmol/g when the mass ratio of PEI to the carbon was 1.
- The adsorption of the material toward CO2 remained constant in 5 cycles.

Nanoporous carbon with ultra-large pore volume was prepared by ball milling method, nanosized silica was used as hard template. Then polyethylenimine (PEI) with different content was loaded on the carbon, CO2 capture performance of PEI loaded carbon was investigated. Results indicated that the total pore volume and average pore diameter of the nanoporous carbon were about 4.28 cm3/g and 16.32 nm, respectively; the porous structure was maintained even when the mass ratio of PEI to the carbon reached 1. The high PEI loading amount and porous structure made more PEI load on the surface of the carbon, then CO2 capture rate and capacity were enhanced; in fact, over 85% of CO2 was captured in 2 min at 75 °C, which reached saturation in 5 min. The saturated CO2 capture amount was of 1.09 mmol/g when the mass ratio of PEI to the carbon was 1 at the CO2 partial pressure of 30%.