Abstract
•The mesoporous carbon materials were prepared using a hard template method with varying rations of alkyl amines and CTC.•Nitrogen type and content in mesoporous carbon directly determines CO2 uptake behaviour.•Higher intrinsic nitrogen content lead to the selective low-pressure binding and large uptake of CO2 at high temperature.
Selective CO2 capture from a high temperature point source and its subsequent facile release is an important industrial challenge. It is well established that the nitrogen content can influence the CO2 uptake selectivity of carbon-based adsorbent materials. This work presents an example of how nitrogen type and content in mesoporous carbon directly determines CO2 uptake (and release) behaviour. Higher loadings of intrinsic nitrogen lead to increased isosteric heat of adsorption (Qst) values, with selective low- pressure binding and large uptake of CO2 at high temperature (75 °C). The process is reversible, only a mild vacuum exposure is sufficient to drive off the adsorbed CO2, with sustained performance without a noticeable loss in activity. The work highlights the scope of the fine tuning the application specific structure of the adsorbent materials for optimal use.