Benzoguanamine based polyaminal carbon materials for CO2 capture application

•The porous carbon adsorbent material is prepared with and without KOH from N-rich polyaminal polymer.•Prepared porous carbon material have an excellent surface area (639 mg g−1) as well as total pore volume (0.28 cm3 g−1).•The heterogeneous nature of adsorbent and exothermic nature of the adsorption process is confirmed by isotherm models.•The spontaneity and physical interaction of adsorbent and CO2 are evaluated by Clausius-Clapeyron and Van't Hoff equations.