One-pot synthesis of high N-doped porous carbons derived from a N-rich oil palm biomass residue in low temperature for CO2 capture

Porous carbon materials have been widely used for CO2 adsorption, but their preparation was subject to conditions such as raw material cost, activator corrosion, and temperature. In this study, nitrogen-doped porous carbonaceous adsorbents were prepared in a low temperature region (400-550 degrees C) by one-step composite nitrogen doping method, using low-cost oil residue as raw materials and less corrosive NaNH2 as activator. The CO2 adsorption performances of the prepared N-doped porous adsorbents were systematically explored. The results showed that optimal oil residue-derived carbonaceous adsorbent owned excellent amount of CO2 adsorption up to 3.51 and 5.63 mmol/g at 298 and 273 K under 1 bar, respectively. It was discovered that the congenerous influences of porous structure, nitrogen content and V-n of the adsorbent affected their CO2 adsorption performances under 1 bar. Importantly, these oil residue porous carbonaceous adsorbent also was verified owning fine selectivity of the CO2 over N-2 (15.7), which attributed to its high V-n and nitrogen content. Furthermore, optimal sample OAC-500-2.5 owned medium Q(st) (21-26 kJ/mol), which was beneficial practical application. This work may inspire new sparks on novel nitrogen-doped adsorbent with inexpensive precursor, low activation temperature and simple preparative tactic, indicating that the nitrogen-doped sample is promising in the practical situation of CO2 adsorption.