One-pot synthesis of melamine-based porous polyamides for CO2 capture

Porous organic polymers (POPs) with high Brunauer-Emmett-Teller (BET) surface area (S-BET) and plentiful heteroatoms are promising for CO2 capture and separation. Herein a series of melamine-based porous poly-amides were synthesized from melamine and binary/ternary benzoic acid by one-pot polycondensation strategy. These polymers have considerably high S-BET (up to 521 m(2)/g) and enriched nitrogen (13.8-44.9 wt%). Importantly, they possess noteworthy CO2 uptake (0.53-2.9 mmol/g at 273 K and 1 bar), the synergistic effect of predominant microporosity and abundant nitrogen are beneficial. Moreover, they have moderate isosteric heats (Q(st)) (29.5-43.7 kJ/mol) and acceptable CO2/N-2 selectivity (IAST: 31.6-277.8), which are highly relevant to the micropore volume, micropore area, and nitrogen content.