Carbazole-tagged pyridinic microporous network polymer for CO2 storage and organic dye removal from aqueous solution

Abstract

A microporous organic polymer (Cz-pyr-P) was prepared from a monomer of pyridine-imides, flanked by four carbazoles, and its application as an adsorbent for both CO2 and methylene blue dye in wastewater was investigated. The polymer was synthesised by oxidative polymerisation facilitated by FeCl3 and comprehensively characterised using routine spectroscopic, thermal, textural, and morphological analyses. With a high surface area of 1065 m2/g and a median pore width of 8.06 Å, the nitrogen-enriched Cz-pyr-P reversibly adsorbed 19.41 wt% (273 K) and 12.78 wt% (295 K) CO2 at 1 bar, with a good isosteric heat value of CO2 adsorption (28.5 kJ/mol). For the removal of methylene blue dye from wastewater, Cz-pyr-P exhibited excellent partition coefficient of 380.10 mg/g μM with an equilibrium time of 6 min which is shorter than previously reported values for other materials. The results indicate that Cz-pyr-P with desirable functionality could be utilised for reaching CO2 emission reduction targets as well as for wastewater treatment.