Synthesis of carbazole-based polymer derived N-enriched porous carbon for dyes sorption

A (N-vinyl carbazole)-based polymer, namely PPVK, was subsequently synthesized by free radical polymerization and oxidative polymerization. This material exhibits permanent porosity, good physicochemical stability, and plenty of nitrogen units. All these features make PPVK promising precursor for constructing N-enriched porous carbon. Using KOH as the activating agent, porous carbon material was prepared and its adsorption performance was also evaluated. Due to the high Brunauer–Emmett–Teller surface area (1832 m² g⁻¹) and abundant nitrogen atoms, the porous carbon, CPVK-800, displays adsorption capacity of 1074 mg g⁻¹ for Rhodamine B, which is far higher than that reported for commercial activated carbon (0.36 mmol g⁻¹). Kinetic investigations indicate that the adsorption behaviour follows the Langmuir isotherm model and pseudo-second-order kinetics. Besides the cationic dye rhodamine B, CPVK-800 also can be used to adsorption removal of anionic dye methyl orange, with uptake of 739 mg g⁻¹. Findings in this study highlight the potential of using carbonaceous polymer as an effective adsorbent for organic dyes.