Design and synthesis of nitrogen-rich imine-based porous organic polymer as an efficient adsorbent for CO2 capture

Due to the many environmental problems caused by carbon dioxide, capturing this gas is of great importance. Since carbon dioxide, as a Lewis acid, interacts strongly with heteroatoms (such as N, O) and polar functional groups, we synthesized the Nitrogen-rich imine based porous organic polymer (NIPOP) through Schiff’s base condensation of bis-(4-formyl-2-methoxyphenyl) terephthalate and 2,4,6-trihydrazinyl-1,3,5-triazine in a mixture of xylene and dioxane in the presence of acetic acid as a catalyst. The structure of prepared NIPOP was elucidated by different methods, such as Fourier-transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), field emission scanning electron microscope (Fe-SEM), energy-dispersive X-ray spectroscopy (EDX), high-resolution transmission electron microscopy (HR-TEM), atomic force microscopy (AFM), thermogravimetric analysis (TGA), and Brunauer–Emmett–Teller (BET) surface area. The synthesized porous polymer has highly exposed active sites and high surface area which make good performance for gas adsorption. So, the NIPOP was used as an effective adsorbent for capturing of carbon dioxide. The NIPOP showed a good CO2 adsorption capacity of 74.2 cm3 g−1 and 49.5 cm3 g−1 at 273 and 298 °K, under 1 bar pressure, respectively. We think that the modification of prepared porous polymer and introducing various functional groups on this structure will improve its performance as an adsorbent for CO2 capture and other environmental contaminants.