Benzoguanamine based polyaminal carbon materials for CO2 capture application

Abstract

In this work, the porous carbon materials are prepared by carbonizing benzoguanamine based polyaminal with and without KOH at 700 °C in N2 atmosphere. The functional group and crystalline nature of the prepared materials are characterized using FT-IR and powder-XRD analysis. The carbonized polyaminals polymer contains various types of nitrogen moieties such as pyridinic-N, pyrrolic-N and quaternary amine-N are established by XPS spectra. The porous carbon material (P-BA-7b) prepared by activating polyaminal polymer with KOH shows the high surface area (639.48 m2 g−1) and total pore volume with microporous by N2 sorption profiles. The KOH activated carbonized material is exhibited a significant CO2 uptake capacity (2.84 mmol g−1 at 273 K) and selectivity (39.6 at 273 K) over N2. The thermodynamic data of the materials demonstrate the spontaneity of the CO2 adsorption process. The enthalpy (-ΔH0) and heat of adsorption (-Qst) results suggest both chemical and physical interactions of the CO2 molecule and adsorbent, but the physisorption is more dominated. Hence, carbonized materials (nitrogen-containing) with good surface area and CO2 capture with selectivity are promising candidates for CO2 capture application