Simultaneous functionalization and magnetization of biochar via NH ambiance pyrolysis for efficient removal of Cr (VI).

Enhancing biochar adsorption capabilities and recollection ability is essential for efficient biochar application. In this study, Nitrogen-doped magnetic biochar was prepared via one-step heating of FeCl-laden agar biomass under NH environment. Synthesized magnetic biochar ABF-N shows a maximum Cr (VI) adsorption capacity up to 142.86 mg g, outperforming that of magnetic biochar and many other previously reported materials. Moreover, a significant increase of magnetic properties obtained by NH ambiance pyrolysis enables easy separation of the adsorbent from the solution after treated with Cr (VI). The physiochemical properties of composites characterized by SEM, EDS, XRD, XPS, VSM, BET surface and pore, Elemental content, and FTIR analysis. The NH ambiance pyrolysis confirmed as an efficient process for surface modification, increased magnetic properties and activated N-functional groups. The Langmuir isotherm model and pseudo-second-order model are applicable for describing adsorption behavior. The thermodynamic study shows that the adsorption was spontaneous and endothermic. The present results warrant the application of simultaneous functionalized and magnetized biochar for Cr (VI) contaminated wastewater treatment.