An anchoring-separation strategy using arginine for fabricating highly active iron-based catalyst toward organic pollutants removal

Designing highly efficient iron-based catalysts with adsorption and degradation of pollutants is a great challenge in the field of environmental remediation. Herein, a dual strategy of anchoring-separation was adopted to prepare novel iron-based nitrogen doped porous carbon catalysts (Fe-pNC). Arginine was innovatively selected as the anchoring agent to coordinate with Fe 3+ and even form oligomers with glucose, which was conducive to the dispersion of iron species during high-temperature pyrolysis. Fe-pNC achieved high iron loading of 16.48 wt% and large specific surface area of 480.19 m 2 /g. The Freundlich model determined a maximum SMX adsorption capacity (Qm) of 82.38 mg/g for Fe-pNC, surpassing most of recently reported SMX adsorbents. Interestingly, even after multiple PMS regenerations, Fe-pNC still exhibited excellent adsorption performance. Surprisingly, Fe-pNC exhibited better adsorption performance at low temperature, achieving 90.58 % adsorption rate at 0 °C. More importantly, the Fe-pNC/PMS system achieved 99.11 % SMX removal in 15 min with a superior apparent rate constant (k obs ) of 0.54 min −1 . Of particular significance, Cl − markedly enhanced the catalytic efficacy of the Fe-pNC for SMX removal, remarkably enhancing the catalytic degradation performance even at high concentrations. Quenching experiments combined with electron paramagnetic resonance (EPR) detections demonstrated that single-linear oxygen 1 O 2 ) and superoxide radicals (O 2 •− ) were the major reactive oxygen species (ROSs). This study provides a significant guidance into developing efficient iron-based catalysts for adsorption and removal of organic pollutants.