Preparation of novel iron-bearing biochar derived from Calotropis procera biomass for aromatic organic pollutant removal via persulfate activation.

In this work, a new carbonaceous source, Calotropis procera biomass, was employed in the preparation of biochar for use as an iron-bearing catalyst support. The iron-bearing biochar (Fe/BC) was used to degrade phenol, a contaminant widely found in numerous industrial effluents, via the persulfate activation route. A 2³ experimental design with three central points was employed to optimize the process parameters, achieving a high phenol removal rate of 91.13% using 13 mM sodium persulfate dosage, 7 g L⁻¹ catalyst concentration, and pH = 3.0. The effective performance of the Fe/BC sample can be attributed to the synergistic effect between porosity, dispersity in the aqueous medium, and the presence of oxygen-containing functional groups. Additionally, the material proved effective over three successive cycles, demonstrating good stability for reuse purposes. Therefore, the material prepared in this work contains intrinsic properties that make it a promising catalyst for activating persulfate towards phenol degradation in water environments.