Waste valorization of pig manure into cobalt biochar for pathway-selective peroxymonosulfate activation and water...

The sustainable valorization of livestock waste into functional materials offers a dual solution to agricultural waste management and water pollution challenges. In this study, pig manure (SW) was valorized into a cobalt-loaded biochar (Co-BC) through a one-step pyrolysis process, enabling highly selective non-radical (¹O₂-dominated) activation of peroxymonosulfate (PMS) for aqueous contaminant removal. The manure-derived biochar, characterized by abundant oxygen-containing functional groups and hierarchical porosity, stabilized dispersed cobalt species and facilitated selective oxidation via a non-radical route. The Co-BC/PMS system exhibited rapid bisphenol-A (BPA) degradation kinetics (k_obs = 0.3864 min^-1) and excellent catalytic performance, achieving 99.75% bisphenol-A (BPA) removal efficiency within 10 min under optimal conditions (0.2 g⋅L^-1 Co-BC and 1 mM PMS). The system exhibited robust performance over a broad pH range (4.00-10.00) and in complex water matrices. Combined experimental and theoretical analyses suggest that the enhanced electron transfer capability of Co-BC facilitates efficient PMS activation with high pathway selectivity. Along with high reusability and low toxicity, convenient magnetic separation and stable operation in a continuous-flow reactor (stable removal over 24 h) further demonstrate the practical feasibility of the material. This work presents a waste-to-resource strategy for environmental catalysis and highlights the potential of livestock manure-derived materials for water treatment applications.