| In order to realize the resource utilization of waste biogas residue generated by biogas project in the livestock farm, this study utilized the waste piggery biogas residue as the raw material to prepare biochar (BC), which was subsequently combined with peroxydisulfate (PDS) oxidation system for eliminating bisphenol A (BPA) from water. The effects of different pyrolysis temperatures, PDS concentrations, BC dosages, initial solution pH values, inorganic anions, organic matter and natural water on the removal of BPA were investigated. Results show that BPA removal followed the pseudo-first-order reaction kinetics model, and complete BPA could be removed within 30 min under the optimal reaction conditions: pyrolysis temperature of 600 °C (BC-600), 1.0 g·L-1 of BC-600 dosage, 0.5 mmol·L-1 of PDS concentration, 5 mg·L-1 of BPA concentration, and unadjusted solution pH (4.0). From electron paramagnetic resonance (EPR) analysis and radical quenching experiment results, it can be concluded that singlet oxygen 1O2 was the dominant reactive species during BPA removal. Additionally, the surface C=O group and defect structure on BC-600 surface was considered as the predominant active sites during reaction. Overall, preparation of biochar using agricultural waste biogas residue could utilize to combine with PDS for eliminating organic pollutants from water. |
