Degradation of tetracycline by activating persulfate using biochar-based CuFe2O4 composite

Biochar derived from Lentinus edodes (LBC) and CuFe2O4 (CuFe2O4@LBC) composites were prepared by the hydrothermal method, and were applied to activate persulfate (PDS) for degrading tetracycline (TC) in a wide pH range. The CuFe2O4@LBC composites were characterized by XRD, FTIR, SEM, and XPS. LBC-derived biochars greatly reduced the aggregation of CuFe2O4 particles and enhanced the catalytic performance of CuFe2O4. CuFe2O4@LBC catalyst could remove 85% of tetracycline within 100 min under visible light. In addition, the removal rate of TC reached 76% after five cycles, indicating that the composite had good stability and reusability. Simple classical quenching experiments suggested that the degradation of TC could be mainly attributed to •OH and •S [Formula: see text].