Photo-activation of persulfate and hydrogen peroxide by humic acid coated magnetic particles for Bisphenol A degradation.

• The effect of HA coating on MPs was studied in photo-Fenton-like process. • Humic acid coating enhances the H 2 O 2 and S 2 O 8 2− activation for BPA degradation. • Reactive species were identified (OH and SO 4 –) through scavenging experiments. • The recycling and reuse of MP/HA show no loss of activity. • The efficiency of MP/HA was tested in real wastewater sample. Magnetic particles (MPs) coated with humic acid (HA) prepared under anoxic atmosphere were tested as heterogeneous photo-Fenton catalyst for the activation of hydrogen peroxide (H 2 O 2) and persulfate (S 2 O 8 2−) using Bisphenol A (BPA) as a model pollutant. The role of HA coating, pH value and H 2 O 2 /S 2 O 8 2− concentration were investigated. A positive contribution of HA coating on H 2 O 2 and S 2 O 8 2− activation was found. The highest BPA degradation rates were achieved at acidic conditions (pH 3) with both H 2 O 2 and S 2 O 8 2−, however persulfate showed a significant efficiency even at pH 6, interesting feature in the light of decreasing the wastewater treatment costs. By the addition of selective quenching agents, OH and SO 4 – were identified as the main reactive species involved in the BPA abatement. An important contribution of the S 2 O 8 2− photolysis on the overall BPA transformation was highlighted. The reuse of the catalyst was investigated and similar efficiency using H 2 O 2 and S 2 O 8 2− activation was observed until the third catalytic cycle. Experiments carried out using real wastewater samples, showed a good, even if less efficient compared to pure water, BPA removal. [ABSTRACT FROM AUTHOR]