Promotion of conductive carbon black loaded CuFe2O4 on the oxidative degradation of phenol by persulfate

The development of cheap and efficient catalysts for persulfate activation in advanced oxida-tion processes based on persulfate is important and promising in the wastewater treatment field. Herein, conductive carbon black loaded CuFe2O4 (CCB-CuFe2O4) had been prepared via a sol-gel method and was used as a catalyst to activate persulfate for the removal of phenol in water. The CCB-CuFe2O4 was characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, Brunauer-Emmett-Teller, and Raman spectroscopy, which confirmed that CuFe2O4 nucleated on the defect of CCB. The performance of the activation on persulfate was studied by determining the con-centration of phenol and chemical oxygen demand of the water. The activity of the catalyst is the highest when the content of CuFe2O4 in the catalyst is 10%. The removal rate of 100 mg/L phenol reached 100% in 30 min under the optimized operation condition, which was 2.0 g/L CCB-CuFe2O4, 2.0 mmol/L persulfate (PS) and pH = 11. The factors of effect on the catalysis performance were dis-cussed. CCB-CuFe2O4 can be used in the pH range of 3 similar to 11 and the presence of HCO3- can promote phenol degradation rate. The use of CCB-CuFe2O4 catalyst obviously reduced the dose of PS in the process of phenol oxidation degradation. Furtherly, quenching experiments verified that the most important reactive species in the CCB-CuFe2O4/PS/phenol system is singlet oxygen (O-1(2)).