The study examined modified Fenton (FeGAC/H2O2) pretreatment of the antibiotics amoxicillin and cloxacillin in aqueous solution for biological treatment. The treatment was optimized by the response surface methodology (RSM). The optimum operating conditions at pH3 were H2O2/COD molar ratio 2.0, FeGAC dose 3.5 g/L and reaction time 90 min for 87.53% removal of COD, 78.01% removal of TOC, and 98.24% removal of NH3-N. Biodegradability (BOD5/COD ratio) improved from zero to 0.36, indicating the effluent was amenable to biological treatment. Meanwhile, FTIR spectra indicated degradation of the antibiotics. Compared with Fenton or photo-Fenton, modified Fenton (FeGAC/H2O2) was more effective in the pre-treatment of the antibiotics amoxicillin and cloxacillin in aqueous solution for biological treatment.
This study examined the combined UV/Fenton and sequencing batch biological reactor (SBR) treatment of a semi-aerobic landfill leachate. Fenton pretreatment of the leachate was optimized by the response surface methodology (RSM). UV/Fenton pretreatment of the leachate was performed under the optimum operating conditions of the Fenton pretreatment (H2O2/COD molar ratio 2.25, H2O2/Fe2+ molar ratio 10.0 and reaction/irradiation time 1.5 h). The characteristics of the UV/Fenton pretreated leachate were: COD 390 mg/L, sCOD 330 mg/L, BOD5 136 mg/L, BOD5/COD ratio 0.35, NH3-N 112 mg/L, TKN 157 mg/L, NO3--N 6.8 mg/L and colour 99 Pt-Co Unit. SBR treatment of the UV/Fenton pretreated leachate resulted in sCOD, BOD5 and NH3-N removal of 78%, 81% and 88%, respectively. The final effluent characteristics were: COD 92 mg/L, sCOD 71 mg/L, BOD5 26 mg/L, NH3-N 7 mg/L, NO3--N 27 mg/L, TKN 13 mg/L and TSS 38 mg/L. The effluent met the Malaysian discharge standard (B) – COD 100 mg/L, BOD5 50 mg/L and TSS 100 mg/L. Combined UV/Fenton and SBR is an effective treatment for mature leachate from semi-aerobic landfill.