Fenton’s Reagent for the Treatment of Pharmaceutical Industry Wastewater

Pharmaceutical industry often generates highly toxic wastewater and sludge depending upon the used manufacturing process and season. The high BOD to COD ratio of this particular wastewater makes biological treatment difficult. Hence chemical treatment proves to be a useful option. Fenton’s reagent is used in the treatment of pharmaceutical industry wastewater in this study. The ferrous and hydrogen peroxide were used in the molar ratio of 1:1, 1:2 and 1:3. Ferrous was added in the form of ferrous sulphate. A reaction time of one hour was provided. A magnetic stirrer was used for mixing the Fenton’s reagent and the wastewater sample. Different doses of hydrogen peroxide and ferrous sulphate was added as per the ratio decided. 82% reduction of COD was observed at 3267 mg/L of ferrous sulphate and 800 mg/L of hydrogen peroxide for 1:1 ratio. For a ratio of 1:2 an efficiency of 85% COD reduction was observed at doses of 3675 mg/L of ferrous sulphate and 900 mg/L of hydrogen peroxide. For ratio of 1:3 the maximum reduction of COD was observed in doses of 2450 mg/L of ferrous sulphate and 900 mg/L of hydrogen peroxide. Based on these dosages the removal of other parameters of wastewater like phenol, heavy metals, total phosphates, total dissolved solids and ammonia nitrogen were analyzed. The ferrous sludge generated has good settling characteristics and has potential for recovery of iron.