Degradation of Polycyclic Aromatic Hydrocarbons (PAHs) in Produced Water

Produced water represents the largest volume of waste stream in oil and gas exploration and production operation. Presence of Polycyclic Aromatic Hydrocarbons (PAHs) in produced water has created tremendous effects on the environment and human health due to its toxicity, mutagenic and carcinogenic effects. In this study, the produced water sample was collected from a local petroleum refinery. This study determines the suitability of Advanced Oxidation Process using Fenton’s reagent specifically for the treatment of PAHs-contaminated water. The samples were acidified to selected pH value, ranges from 2-5 and FeSO4 and H2O2 were added following 1:4, 1:3, 1:2 and 1:1 ratio. The pH of reaction mixtures were raised to 10~12 to decompose H2O2 and to stop oxidation of organic matter prior to COD and TOC measurement. Gas Chromatography-Mass Spectrometer (GC-MS) was used for determination of PAHs after an enrichment step of Liquid-Liquid Extraction (LLE) as re-concentration technique was implemented. The maximum COD and TOC removal achieved in the designed Fenton system was 77.0% and 83.9% respectively, under operating condition of pH 3, 1.5ml H2O2, 0.5g Fe2+ and 180 minutes reaction time. Total PAHs removal was 72.5%, using similar conditions established for COD and TOC removal.