a b s t r a c tOne of the main problems faced by the oil industry is related to the amount of produced water generated during the oil extraction process, and therefore, the disposal of this effluent, which must undergo treatment processes to meet the specifications for disposal or reinjection into oil wells. Thus, this research aimed to study the oil-water separation through the electroflotation process, using a simulated wastewater prepared by mixing water, lubricating oil and NaCl. To this end, the effect of operational variables: effluent input rate, current density and NaCl concentration were studied in a pilot system. The performance of the process was determined by the removal of oil and grease (OG) content in the treated effluent. According to the results, the electroflotation process showed a good separation efficiency, presenting an OG removal of 94.96% for the input rate of the effluent from 62 m 3 m -2 d -1 , current density of 80 A m 2 and the NaCl concentration of 7,900 mg L -1 . The final concentration of OG was 13.15 mg L -1 . These results encourage the applicability of electroflotation as a treatment process for the petrochemical industry.

ANOVA: analysis of variance; CCRD: Central Composite Rotational Delineation; DOC: dissolved organic carbon; DSA: dimensionally stable anodes; LAPOA: Laboratory of Water Potabilization; OG: oil and grease; OPER: operating parameters of the electrochemical reactor; TDS: total dissolved solids; UFSC: Federal University of Santa Catarina.