RESUMEN
An electrocoagulation technique using a 3.5â¯L reactor, with aluminum electrodes in a monopolar arrangement with polarity switch at each 10â¯s was used to separate oil from synthetic oily water similar in oil concentration to produced water from offshore platforms. Up to 98% of oil removal was achieved after 20â¯min of processing. Processing time dependence of the oil removal and pH was measured and successfully adjusted to exponential models, indicating a pseudo first order behavior. Statistical analysis was used to prove that electrical conductivity and total solids depend significantly on the concentration of electrolyte (NaCl) in the medium. Oil removal depends mostly on the distance between the electrodes but is proportional to electrolyte concentration when initial pH is 8. Electrocoagulation with polarity switch maximizes the lifetime of the electrodes. The process reduced oil concentration to a value below that stipulated by law, proving it can be an efficient technology to minimize the offshore drilling impact in the environment.