Application of Electrocoagulation in Treatment of Spent Caustic from Olefin Plants

Abstract

In this research the electrocoagulation method was implemented in order to study the treatment of the spent caustic effluent from an olefin plant. To optimize the process parameters, Taguchi method was used, and the optimal conditions were found for pH of 6, current density of 35 mA/cm2, and treatment time at 40 minutes. The experimental results show that the final efficiency in case of reducing the amount of COD is around 89% under optimum operating conditions and pH has the most significant impact on the process with contribution factor of 79.10%. According to results of XRD and XRF analysis, the sludge behavior is very similar to that of sodium sulfate that is important for its value chain. The study results showed that the electrocoagulation method could be used a complimentary facility to reduce the amount of COD of Spent Caustic from an Olefin Plant.