The potential of hybrid electrocoagulation-membrane separation processes for performance enhancement and membrane fouling mitigation: A review

Membrane separation processes have gained more attention with time for their rapid improvement in different aspects such as configurations, the introduction of innovative materials into the engineering of modules, and the development of membrane materials and manufacturing techniques. However, on the other hand, these techniques suffer from an extremely critical problem, which is membrane fouling. This is due to the tiny size of membrane pores, in addition to the pretreatment methods before membrane separation that can be a part of the problem. A simple and cost-effective technique like electrocoagulation (EC) can offer a solution; it has an advantageous capability to remove a wide range of pollutants efficiently and rapidly without using any additives that can cause secondary pollution. In this respect, the present review provides a thorough investigation of the role of EC as a pretreatment step preceding different membrane separation processes such as microfiltration, ultrafiltration, nanofiltration, reverse osmosis, membrane bioreactors, and membrane distillation, in addition to the effect of the hybrid process on the percentage of pollutants removal and the mitigation of membrane fouling as well. Most of the recent literature supports using the efficient pretreatment method of EC instead of the ordinary multiple pretreatment sequences.