It is well known that water contaminated with human waste is an important problem in a large part of the world; particularly in developing countries where substantial investments must be made in physical infrastructure so that water treatment plants could be used. In this regard, a feasible approach to face this problem is the development of on-site technologies using affordable and small devices that could be installed in every household. The aim of this project was therefore to design, build, and characterize a small Electro-Fenton reactor for human wastewater treatment.

The approach that was employed is based on the cathodic generation of H₂O₂ from oxygen reduction in activated carbon (AC) packed electrodes along with the combination of this species with H⁺ and Fe²⁺ ions provided by a cation exchange resin. In this way, a three-chamber reactor was built coupling an AC packed electrochemical system (middle compartment) with two additional compartments that contained a cation exchange resin that will change between source and collecting cation functions in cycles with a frequency 1/t₁. In this way, setting the flow rate in any given direction, one resin chamber provided protons and ionic iron as water flows trough it, taking these chemical species to the middle compartment where the Electro-Fenton process takes place. The second resin chamber collected the cations as they come out from the middle compartment and after t₁, when the resin-loaded chamber was loaded, the direction of the water flow and the potential in the electrode compartment was switched so that the process started over again.

From measurements of iron and proton desorption and adsorption along with electro-Fenton experiments, it was possible not only to obtain cycling-working conditions for the reactor under study but also to observe the successful coupling between the adsorption an cathode functions of the polarized AC packed in the central chamber of the reactor. Furthermore, using this small prototype to treat water contaminated with Helminth eggs (HE) of Ascaris lumbricoides (a human parasite that is highly resistant to the disinfection processes due to its robust external layers) it was possible to observe that the performance of the reported approach is promising since preliminary results showed a more efficient disinfection than that obtained using electrochemically generated hypochlorite.