Elaboration and characterization of new conductive porous graphite membranes for electrochemical advanced oxidation processes

• Simple and robust preparation route to synthesize low cost membranes.
• Well-controlled porosity and electronic conductivity of graphite based membranes.
• Graphitization degree closely related to the carbonization temperature.
• Membranes with good ability to mineralize organic pollutants by Electro-Fenton process.

Three different graphite powders with different particles sizes were tested to synthesize tubular monochannel carbon supports for micro and ultrafiltration membranes using a new process. Carbon graphite powders and organic additives were mixed with an ethanolic solution of Resol® type phenolic resin. The extruded tubes were firstly consolidated by curing the resin at 150 °C then carbonized under nitrogen stream (1 mL min−1) for graphitization and pores opening.Supports with optimal properties were obtained using a mixture of Resol® resin and a 44 µm particle size graphite powder, carbonized at 1000 °C. They showed a porosity value of 37%, an average pore size diameter of 3 µm, high mechanical and chemical resistances and an average conductivity of 190 Ω−1 cm−1.The Raman spectroscopy results show that graphitization degree of the material is closely related to the carbonization temperature, which explains the increase of conductivity with temperature.Acid Orange 7 (AO7), a common dye, was finally used as a model molecule to demonstrate the ability of the graphitic membranes to mineralize organic pollutants by electro-Fenton process. Spectrophotometric measurements were conducted on the treated solutions as a function of chemical and electrochemical conditions to determine the degradation kinetic of AO7. Decolorization rate was also measured as a function of time.