Ultra-hydrophobic aluminum foam development for potential application in continuous water-oil separation processes

Owing to their applicability as a selective barrier, porous materials with modified surfaces have been presented as alternatives for addressing oil spills in water. For this application, surface treatment seeks both maximization of surface area and formation of a low-energy layer. To achieve an effective selective barrier that is useful in the separation of oil-water mixtures, with future application in oil spill cleanup, this work presents aluminum foams treated with sodium hydroxide and immersed in dodecanoic acid to achieve pickling and reduction of surface energy, respectively. Treatment efficiency was evaluated using the Brunauer–Emmett–Teller method and contact angle measurements. Results were consistent with other hydrophobic materials. Pore sizes of 425 µm, 850 µm, and 1200 µm were used to evaluate separation of water and oil mixtures under static and dynamic conditions. Oil recovery efficiencies for all pore sizes were greater than 98%.