Photoreactor-ultrafiltration hybrid system for oily bilge water photooxidation and separation from oil tanker

A novel design of hybrid system consisting of photoreactor (PR) combined with ultrafiltration (UF) membrane was investigated for oily bilge water degradation and separation from oil tanker. Initially, the bilge organic compounds were photooxidized using ultraviolet type A (UVA) light irradiation on 100, 200 and 300ppm of TiO2. Further TiO2 and oxidized oily bilge water was filtered using hollow fiber membrane separator, which was prepared by polyvinylidene fluoride (PVDF) and halloysite nanotubes. The hollow fiber membranes were characterized by ATR-IR spectrum, thermal gravimetric analysis (TGA), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and X-ray photoelectron spectroscope (XPS). Individual hydrocarbon of oily bilge water was identified by using gas chromatography–mass spectrometry (GC–MS) analysis. According to the GC–MS analysis, over 90% decomposition of oil in bilge water has occurred by 200 and 300ppm of TiO2 suspension. On the other hand, pH meter showed that, decomposed oily bilge water was more acidic, which increased to pH7 after UF system process. Moreover, over 99% of degraded oil in bilge water was filtered by this promising hybrid system.