Hydrocarbon degradation and separation of bilge water via a novel TiO2-HNTs/PVDF-based photocatalytic membrane reactor (PMR)

Abstract

This paper focuses on the potential of a novel flat sheet nanocomposite titanium dioxide (TiO₂)-halloysite nanotubes (HNTs)/polyvinylidene fluoride (PVDF) membrane as a photocatalytic separator in the photocatalytic membrane reactor (PMR). The photocatalytic nanocomposite membrane acted the roles of both degradation and separation for bilge water. Both TiO₂-HNTs photocatalyst and photocatalytic nanocomposite membranes were characterized by thermogravimetric analysis (TGA), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and field emission scanning electron microscopy (FESEM) combined energy dispersive X-ray spectroscopy (EDX). The hydrocarbon degradation and removal efficiency of the PMR was evaluated by gas chromatography mass spectroscopy (GC-MS). It was found that 99.9% of hydrocarbons were removed by the PMR within 8 h, which is likely due to uniform distribution and high effectiveness of the TiO₂-HNTs photocatalyst in the PVDF polymer matrix. The TiO₂ leaching from the nanocomposite membrane during the membrane permeation was analyzed using flame atomic adsorption spectrophotometer (AAS), which recorded 1.0 ppb of TiO₂ leaching in the permeate tank.