Application of Thin-film Nanocomposite membrane in Treatment of Hydrocarbon Produced Water from Brown Field, Niger Delta

Hydrocarbon extraction from underground reservoirs is often associated by water or salt-water, known as produced water. As the reservoir matures, the amount of water increases and often exceeds the relative hydrocarbons before the reservoir is depleted, especially when secondary or tertiary production processes are used to enhance production. Membrane technology in literature have been applied as water treatment technique and it has been associated to with fouling; but in this study, inorganic fillers such as titanium dioxide (TiO2) have been added to improve its performance due to the limitation of conventional membranes. This study examines the application of permeable thin film TiO2 nanocomposite membrane in the treatment of produced wastewater from a hydrocarbon-brown field. TiO2 is the most common material in our daily life and its use in this study is due to the high degree of commercialization and excellent hydrophilic and photocatalytic properties which are of interest in environmental purification application. In this paper, cellulose acetate membrane was synthesized and further doped with TiO2 nanoparticles of different weight-percent (10, 20, and 30 wt %). The synthesized TiO2 nanoparticles were examined using Fourier Transform Infrared Spectroscopy, while the morphology of the synthesized membrane was analyzed using scanning electron microscopy. The results obtained from the experiments at constant pressure, shows that adding TiO2 nanoparticles to the cellulose acetate membrane structure enhanced the permeability and pore size of the membranes. The free surface energy of the nanocomposite membranes ranged from 58 +/- 0.9 to 73 +/- 0.9 mJ/m2, while that of the cellulose acetate membrane was about 73 +/- 0.9 mJ/m2. The pure water flux ranged from 18 L/m2h for the cellulose acetate membrane to 35 L/m2h for the TiO2 nanocomposite membrane. The trend shows that at constant pressure, permeate flux through the nanocomposite membrane will decrease with time. For the percentage retention analysis, adsorption is responsible for the higher retention, however, we found that retention decreased with increasing membrane saturation over time.