Fabrication of an Oil Spill Collector Package by Using Polyurethane Foam Wrapped with Superhydrophobic ZnO Microrods/Carbon Cloth

Abstract

A new package, including polyurethane foam wrapped with superhydrophobic ZnO microrods/carbon cloth with long-life elasticity, was fabricated and was utilized for oil spill clean-up. First, the carbon cloth (CC) was coated with ZnO microrods, which were modified with stearic acid (SA) to obtain superhydrophobic and superoleophilic properties. The coating process was conducted in mild conditions, involving the hydrothermal growth of ZnO microrods on the surface of the carbon cloth. The obtained hydrophobic sample was modified to a superhydrophobic one by adsorption of stearic acid (SA) on its surface. The prepared sample (CC/ZnO/SA) was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectra (FTIR), attenuated total reflectance Fourier-transform infrared spectroscopy (ATR-FTIR), and contact angle measurements. The prepared sample shows a water contact angle (WCA) of 160°. A piece of polyurethane foam was wrapped with the prepared superhydrophobic CC/ZnO/SA making an oil collecting package, which can float on the water surface and absorb various oils from the water surface in both static and turbulent conditions very quickly. The prepared package exhibits excellent mechanical robustness and can be used several times for oil/water separation without capacity decrease. The kinetics of oil spill absorption by the prepared package were studied, too.

Keywords: ZnO microrods; carbon cloth; oil/water separation; superhydrophobicity; superoleophilicity.