Study on phosphorylated Zr-doped hybrid silicas/PSF composite membranes for treatment of wastewater containing oil

Polysulfone (PSF) membranes are broadly applied in the field of the treatment for wastewater containing oil owing to their good physicochemical stability, resistance to oxidation and chlorine. But they are easy to be contaminated by oil for its hydrophobic property, which limits their application in large scale. To enhance the capability of PSF membrane, such as hydrophilic property, anti-fouling ability and tensile strength, phosphorylated Zr-doped hybrid silica particles (SZP particles) were added to the porous matrix of PSF and a novel composite membrane (SZP/PSF) was prepared through a sol–gel process under optimum preparation conditions. The results of tensile strength and contact angle measurements show that the mechanical strength and hydrophilic property of composite membrane have been enhanced to a large extent respectively. SEM micrographs indicate that composite membrane with the asymmetry structure has both layers of compact layer and porous layer with SZP particles uniformly dispersed in PSF. The result shows that the oil concentration of 0.84 mg/L in permeation meets the standard for wastewater reuse (less than 10 mg/L). It can be concluded that the anti-fouling ability and hydrophilic property of composite membrane are significantly enhanced, and therefore, the novel composite membrane is desirable in the treatment of wastewater containing oil.