Pingli Li

Preparation and Evaluation of iPP/GO Microfiltration Membrane with Enhanced Antifouling Property

Isotactic polypropylene(iPP) and graphene oxide(GO), dispersed in dibutyl phthalate(DBP) and dioctyl phthalate(DOP), were blended to prepare organic-inorganic-blended microfiltration membranes using thermally induced phase separation(TIPS). These membranes were characterized by scanning electron microscopy(SEM), Fourier transform infrared spectroscopy(FTIR), contact angle measurements, mechanical properties, permeation tests, and porosity measurements. The morphology studied by SEM shows larger pores of the GO-blended membranes when compared to those of unmodified iPP membranes. Composite iPP/GO membranes achieve better performance in terms of water fluxes and pure water fluxes recovery ratio due to the hydrophilic nature of GO when compared with the pure iPP membranes. The addition of GO increases the permeability and the tensile strength by 352.98% and 123%, respectively, and also decreases the contact angle from 125° to 52.33°. We concluded that the composite membrane with 0.3% GO has the best antifouling ability of the membranes tested because it has the highest values of mean pore radius, porosity, and water flux observed in this study.

Removal of copper sulfate from aqueous solution by air-gap membrane distillation process

The potential use of air-gap membrane distillation (AGMD) process for the removal of copper sulfate (CuSO4) from aqueous solution was examined. A series of experiments were conducted to investigate the effects of both operation parameters and module parameters, including hot feed temperature(T3), coolant temperature (T1), feed flow rate (F), feed salt concentration (cf), vacuum pressure (P), the rate of hollow fiber membranes and heat-exchange hollow fibers (Nm/Nd) and the length of the modules (L) on permeate water flux (J), gained output ratio (GOR), water productivity (PV), and salt rejection rate (R) in AGMD process. It was found that the performance of AGMD process could be enhanced, but permeate water quality was deteriorated by adding vacuum pressure. Moreover, J declined, but PV and GOR increased as L increased. With the increment of Nm/Nd, J decreased when operation parameters keep constant, PV and GOR showed different variation trends with different T1 values due to the insufficient cold energy. The highest CuSO4 rejection rate exceeded 99.95%, so AGMD process has potential for CuSO4 separation from aqueous solution.