Wide applications of engineered nanoparticles (eNPs) have potential environmental and health risks. This paper focuses on the removal of polystyrene nanoparticles by hollow fiber membranes of three different pore sizes. The effects of the running time, the inflow pressure, the flow rate, the concentration and the particle to pore diameter ratio are investigated. The results show that it is feasible to remove the eNPs by the UF/MF membrane. The retention rate is stable and there are no obvious differences after the filtration of the UF membrane for 10 minutes. The retention rate increases when the inflow pressure increases from 25 kPa to 125 kPa, the concentration increases from 25 to 100 mg·L^-1, but no obvious variation when the flow rate increases from 0.12 to 0.59 m·s^-1. The retention rate is influenced when the particle to pore diameter ratio is less than 1. The retention rate at 10 min is very close to the value predicted by the Nakao model.

ultrafiltration membrane  /  microfiltration membrane  /  polystyrene nanoparticles  /  retention rate