One-step dip-coating method for preparation of ceramic nanofiber membrane with high permeability and low cost

Abstract

Ceramic nanofiber membrane (CNM) based on attapulgite (APT) without any intermediate layer neither any cracks was fabricated by a one-step dip-coating method. The effects of sintering temperature and dip-coating time on the physicochemical properties and performances of prepared CNMs were investigated. The increase of the sintering temperature up to 700 °C reduced the bending strength, porosity and chemical stability of APT-based CNMs. Meanwhile, with the dip-coating time increased, the membrane thickness increased thereafter reduced. The APT-based CNM fabricated at a sintering temperature of 600 °C and with a dip-coating time of 15 s had an average pore size of 20.4 nm, high porosity (above 60 %), good permeability of 118 L/m2 h bar and a rejection of 96.6 % polymers with a molecule weight of 600 kDa. All these properties clearly suggest the practicability of the one-step dip-coating method to prepare ceramic nanofiber membranes.