Investigation Of The Separation Performance Of γ-Al₂O₃ Nanofiltration Membrane

Compared with organic nanofiltration membrane, inorganic nanofiltration membrane has many advantages, such as chemical stability, thermal stability, mechanical stability, and durability, although it is relatively expensive. There is a trend that organic membrane will be replaced by inorganic membrane. The application and investigation of it is a focus at home and abroad, But it is still in the stage of experimental investigation. The research was carried out with the orthogonal experimentation and single factor experimentation, in order to find out the effects of operating parameters (such as temperature of solution, operating pressure, velocity of cross-flow) and properties of feed solution (such as concentration and pH) on permeation flux and Mg²⁺ rejection of γ-Al₂O₃ tubular nanofiltration membrane under the conditions of acidic environment. And the results of both experiments were compared.It is shown from the experimental results that operating pressure and temperature were two very prominent factors influencing permeation flux under the conditions of the experiment. The effects of other factors, such as concentration, pH, and cross-flow velocity, were not so significant. Increasing operating pressure or temperature of experiment, permeation flux would increase obviously. The higher the concentration of feed solution was, the lower the permeation flux was. It was benefit for permeation flux to increase cross-flow rate, and the change of pH of feed solution...