A sacrificial-interlayer technique for single-step coating preparation of highly permeable alumina membrane

A single-step coating preparation of highly permeable alumina microfiltration membrane on as-prepared alumina supports has been achieved by using a sacrificial-interlayer technique. The sacrificial interlayer was derived from polyvinyl alcohol (PVA)-boric acid complexation and crosslinking. The supports covered with the sacrificial interlayer was dipped into the membrane forming slurry. The sandwiched structures including the green ceramic membrane, the sacrificial interlayer and the support were obtained. The membrane sintered at 1200 degrees C for 2 h has an average pore size of 0.24 gm and a water permeance of 1410 L m(-2) h(-1) bar(-1) which is significantly higher than that of the membranes prepared with other methods.