Development and applications of very high ̄ux micro®ltration membranes

Inorganic micro®ltration membranes with a pore size down to 0.1 mm have been made using laser interference lithography and silicon micro machining technology. The membranes have an extremely small ̄ow resistance due to a thickness smaller than the pore size, a high porosity and a very narrow pore size distribution. They are relatively insensible to fouling, because they have a smooth surface, short pore channels and because they can be operated in cross ̄ow con®guration at very low transmembrane pressures. Experiments with yeast cell ®ltration of beer show a minimal fouling tendency and a ̄ux that is about 40 times higher than in conventional diatomaceous earth ®ltration. The uniform pore distribution makes the membranes suitable for many other applications like critical cell to cell separation, particle analysis systems, absolute ®ltrations and model experiments. # 1998 Elsevier Science B.V. All rights reserved.