ABSTRACT
Some membrane processes are particularly well suited to
the separation and purification of biological molecules[1]
since they operate at relatively low temperatures and pres-
sures and involve no phase changes or chemical additives.
Thus, these processes cause minimal denaturation, deacti-
vation, and/or degradation of highly labile biological cells
or macromolecules. Microfiltration (MF) is one of these
processes, and this explains the impressive development of
its industrial applications. MF is the largest industrial mar-
ket within the membrane field,[2,3] responsible for about
40% of total sales, both in Europe and in the United States.
The global market for MF membranes used in liquid
separations was estimated at $792 million in 2005,[4] rising
at an average annual growth rate (AAGR) of 9.4% during
the next 5 years, much more rapidly than the predicted
world GDP growth (3-4%), but not as rapidly as the
world market for some other membrane types, such as
reverse osmosis (10.3%).
