The possibility of using an ultrafiltration technique to improve the q
uality of the commercial, technical proteolytic enzyme preparation, Pr
oteopol BP-S was studied Membranes synthesized from polyacrylonitrile
in the shape of tubes were selected and the optimum or limiting values
of the operational parameters of the process, namely transmembrane pr
essure, flow velocity of the solution tangentially to the membrane and
temperature, were determined.