It is known that a key limiting factor to the use of ultrafiltration membranes is that of membrane fouling, which has been a major cause of permeate flux reduction. In this work, the effects of several factors (operating time, protein concentration, temperature and pH, etc.) influencing permeate flux dur¡©ing ultrafiltration of gelatin, casein and bovine serum albumin using a hollow fiber membrane(M. W. 10,000 cut off) reactor have been examined. The permeate flux of gelatin solution was maintained almost constant during the operation up to 6 hours, but those of casein and albumin solutions were de¡©creased to 50% and 43% of initial value after an operation time of 60min. The permeate flux with in¡©creasing concentration and temperature of protein solutions increased, but the permeate flux showed a minimum value near the isoelectric point of proteins. The permeate fluxes of protein solution were en¡©hanced by a temperature increase and pH control. Also, it is proposed that fouling can be decreased by the pretreatment of insoluble proteins with enzymes.
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