FLUX DECLINE BEHAVIOR IN DEAD-END MICROFILTRATION OF PROTEIN SOLUTIONS

Constant pressure microfiltration of solutions of the protein bovine serum albumin (BSA) has been studied in a batch filtration cell without stirring. Row resistance increased dramatically with time compared with the initial membrane resistance while most of the solutes passed through the membrane. The variation of the filtration flux rate with time during extended filtration periods could not be analysed by a unique blocking filtration law. The long-term decline in the filtration rate was accurately described by considering the variation of the value of the exponent i in the general characteristic form of the blocking filtration laws. It was found that the value of i continued to decrease with the progress of filtration. In addition, the effects on the filtration rate due to the solution pH, the filtration pressure, the fluid solute concentration, and the membrane type were described based on the general characteristic form of the blocking filtration laws.