An unsteady state mass transfer model has been developed taking into accoun
t the effect of reversible pore plugging by the diffusing solute molecules.
The osmotic pressure model has been used to predict the membrane surface c
oncentration. The rate of available fractional area of the membrane that is
blocked at any time due to pore plugging phenomenon has been assumed to be
the function of dimensionless membrane surface concentration prevailing at
that time. Experimental data generated in this study using cellulose aceta
te membrane of 5000 MWCO and polyethylene glycol (PEG)-6000 as solute in un
stirred batch configuration has been used to find the appropriate nature of
the above-mentioned function. Once the functional dependency between the r
ate of fractional area blocked and dimensionless membrane surface concentra
tion has been found, it can be used to simulate flux and rejection behaviou
r during unstirred batch ultrafiltration (UF). The predicted results show v
ery good agreement with the experimental data and the average deviations fo
r all the cases are found to be well within +/-10%. (C) 2000 Elsevier Scien
ce B.V. All rights reserved.