M. Pouliot et al., EFFECTS OF PH AND IONIC ENVIRONMENT ON THE PERMEABILITY AND REJECTIVEPROPERTIES OF AN ALUMINA MICROFILTRATION MEMBRANE FOR WHEY PROTEINS, Journal of membrane science, 95(2), 1994, pp. 125-134
An alumina microfiltration membrane of 0.2 mu m pore diameter was used
for the concentration of whey proteins in solutions of NaCl (0.08 M)
and whey UF permeate at different pH, in order to study the effect of
the physicochemical environment on the hydraulic resistance and the re
jection of whey proteins during microfiltration. Similar filtration be
haviour was found between the systems in 0.08 M NaCl and whey UF perme
ate. Lowering the pH of the protein solutions caused an important incr
ease in total hydraulic resistance particularly for the reversible and
irreversible partial hydraulic resistances. The rejection of proteins
(greater than or equal to 0.40) was only slightly affected by differe
nces in solvents and pH. It is believed that protein deposition in the
pores under the influence of shear and electric charges of both membr
ane and proteins is responsible for the hydraulic resistances measured
.