Changes in the physico-chemical characteristics of a protein solution in the presence of magnetic field and the consequences on the ultrafiltration performance

The use of magnetic field in protein solution (bovine serum albumin/BSA) was proposed as a strategy to improve the ultrafiltration (UF) performance. Permeation tests of BSA (2.5 g L−1 and pH 6.5) through a 50 kDa hydrophilic polyethersulfone (PES) membrane were carried out in a tangential flow module. The magnetic induction effect (MI) on the feed solutions was studied by submitting the feed to the magnetic field (magnetic flux density 0.7 T and 1.4 T) for 0.5 h, 2 h and 12 h before permeation runs. Positive effects were observed in the permeate flux with flux increase up to 195% compared to control. Also, a reduction in the fouling resistance from 59% (control) to 18% and 16% using 2 h of magnetic induction under 0.7 and 1.4 T, respectively, was noted. This behavior can be attributed to changes in structure and zeta potential of the BSA solution after magnetic field exposition, then increasing the repulsion between the membrane surface and the protein molecules.