Adsorption and fouling characterization of Klebsiella oxytoca to microfiltration membranes

The Klebsiella oxytoca  , a dominating strain in the membrane biofouling layer of treating wastewater membrane bioreactor (MBR), was taken as a model in this manuscript. Its surface properties and interfacial energy were first explored. Then its adsorption and fouling properties on polyvinylidenefluoride (PVDF) and polypropylene (PP) membranes were characterized, respectively. With the higher total surface tension (rTOT)(rTOT) and van der waals force (rLW)(rLW), the K. oxytoca cell and the PVDF membrane were more hydrophilic than the PP membrane. Both membranes and K. oxytoca were proved to be typically strong electron donors. The negative total interfacial energy occurred in both K. oxytoca-membrane systems. K. oxytoca showed stronger attraction to PP membrane than to PVDF membrane within a short range. More K. oxytoca tended to be adsorbed on PP membrane than on PVDF membrane. The permeation flux decreased with increasing the pressure, and K. oxytoca showed a greater fouling potential to PP membrane.