Surface Modification Of Membranes For Antibiofouling

Biofouling, i.e. the undesirable formation of biofilm, has been called the Achilles heel of membrane processes for water treatment. It is often so severe that acceptable performance cannot be maintained and higher operating pressure, chemical cleaning, and even membrane replacement are unavoidable. Therefore, it is quite necessary to explore effective methods to reduce or suppress biofouling for membranes. In this chapter, the formation process of membrane biofouling is briefly introduced at first, including a cascade of events of bacteria: adhesion, production of extracellular polymeric substances, growth and proliferation. Among them, the attachment of bacteria to the membrane surface is a critical step. There are many influencing factors, where one of the most important is the surface properties of the membrane materials. Hence, the effects of membrane surface properties (hydrophobicity, surface charge and morphology) on the biofouling are also discussed. Thereafter, we focus on the surface modification of membranes for antibiofouling. Herein, two surface modification strategies for antibiofouling: surface hydrophilization and surface immobilization of antibacterial agents are reviewed.