Atomic-force microscopy investigations of filtration membranes

In this chapter we will discuss contributions which can be made to the study and characterization of filtration membrane surfaces using the technique of atomic-force microscopy (AFM), using specific examples. We will begin by giving an overview of the AFM technique itself, explaining the basic mode of operation, followed by a brief discussion of the contributions described in the literature. We will then concentrate on three examples of work which we have carried out recently using AFM to characterize various polymer membranes under different conditions. These examples are: the study of the effects of environment and imaging mode on the observations made of polymeric nanofiltration membranes using AFM; and the study of inorganic scaling on membranes used for seawater membrane distillation; the study of humic acid adhesion forces with novel polymer membranes under different conditions, including those simulating membrane bioreactor treatment of dye effluent.