Interactions of Natural Organics with Colloids

Inorganic colloids in surface waters may be the oxy/hydroxides of Mn, Fe, Al and Si, as well as carbonates and clays, with a size range from a few nanometres up to millimetres (Thurman (1985), Morel and Hering (1993)). Such colloids have been extensively characterised and modelled (Ledin et al (1995), Wilkinson et al (1995), Filella et al (1993), Leppard et al (1990), Filella and Buffle (1993), Ferret et al (1994), Newman et al (1994)). Colloids in a natural environment often have a negative surface charge and occur in large organic matrices. Solution chemistr) and surface properties control the colloidal stability of these natural particles. 

The interactions between colloids, organics, and multivalent ions surest the importance of these phenomena in the membrane filtration behaviour of natural waters containing colloids and organics. 

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