AWWA JAW56658

Organically modified clays have proved to be an effective and economical medium for removing small amounts of oils from water. Organoclays are also a good prepolisher for activated carbon, membranes, reverse osmosis units, and ion exchange resins - media that tend to become blinded by oil droplets that coat the openings. Although organoclays have been used successfully for many years, little data existed about the optimum chemical conditions for their use or the best organoclay for a particular application. Tests conducted on some 50 oils of all classifications found that organoclays are superior to activated carbon for oil removal and that cationic organoclays are more effective for removal of the more-polar crude oils. Because water is an increasingly rare commodity, more priority and attention have focused on conserving and recycling water. Organoclays help achieve that goal by removing oil and grease at less cost than carbon and with minimal maintenance. Includes 6 references, table, figures.