Organically modified clays (Organoclays) have been used over the past 20 years to remove oil, grease, PCB, PNA, phenols, BTEX and other compounds of low solubility, from water. They remove up to 60% of their weight in oil. The removal action takes place by partition, which results in the compounds being fixated by the quaternary amine chains which are attached to the bentonite granules. An Organoclay consist of a quaternary amine chain being ion exchanged onto bentonite, which results in a non-ionic surfactant with a solid base.
It has been found that if the amount of quaternary amine is varied, the organoclay can be converted into an ion exchange resin and used to remove polar compounds such as nitrates, perchlorate, arsenate, etc.
This article reports on the results of column tests conducted in a laboratory.
