Separation of Uranium from Liquid Media

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U

Groundwater Remediation

Uranium is a natural element found in groundwater throughout the world and regulated in some countries. Uranium is usually present as the monovalent uranyl ionic complex (U3O8-) at very low levels in groundwater and thus the most cost effective treatment is to remove the uranium with a highly selective ion exchange resin and then dispose of the uranium-loaded resin.

Uranium can be removed from groundwater with AMBERLITE™ PWA17 Resin, a strong base anion resin that binds uranium very strongly. Because this resin is highly selective for uranium, the service length is frequently determined by the local disposal limitations with respect to radioactivity. Consult your local authorities to determine local regulations when using this approach to treat your water to remove uranium.

Mining

Worldwide, acid leaching with sulfuric acid is the most common method of extracting uranium from ores, with alkaline leaching being practiced primarily in the United States. However, based on available ores, alkaline leaching is becoming more common because of its lesser environmental impact. Current mining practices using lower concentration leaching solutions generate large volumes of pregnant leach solutions (PLS), which favors the use of ion exchange (IX) for the recovery-purification step because IX can more economically concentrate uranium from large volumes of PLS.

Many different engineered IX systems are used in uranium mining. The system used depends on local conditions and ore characteristics. Dow Water & Process solutions offers IX resins tailored to the type of leach and engineered system used. Please see the special page in the Markets section for product recommendations, depending on your application:

Uranium is 48th in abundance in the Earth's crust. It is very dense so it is used for ballistics and specialty applications. For its use in nuclear reactors, uranium must be extremely pure. Uranium is quite reactive, forming a wide range of intermetallic compounds.