AWWA ACE61650

A process for the adsorption of contaminants from water using silica aerogel/granular activated carbon (GAC) composites has been developed by Lawrence Livermore National Laboratory (LLNL). Like GAC, the aerogel has a very large surface area (approximately 1000 m2/g), but it has the added advantage of being hydrophobic with a low density. Unlike GAC, the composite can remove both volatile organic compounds (VOCs) and metals. Previous work at LLNL has investigated uranium removal by a phosphorous enriched hydrophobic aerogel/GAC composite. Producing a P-enriched aerogel-GAC composite improved uranium removal above the GAC without the composite. Varying the type and amount of phosphorous (phosphonate, 1% or 17% H₃PO₄) affected uranium removal, based upon analysis of isotherm data. Additionally, adsorbency was confirmed via column tests and a field demonstration. This paper briefly discusses this uranium-related work to demonstrate the potential for aerogel-GAC composite materials to remove oxo-anions. Includes table, figures.