Adsorptive partitioning of an organic compound onto polyelectrolyte-immobilized micelles on porous glass and sand.

Halting the spread of organic contaminants in subsurface aquifers is a critical environmental problem. We describe a novel "permeable reactive barrier" that results when organophile-solubilizing properties are conferred on siliceous materials by treating them with a cationic polymer and oppositely charged mixed surfactant micelles. Controlled pore glass, quartz sand, and sea sand were treated with poly(diallyldimethylammonium chloride) and with mixed micelles of Triton X-100 and sodium dodecyl sulfate, either sequentially or simultaneously, following different treatment procedures. A model organophilic compound, Orange OT, was adsorbed and retained under aqueous agitation on the siliceous treated surfaces but not on untreated surfaces or those treated with micelle only. The aspect of the treatment procedure producing the most significant effect on Orange OT solubilization was the ionic strength. The retention of Orange OT in a layer of polyelectrolyte-micelle-treated sand under flow, within a column of untreated sand, demonstrates the possibility of using similar processes as a permeable reactive barrier to trap organic pollutants.