New Process for Perchlorate Reduction in Drinking Water Treatment Units

Perchlorate contamination of ground waters and drinking water supplies is emerging as a major problem because it causes irreversible brain damage and other health effects, especially in the fetus and young children. Present perchlorate treatment is expensive and creates a secondary brine, with high levels of nitrate and perchlorate for its users to deal with. Our SBIR project is expected to provide a low cost solution with no secondary residuals for customers to deal with. Our new perchlorate reduction technology is based on a chemically impregnated granular activated carbon (GAC). The manufacturing process is designed to provide the maximized amount, position and species of active reagent in GAC to solve different clients percholrate problem(s). In addition to solving the perchlorate problem in drinking water treatment units (DWTU) at the point of use (POU) scale it ha applications in municipal and military installations applying GAC for pump-and-treat adsorption of trance organics in addition to perchlorate at 20,000-40,000 pound adsorbent used. The proposal presents novel concepts for the application of iron based chemistry for pollution control applications. Smart composite materials prepared and performance tests in this project offer a wide array of perchlorate and other simultaneous environmental problem solving applications. This PI has a proprietary laboratory capability called the Gravimetric Rapid Pore Distribution (GRPD) method, which provides information about the adsorption energy distribution of sites in heterogeneous adsorbents like GAC. The GRPD method provides valuable information to sorbent manufacturers and users not obtainable by any other present method. The chemical impregnant will be added at four concentrations and two distinctive forms, organic and inorganic. Perchlorate reduction will be evaluated with spiked drinking water using classical isotherms and mini-columns. Mini-columns provide the treatment performance: number of bed volumes and shape of the mass transfer zone. Our best new sorbent will be evaluated in a modified (sorbent replacement) DWTU from a major POU pour through pitcher manufacturer. We will apply our proprietary GRPD technology to validate the positional placement of our impregnants into GAC. Our goal is placement onto the transport pores and none of the GAC adsorption pores. Our new GAC product offers simultaneous trance organic removal (no loss of capacity in starting GAC) and inhibition of the GAC pH rise phenomenon, when it is first used in water application, in addition to perchlorate reduction. There are many targeted customers for this technology and many more will be available after the EPA and state set the MCL for drinking water and we fully understand the levels in our drinking water supplies.