Catalytic denitrification: direct and indirect removal of nitrates from potable water

A nitrate removal process that drastically reduces salt consumption and was te discharge has been developed on a bench scale. Nitrate is removed by chl oride ion exchange, and the strong-base anion resin is completely regenerat ed at mild reaction conditions (i.e., ambient temperature, atmospheric pres sure) in a closed circuit containing a single-flow fixed-bed reactor packed with a Pd-Cu/gamma -Al2O3 catalyst. The combined treatment system avoids d irect contact between the denitrification reactor and the water to be treat ed, and minimizes operational problems associated with each separate techni que. No dissolution of Pd and Cu metallic-phases was observed at the given operating conditions. (C) 2001 Elsevier Science B.V. All rights reserved.