Nitrate removal of drinking water by means of catalytically active membranes

The reduction of nitrate to nitrogen in aqueous solutions by means of catal ytically active membranes has been investigated. A heterogeneous catalyst ( Pd/Cu) has been incorporated in a microporous polyetherimide membrane. Afte r saturation with hydrogen nitrate containing water was filtered through th ese membranes. The nitrate reduction was studied as a function of pH, volum e flow and temperature. It could be demonstrated that the catalyst remained active in the polymer matrix. The calculated activation energy for nitrate reduction is indicating that the reaction is dominated by mass transfer an d diffusion. (C) 1998 Elsevier Science B.V. All rights reserved.