Jointly published by React.Kinet.Catal.Lett. Akadémiai Kiadó, Budapest Vol. 77, No. 2, 263-266 and Kluwer Academic Publishers, Dordrecht (2002) 0133-1736/2002/US$ 12.00. © Akadémiai Kiadó, Budapest. All rights reserved. RKCL4065 Pt-Cu/ZSM-5 FOR REMOVAL OF NITRATES FROM DRINKING WATER Carolina Pfaff a , Luis Melo a and Paulino Betancourt b a Departamento de Química Aplicada, Facultad de Ingeniería, Universidad Central de Venezuela, Caracas, Venezuela b Centro de Catálisis, Petróleo y Petroquímica, Facultad de Ciencias, AP 47102. Los Chaguaramos, Caracas, Venezuela. Tel.: 58-212-6051649. E-mail: pbetanco@strix.ciens.ucv.ve Received January 28, 2002 In revised form June 4, 2002 Accepted June 17, 2002 Abstract Removal of nitrates from drinking water by catalytic hydrogenation over ZSM-5 supported Pt-Cu catalysts was studied. Bimetallics Pt-Cu were prepared by ion exchange of copper on a parent monometallic platinum catalyst. Monometallic platinum catalysts are inactive for nitrate reduction, while Pt-Cu bimetallic catalysts are active for nitrate removal. In the bimetallic catalyst, the role of copper is probably to reduce nitrate according to a redox reaction. The addition of copper to Pt catalysts decreases the production of ammonium ions Keywords: Nitrates, reduction, Pt-Cu / ZSM-5 catalysts INTRODUCTION Nitrate is a commonly found contaminant in ground water, due to agricultural, industrial and domestic practice. Excessive nitrate in drinking water can cause methemoglobinemia in humans; the current drinking water standard for nitrate (NO 3 - - N) is 10 mg L -1 . Therefore, there is a considerable public interest and regulatory pressure to clean-up nitrate-contaminated aquifers. In order to reduce the content of these pollutants in water, several physico-chemical and biological processes have been proposed, such as ion exchange, electrodialysis, reverse osmosis or microbiological treatment [1,2].