Nitrate catalytic reduction in water: copper fixation effect in Pd-Cu/resin catalyst.

C. NEYERTZ; F. A. MARCHESINI; A. BOIX; E. MIRÓ; C. QUERINI

Salamanca- España

Congreso; European Catalysis Conference EuropaCAT IX; 2009

European federation of Catalysis Societies

The catalytic reduction with H2 is a promising alternative to eliminate nitrate contamination in water. One of the best catalysts for nitrate reduction is based on the Pd-Cu system. Few investigations were published studying resins as support. In this work, the properties of 2%Pd-0.5%Cu/resin prepared using different copper fixation procedures such as ion exchange method and controlled surface reaction, were investigated. The samples were tested in batch reactor of nitrate solution with H2 bubbling and constant pH. The fresh and used catalysts were characterized by TEM, EPMA, XRD and XPS. A higher activity was observed when the catalyst was prepared by the controlled surface reaction method. This is due to a higher palladium-copper interaction in the resin external surface achieved with this method. On one hand, there is an improvement due to the better interaction between the metals, and on the other hand, since the bimetallic particles are located on the external surface, better pH control can be achieved. XRD and TEM indicated that sinterization occurs during the reaction, leading to an increase in the average particle size.