Catalytic reduction of nitrate with Pd-InO.

This work presents a novel catalyst preparation method and the optimization of operation conditions for an effective NO conversion with a high selectivity and stability that guarantee water quality for human consumption. Catalytic reduction of NO and NO was carried out with Pd supported on InO under mild operation conditions (25 °C, 1 atm) with H and CO as reducing and acidifying agents, respectively. The catalyst was used in batch experiments showing the suppression of NO accumulation and low NH selectivity at acid pH. Long-term experiments were carried out with Pd on γ-AlO spheres covered with InO. This catalyst presented a high stability during more than 700 h. A concentration of NO below 50 mg/L was achieved, producing less than 0.5 mg/L of NH as reaction by-product by a strict limitation of the H fed and controlling several operating conditions.