A method for the reductive electrochemically catalytic elimination of nitrate from concentrated solutions

摘要

Nitrates are removed from concentrated aqueous salt solutions using a combination of electrochemical and catalytic processes. Process for removing nitrates from concentrated aqueous solutions comprises using a membrane electrolysis cell (1) having an anode chamber (8) and a cathode chamber (5) divided by a cation exchange membrane (4). A cathode material is used whose over voltage is lower for electrochemical nitrate reduction than for electrochemical nitrite reduction. The electrochemical evolution of hydrogen and the cathode potential are chosen so that the nitrate is reduced at the cathode (2) to nitrite and the nitrite is converted to molecular nitrogen by introducing hydrogen as reductant to a catalyst.