| 摘要 |
<p>The invention relates to a method of producing an acidified aqueous solution containing alkali metal sulfate and chlorate comprising the steps of introducing and aqueous solution containing alkali metal sulfate and chlorate into an electrochemical cell and electrochemically increasing the acidity of said aqueous solution, wherein the current efficiency of the cell is maintained below 70%. The invention also relates to a method of producing chlorine dioxide comprising the steps: providing a reactor with an aqueous acidic reaction medium containing alkali metal chlorate and sulfate; reducing chlorate ions in said reaction medium to form chlorine dioxide; withdrawing chlorine dioxide gas from the reaction medium; withdrawing reaction medium from the reactor and transferring it to an electrochemical cell substantially without crystallization of sulfate or chlorate; electrochemically acidifying said reaction medium to increase the acidity and to decrease the content of alkali metal ions; recycling acidified reaction medium to the reactor; adding make up alkali metal chlorate to the reaction medium before or after the electrochemical cell; wherein the current efficiency of the electrochemical cell is maintained below about 80 %.</p> |
