JPS6329218B

To compensate the zero-point drifts in continuous measuring processes using redox or ion-sensitive electrodes, a side stream is branched off from the system to be measured and potentiometric measurement is carried out therein in such a way that, after potentiometric measurement of the momentary concentration of the ions to be determined, the zero point is re-determined after complete removal of this ion type with a suitable reagent. Both measurements are best carried out with the assistance of a timer. The system may for example be applied to the measurement of the cyanide ion content of a solution using hydrogen peroxide as the reagent.