A Kinetic-Potentiometric Method for the Simultaneous Determination of Hydrazine and Acetylhydrazine

Simultaneous determination of hydrazine (HZ) and acetylhydrazine (AHZ) by H-point standard addition method (HPSAM) and partial least squares (PLS) regression was carried out based on kinetic data of novel potentiometry. The rate of chloride ion production in reaction of HZ and AHZ with N-chlorosuccinimide (NCS) was monitored by a chloride ion-selective electrode. The experimental dada shows not only the good ability of ion-selective electrodes (ISEs) as a detector for the direct determination of chloride ion but also for simultaneous kinetic-potentiometric analysis using HPSAM and PLS methods. The methods are based on the differences observed in the production rate of chloride ions. The results show that simultaneous determination of HZ and AHZ can be performed in their concentration ranges of 0.4-10.0 and 2.0-20.0 mu g mL(-1), respectively. The total relative standard error for applying the PLS method to 9 synthetic samples in the concentration ranges of 0.0-9.0 mu g mL(-1) for HZ and 2.0-20.0 mu g mL(-1) for AHZ was 2.00. In order for the selectivity of the method to be assessed, the effects of certain foreign ions upon the reaction rate were evaluated and determined. Both methods (HPSAM and PLS) were evaluated using a set of synthetic sample mixtures and then applied for simultaneous determination of HZ and AHZ in water samples.