METHOD FOR SPECTROPHOTOMETRIC DETERMINATION OF CONCENTRATION OF CHLORINE DIOXIDE AND CHLORITE IONS IN DRINKING WATER Russian patent published in 2013 - IPC G01N21/27 

FIELD: chemistry.

SUBSTANCE: method involves treating a water sample with potassium iodide solution; successive measurement of optical density of a chlorine dioxide sample at pH=7 and chlorite ions and chlorine dioxide at pH=2.5; determining from calibrated curves concentration of chlorine dioxide at pH=7 and total concentration of chlorite ions and chlorine dioxide at pH=2.5; calculating concentration of the chlorite ions using the formula: $$\left(\frac{C_2}{\mathrm{16,86}}-\frac{C_1}{\mathrm{67,46}}\right)\times \mathrm{16,86,}$$ where C₁ is concentration of chlorine dioxide at pH=7, mg/dm³; C₂ is total concentration of chlorine dioxide and chlorite ions at pH=2.5, mg/dm³; 67.46 is the oxidative equivalent of chlorine dioxide corresponding to pH=7; 16.86 is the oxidative equivalent of chlorite ions corresponding to pH=2.5.

EFFECT: invention enables to cut analysis time and increases reliability of results thereof.