DETERMINATION OF CHLORINE DIOXIDE BY ULTRAVIOLET SPECTROPHOTOMETERY

摘要

PURPOSE:To enable continuous determination of chlorine dioxide by a method wherein a pH buffer agent is mixed into an aqueous solution of chlorine dioxide to liberate chlorine dioxide, and the gas contg. chlorine dioxide voltalized from the aq. soln. by passing an inert gas is determined by an ultraviolet ray spectrophotometry method. CONSTITUTION:A water solution 1 of chlorine dioxide and a normal solution comprising tartaric acid and sodium tartrate at a ratio of 1/10 each are mixed at the ratio by volume of 1:20. The mixture is mixed with a buffer liquid 2 of pH4.2 at an equal flow rate and fed into a chlorine dioxide generation tank 4 at a weak acidity of pH5.0+ or -1.0. The mixture is retained at a temperature of 50 deg.C to liberate chlorine dioxide while air is blown thereinto from an air injection pipe 5 provided on the bottom of the tank 4 to make chlorine dioxide fugacious. After cooled to 20 deg.C with a cooling tube 6, a gas thus obtained is sent to a detector 7. An inert gas containing chlorine dioxide with separated entrainment is measured by a peak wavelength 360nm of absorptivity for chlorine dioxide.