AWWA JAW60489 Journal AWWA - Chlorite Ion Interference in the Spectrophotometric Measurement of Chlorine Dioxide

Journal Article by American Water Works Association, 09/01/2004

Kortvelyesi, Zsolt; Gordon, Gilbert

Full Description

Chlorine dioxide (ClOsub2/sub) is used at many water treatmentplants for disinfecting potable water. In suchapplications, having a simple, convenient, and reliableanalytical method to measure the concentration ofClOsub2/sub can simplify the use of it as a disinfectant. However,the presence of the Clsub2/subOsub4/subsup-/sup complex, which forms inClOsub2/sub solutions in the presence of chlorite ion, can resultin significant error in the spectrophotometric measurementof ClOsub2/sub. In this article, the authors demonstrate thesignificance of the Clsub2/subOsub4/subsup-/sup complex and report the formationconstant (Ksubeq/sub) and the molar absorptivity of thiscomplex. Based on the Ksubeq/sub and the molar absorptivityvalues, the authors propose two methods to correct for thepresence of the complex and suggest the use of one equationin particular. By using the equation suggested, theauthors demonstrate that the error of the determinedClOsub2/sub concentrations is reduced to the level of errors associatedwith the spectrophotometric measurements. Includes 16 references, tables, figures.

Product Details

Edition: Vol. 96 - No. 9 Published: 09/01/2004 Number of Pages: 7 File Size: 1 file , 120 KB