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Controlling the Formation of Chlorate Ion in Liquid Hypochlorite Feedstocks
Author(s) -
Gordon Gilbert,
Adam Luke C.,
Bubnis Bernard P.,
Hoyt Brian,
Gillette Stephen J.,
Wilczak Andrzej
Publication year - 1993
Publication title -
journal ‐ american water works association
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.466
H-Index - 74
eISSN - 1551-8833
pISSN - 0003-150X
DOI - 10.1002/j.1551-8833.1993.tb06065.x
Subject(s) - hypochlorite , chlorate , dilution , chemistry , decomposition , raw material , inorganic chemistry , calcium hypochlorite , chlorine , chromatography , organic chemistry , thermodynamics , physics
Experiments were carried out to confirm the presence of chlorate ion (ClO 3 − ) in the treated water of utilities that use hypochlorination. Sixteen commercially produced, concentrated liquid hypochlorite feedstocks were analyzed for ClO 3 − , and levels as high as 158 g percent ClO 3 − relative to hypochlorite ion were measured. Finished‐water samples from the utilities surveyed contained as much as 0.30 mg ClO 3 − /L, primarily the result of decomposition of the liquid hypochlorite feedstocks. Although both dilution and lower temperatures can be effective in minimizing ClO 3 − formation, it was observed that diluting the initial liquid hypochlorite concentration by a factor of 2 is more effective than decreasing the temperature from 24 to 10°C. A methodology is proposed that predicts the dilution or temperature reduction (or both) required to avoid significant ClO 3 − formation in the feedstock solutions.