Catalyzed and uncatalyzed decomposition of hypochlorite in dilute solutions
2015 (English)In: Industrial & Engineering Chemistry Research, ISSN 0888-5885, E-ISSN 1520-5045, Vol. 54, no 15, 3767-3774 p.Article in journal (Refereed) Published
Hypochlorite decomposition has been investigated by the combined measurement of aqueous concentrations of total hypochlorite, chlorate, and chloride, as well as that of evolved oxygen. In all experiments, the initial concentrations of NaOCl and NaCl were 80 mM, and the temperature was 80°C. The pH was kept constant in the range 5-10.5. The uncatalyzed decomposition of hypochlorite and the formation of chlorate and oxygen were all found to be third order of the form r<inf>i</inf> = k<inf>i</inf>[HOCl]2[OCl-], and k<inf>O</inf><inf>2</inf> was determined to be 0.046 M-2 s-1. A reaction mechanism in which oxygen and chlorate formation share an intermediate is proposed. Several compounds were tested for catalytic effects. The addition of chloride salts of cobalt and iridium showed catalytic effects on oxygen formation. The addition of iridium chloride also catalyzed the formation of chlorate with increasing selectivity for chlorate with increasing pH.
Place, publisher, year, edition, pages
2015. Vol. 54, no 15, 3767-3774 p.
Catalysis, Chlorine compounds, Iridium, Reaction intermediates, Aqueous concentrations, Catalytic effects, Chlorate formation, Chloride salts, Combined measurements, Dilute solution, Initial concentration, Reaction mechanism, Oxygen
Other Chemical Engineering
IdentifiersURN: urn:nbn:se:kth:diva-167744DOI: 10.1021/ie504890aISI: 000353929300005ScopusID: 2-s2.0-84928485256OAI: oai:DiVA.org:kth-167744DiVA: diva2:815601
FunderSwedish Energy Agency
QC 201506012015-06-012015-05-222015-11-19Bibliographically approved