Mathematical model of the catalytic effect of chromium(VI) on hypochlorite disproportionation in chlorate electrolysis
Abstract
The effect of chromium(VI) on the kinetics of disproportionation of hypochlorous acid and hypochlorite was established in the solution for the electrolytic production of chlorate. The hexavalent chromium species Cr2O7 2-, HCrO4 - and CrO4 2- present in the solution catalyze the disproportionation reaction. In both the absence and presence of chromium(VI), disproportionation is a third-order reaction with respect to HClO and ClO-P, and a first-order reaction with respect to the hexavalent chromium species. In the presence of chromium(VI) ions, four parallel reactions probably take place in the solution i.e. uncatalyzed disproportionation and three parallel reactions catalyzed by Cr2O7 2-, HCrO4 - and CrO4 2-ions. Most likely, the hexavalent chromium species do not change the sequence of elementary reactions in the disproportionation mechanism but only speed up the rate-determining step through interaction with its reactants. In the chlorate production process, as chromium(VI) concentrat...ion increases, the optimum pH which ensures the maximum rate of disproportionation is shifted to an acid environment. This is due to an increase in the concentration of the catalytically most active species HCrO4 - with increasing acidity of the solution. A mathematical model of the kinetics of the chromium(VI)-catalyzed disproportionation of hypochlorite and hypochlorous acid into chlorate was set up. Good agreement was obtained between theoretical and experimental data. © 2018 The Electrochemical Society.
Source:
Journal of the Electrochemical Society, 2018, 165, 2, E8-E19Publisher:
- Pennington N.J. : Electrochemical Society
Funding / projects:
Note:
- Peer-reviewed manuscript: https://hdl.handle.net/21.15107/rcub_dais_8970
DOI: 10.1149/2.0291802jes
ISSN: 0013-4651
WoS: 000431786800089
Scopus: 2-s2.0-85043601638
Institution/Community
Институт техничких наука САНУ / Institute of Technical Sciences of SASATY - JOUR AU - Spasojević, Miroslav AU - Marković, D. AU - Trišović, Tomislav AU - Spasojević, Milica PY - 2018 UR - https://dais.sanu.ac.rs/123456789/3750 AB - The effect of chromium(VI) on the kinetics of disproportionation of hypochlorous acid and hypochlorite was established in the solution for the electrolytic production of chlorate. The hexavalent chromium species Cr2O7 2-, HCrO4 - and CrO4 2- present in the solution catalyze the disproportionation reaction. In both the absence and presence of chromium(VI), disproportionation is a third-order reaction with respect to HClO and ClO-P, and a first-order reaction with respect to the hexavalent chromium species. In the presence of chromium(VI) ions, four parallel reactions probably take place in the solution i.e. uncatalyzed disproportionation and three parallel reactions catalyzed by Cr2O7 2-, HCrO4 - and CrO4 2-ions. Most likely, the hexavalent chromium species do not change the sequence of elementary reactions in the disproportionation mechanism but only speed up the rate-determining step through interaction with its reactants. In the chlorate production process, as chromium(VI) concentration increases, the optimum pH which ensures the maximum rate of disproportionation is shifted to an acid environment. This is due to an increase in the concentration of the catalytically most active species HCrO4 - with increasing acidity of the solution. A mathematical model of the kinetics of the chromium(VI)-catalyzed disproportionation of hypochlorite and hypochlorous acid into chlorate was set up. Good agreement was obtained between theoretical and experimental data. © 2018 The Electrochemical Society. PB - Pennington N.J. : Electrochemical Society T2 - Journal of the Electrochemical Society T1 - Mathematical model of the catalytic effect of chromium(VI) on hypochlorite disproportionation in chlorate electrolysis SP - E8 EP - E19 VL - 165 IS - 2 DO - 10.1149/2.0291802jes UR - https://hdl.handle.net/21.15107/rcub_dais_3750 ER -
@article{ author = "Spasojević, Miroslav and Marković, D. and Trišović, Tomislav and Spasojević, Milica", year = "2018", abstract = "The effect of chromium(VI) on the kinetics of disproportionation of hypochlorous acid and hypochlorite was established in the solution for the electrolytic production of chlorate. The hexavalent chromium species Cr2O7 2-, HCrO4 - and CrO4 2- present in the solution catalyze the disproportionation reaction. In both the absence and presence of chromium(VI), disproportionation is a third-order reaction with respect to HClO and ClO-P, and a first-order reaction with respect to the hexavalent chromium species. In the presence of chromium(VI) ions, four parallel reactions probably take place in the solution i.e. uncatalyzed disproportionation and three parallel reactions catalyzed by Cr2O7 2-, HCrO4 - and CrO4 2-ions. Most likely, the hexavalent chromium species do not change the sequence of elementary reactions in the disproportionation mechanism but only speed up the rate-determining step through interaction with its reactants. In the chlorate production process, as chromium(VI) concentration increases, the optimum pH which ensures the maximum rate of disproportionation is shifted to an acid environment. This is due to an increase in the concentration of the catalytically most active species HCrO4 - with increasing acidity of the solution. A mathematical model of the kinetics of the chromium(VI)-catalyzed disproportionation of hypochlorite and hypochlorous acid into chlorate was set up. Good agreement was obtained between theoretical and experimental data. © 2018 The Electrochemical Society.", publisher = "Pennington N.J. : Electrochemical Society", journal = "Journal of the Electrochemical Society", title = "Mathematical model of the catalytic effect of chromium(VI) on hypochlorite disproportionation in chlorate electrolysis", pages = "E8-E19", volume = "165", number = "2", doi = "10.1149/2.0291802jes", url = "https://hdl.handle.net/21.15107/rcub_dais_3750" }
Spasojević, M., Marković, D., Trišović, T.,& Spasojević, M.. (2018). Mathematical model of the catalytic effect of chromium(VI) on hypochlorite disproportionation in chlorate electrolysis. in Journal of the Electrochemical Society Pennington N.J. : Electrochemical Society., 165(2), E8-E19. https://doi.org/10.1149/2.0291802jes https://hdl.handle.net/21.15107/rcub_dais_3750
Spasojević M, Marković D, Trišović T, Spasojević M. Mathematical model of the catalytic effect of chromium(VI) on hypochlorite disproportionation in chlorate electrolysis. in Journal of the Electrochemical Society. 2018;165(2):E8-E19. doi:10.1149/2.0291802jes https://hdl.handle.net/21.15107/rcub_dais_3750 .
Spasojević, Miroslav, Marković, D., Trišović, Tomislav, Spasojević, Milica, "Mathematical model of the catalytic effect of chromium(VI) on hypochlorite disproportionation in chlorate electrolysis" in Journal of the Electrochemical Society, 165, no. 2 (2018):E8-E19, https://doi.org/10.1149/2.0291802jes ., https://hdl.handle.net/21.15107/rcub_dais_3750 .