A detailed study has been carried out to investigate the dissolution characteristics of unstabilized and stabilized CrO₂ particles. It has been found that on contact of CrO₂ with aqueous solutions, it dissolves by disproportionation reaction to HCrO₄ and Cr2O₃. XPS study has shown that stabilization of CrO₂ particles with bisulfite solution leads to the formation of Cr2O₃. However, because of agglomeration of the CrO₂ particles due to their magnetic properties, not all of the surface is completely stabilized. The electrokinetic characteristics of Cr(IV) and Cr(III) oxides in aqueous solutions have been investigated. Experiments suggest that sulfite ions chemisorb strongly on Cr₂O₃ particles. Experiments have also been carried out to study the adsorption of sodium dodecyl sulfate (SDS) on Cr₂O₃ particles. With increasing SDS concentration, Cr₂O₃ becomes less positively charged and ultimately negatively charged when the surfactant concentration exceeds 10⁻³ M. This suggests that SDS specifically adsorbs onto the oxide.
Identifer | oai:union.ndltd.org:arizona.edu/oai:arizona.openrepository.com:10150/276486 |
Date | January 1987 |
Creators | Ali, Iqbal, 1948- |
Publisher | The University of Arizona. |
Source Sets | University of Arizona |
Language | en_US |
Detected Language | English |
Type | text, Thesis-Reproduction (electronic) |
Rights | Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author. |
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