The characteristics of passivated iron particles have been examined with flow microcalorimetry to determine the acidic nature of the surface sites. The molar heat of adsorption of pyridine from hexane was measured with a FMC and a differential refractive index detector, at 23 and 40°C. The adsorption data were found to obey the assumptions of the Freundlich isotherm. The adsorption densities at different temperatures were used to calculate the isosteric heat of adsorption. The molar heat of adsorption of triethylamine from hexane was also measured and combined with the data for pyridine in order to calculate the Drago constants for the iron particles. A static adsorption method was used for the adsorption of pyridine from hexane onto the iron particles, for comparison with the dynamic method. The heat of wetting for the iron particles, with hexane, has also been measured. The iron particles were examined with X-ray diffraction. Mossbauer spectroscopy, XPS, SEM, TEM, and electrophoresis to characterize the surface layer. These techniques have revealed that the iron particles are coated with ferric oxide and this surface is amphoteric in aqueous solutions.
| Identifer | oai:union.ndltd.org:arizona.edu/oai:arizona.openrepository.com:10150/276614 |
| Date | January 1987 |
| Creators | Andrews, Marilyn Mockus, 1958- |
| Contributors | Raghavan, Srini |
| 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. |
Page generated in 0.0049 seconds