SEPARATION OF RARE EARTH ELEMENTS. VII. STUDY OF THE SYSTEM OF PRASEODYMIUM OXIDENEODYMIUM OXIDE (DETERMINATION OF LABILE OXYGEN)
Journal Article
·
· Journal fuer Praktische Chemie (East Germany)
In order to determine the labile O bonded to the higher oxide of Pr, a method consisting of the measurement of the volume of O/sub 2/ liberated from the reaction 4PrO/sub 2/ + 12H/sup +/ yields 4Pr/sup 3+/ + 6H/sub 2/O + O/sub 2/ was employed. The Pr (4+) content in the mixture of Pr and Nd oxides may be calculated from the O/sub 2/ volume measurements. The oxides were dissolved in dil. HNO/sub 3/. The quantity of liberated O/sub 2/ was measured from the volume increase of the reaction apace, confined by very pure mercury placed in a U-tube. One of the arms of the U-tube serves as a reading scale. The mixture of Pr and Nd oxides was heated for 12 hours at 800 to 1200 deg C prior to chemical analysis. After such a treatment, the PrO/sub 2/ content in the oxide mixtures, containing various proportions of the components, is an increasing function of the Nd/sub 2/O/sub 3/ content of the studied system. As a further check on the results of x-ray structure analysis, the above result indicates that Nd/sub 2/O/ sub 3/ has a beneficial effect on the forrmation of PrO/sub 2/ in mixed crystals, with a fluorite type lattice. It is believed that Nd/sub 2/O/sub 3/ forms mixed crystals with Pr/sub 6/O/sub 11/ as a result of the isomorphic substitution of Pr sesquioxide contained in its lattice. Displaced Pr/sub 2/O/sub 3/ is oxidized to PrO/sub 2/ by oxygen of the air. The content of labile oxygen in mixed fluorite type crystals depends to a large extent upon the conditions of the mixture's cooling subsequent to their heating. In mix- tures with high Nd content, the phase correspondence and the amount of displaced O depend, in the main, on the conditions of roasting. In the latter case the basic component of the mixture is a hexagonal A-form of sesquioxides, which improves the mixed oxide's stability to action by the air's oxygen. (W.L.H.)
- Research Organization:
- Originating Research Org. not identified
- Sponsoring Organization:
- USDOE
- NSA Number:
- NSA-14-013706
- OSTI ID:
- 4190836
- Journal Information:
- Journal fuer Praktische Chemie (East Germany), Journal Name: Journal fuer Praktische Chemie (East Germany) Vol. Vol: 6; ISSN JPCEA
- Country of Publication:
- Country unknown/Code not available
- Language:
- English
Similar Records
Solvolytic disproportionation of mixed-valence compounds. I. Pr/sub 7/O/sub 12/
THE SOLID STATE CHEMISTRY OF RARE EARTH OXIDES. Technical Progress Report
Preparation and structural study from neutron diffraction data of Pr{sub 5}Mo{sub 3}O{sub 16}
Journal Article
·
Fri Jul 01 00:00:00 EDT 1988
· J. Solid State Chem.; (United States)
·
OSTI ID:7044799
THE SOLID STATE CHEMISTRY OF RARE EARTH OXIDES. Technical Progress Report
Technical Report
·
Thu Jul 12 00:00:00 EDT 1962
·
OSTI ID:4818737
Preparation and structural study from neutron diffraction data of Pr{sub 5}Mo{sub 3}O{sub 16}
Journal Article
·
Tue Dec 14 23:00:00 EST 2010
· Journal of Solid State Chemistry
·
OSTI ID:21494154
Related Subjects
AIR
BONDING
CALCIUM FLUORIDES
CHEMISTRY
CONFIGURATION
COOLING
CRYSTALS
FLUORITE
HEATING
LATTICES
MEASURED VALUES
MERCURY
MIXING
NEODYMIUM OXIDES
NITRIC ACID
OXIDATION
OXYGEN
PRASEODYMIUM OXIDES
QUALITATIVE ANALYSIS
QUANTITATIVE ANALYSIS
RARE EARTHS
SEPARATION PROCESSES
STABILITY
STANDARDS
TEMPERATURE
TUBES
VOLUME
X RADIATION
BONDING
CALCIUM FLUORIDES
CHEMISTRY
CONFIGURATION
COOLING
CRYSTALS
FLUORITE
HEATING
LATTICES
MEASURED VALUES
MERCURY
MIXING
NEODYMIUM OXIDES
NITRIC ACID
OXIDATION
OXYGEN
PRASEODYMIUM OXIDES
QUALITATIVE ANALYSIS
QUANTITATIVE ANALYSIS
RARE EARTHS
SEPARATION PROCESSES
STABILITY
STANDARDS
TEMPERATURE
TUBES
VOLUME
X RADIATION