A STUDY OF THE STABILITY OF ZIRCONIUM AND HAFNIUM TETRAHALIDES ON HITTING A HOT SURFACE IN VACUUM

Journal Article · Sat Sep 01 00:00:00 EDT 1962 · Doklady Akademii Nauk SSSR (U.S.S.R.) English translation currently published in a number of subject-oriented journals

OSTI ID:4797121

Tsirel'nikov, V I; Komissarova, L N; Spitsyn, V I

The decomposition coefficients of the chlorides, bromides, and iodides of Zr and Hf were determined as a function of the temperature of a hot surface. The tetrahalides were carefully purified in an inert atmosphere of argon. The halide compound in a quartz ampoule was heated by a removable heater. The vapors passed through a capillary opening and struck a tungsten foil 0.5 mm thick and 12 to 15 mm wide. The Mo foil was heated electrically to control the surface temperature which was measured by an optical pyrometer. The tetrahalide decomposed according to the following reaction: Me(Hal)/sub 4/ yields Me + 2(Hal)/sub 2/. The lower halides dissociated completely to metal and free halides, since the temperature was >600 deg C. The Mo backing was dissolved in nitric acid, and the unsupported metal deposit of Zr or Hf was weighed, The decomposition coefficient was calcuweight of metal evaporated. Zrl/sub 4/ decomposed completely (100%) at 1500 deg C, while only 96% of the HfI/sub 4/ was decomposed at this temperature. The ZrBr/sub 4/ and HfBr/sub 4/ were decomposed by 68 and 61% respectively. The ZrCl/sub 4/ and HfCl/sub 4/ were stable at l500 deg C (5% of the ZrCl/sub 4/ was decomposed at l500 deg C). In all cases, the hafnium halide was more stable than the zirconium halide, especially in the case of the iodides. The decomposition was directly proportional to the temperature of the molybdenum target. (TTT)

• Research Organization: Moscow Univ.
• NSA Number: NSA-17-000159
• OSTI ID: 4797121
• Journal Information: Doklady Akademii Nauk SSSR (U.S.S.R.) English translation currently published in a number of subject-oriented journals, Vol. Vol: 146; Other Information: Orig. Receipt Date: 31-DEC-63
• Country of Publication: Country unknown/Code not available
• Language: Russian

Related Subjects

CHEMISTRY
ARGON
CAPILLARIES
DECOMPOSITION
FOILS
HAFNIUM
HAFNIUM BROMIDES
HAFNIUM CHLORIDES
HAFNIUM IODIDES
HEATING
IMPURITIES
INERT GASES
MEASURED VALUES
MOLYBDENUM
NITRIC ACID
OPTICAL SYSTEMS
QUANTITATIVE ANALYSIS
QUARTZ
RESIDUES
SOLUTIONS
SURFACES
TEMPERATURE
TUNGSTEN
VESSELS
ZIRCONIUM
ZIRCONIUM BROMIDES
ZIRCONIUM CHLORIDES
ZIRCONIUM IODIDES