Generation of ruthenium dioxide powders during thermal decomposition of Ru(OH)/sub 4/ in a vibrofluidized bed

Journal Article · Thu Oct 20 04:00:00 EDT 1988 · J. Appl. Chem. USSR (Engl. Transl.); (United States)

OSTI ID:6368283

Shorikov, Yu S; Sbitnev, V L; Ermolaev, V N; Sharipova, N S; Fasman, A B; Orlov, A M

In an earlier paper the authors examined thermal conversions of Ru(OH)/sub 4/, leading under static conditions at 650-700/sub 0/ to formation of RuO/sub 2/ with predominant specific surface (S) of 4-10/sup 2/ m/sup 2//g. In this case formation of ultrafine powders (S greater than or equal to 20 m/sup 2//g) of uniform particle-size composition is limited by collective recrystallization and sintering processes occurring during direct contact of the particles. The purpose of the present work was to study the relationships of formation of RuO/sub 2/ powders during thermal decomposition of Ru(OH)/sub 4/ in a fluidized state. Thermal conversions of Ru(OH)/sub 4/ pass through the same stages as in a stationary bed with formation of a highly defective RuO/sub 2/ phase; recrystallization of the first kind begins in that phase after transformation of the spongy microstructure into a mixture of microcrystals. Heating of ruthenium(IV) hydroxide under dynamic conditions hinders sintering and collective recrystallization processes, making it possible to obtain fine ruthenium dioxide powders of more uniform particle-size composition than is obtainable under static conditions.

• OSTI ID: 6368283
• Journal Information: J. Appl. Chem. USSR (Engl. Transl.); (United States), Journal Name: J. Appl. Chem. USSR (Engl. Transl.); (United States) Vol. 61:5; ISSN JAPUA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360202* -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
CHALCOGENIDES
CHEMICAL REACTIONS
COHERENT SCATTERING
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
CRYSTAL-PHASE TRANSFORMATIONS
DECOMPOSITION
DIFFRACTION
ELECTRON DIFFRACTION
FABRICATION
FINE STRUCTURE
FLUIDIZED BEDS
HYDROGEN COMPOUNDS
HYDROXIDES
LATTICE PARAMETERS
MECHANICAL VIBRATIONS
MICROSTRUCTURE
OXIDES
OXYGEN COMPOUNDS
PARTICLE SIZE
PHASE TRANSFORMATIONS
POWDERS
PYROLYSIS
RECRYSTALLIZATION
REFRACTORY METAL COMPOUNDS
RUTHENIUM COMPOUNDS
RUTHENIUM HYDROXIDES
RUTHENIUM OXIDES
SCATTERING
SINTERING
SIZE
SYNTHESIS
TEMPERATURE EFFECTS
THERMOCHEMICAL PROCESSES
TRANSITION ELEMENT COMPOUNDS
X-RAY DIFFRACTION