Phase transitions in coprecipitated NiO-WO/sub 3/ system in calcination, reduction, and sulfiding

Journal Article · Tue Apr 01 00:00:00 EST 1986 · Kinet. Catal. (Engl. Transl.); (United States)

OSTI ID:6157522

Agievskii, D A; Pavlova, L I; Landau, M V; Kvashonkin, V I; Chukin, G D

X-ray diffraction and electron microscopy have been used in an investigation of the shaping of phase composition and structure of a coprecipitated NiO-WO/sub 3/ system in calcination, reduction, and sulfiding. It has been shown that calcination, when it leads to the formation of crystalline NiWO/sub 4/, lowers the efficiency of reduction and sulfiding to a considerable degree. A step-temperature sulfiding operation, in comparison with isothermal sulfiding, gives a less ordered structure of the WS/sub 2/, with loose packing of the particles into agglomerates.

• Research Organization: All-Union Scientific-Research Institute for Petroleum Processing, Moscow, USSR
• OSTI ID: 6157522
• Journal Information: Kinet. Catal. (Engl. Transl.); (United States), Vol. 26:5; Other Information: Translated from Kinet. Katal.; 26: No.5, 1207-1212(Sep-Oct 1985)
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
36 MATERIALS SCIENCE
NICKEL OXIDES
CATALYTIC EFFECTS
CRYSTAL-PHASE TRANSFORMATIONS
STRUCTURAL CHEMICAL ANALYSIS
TUNGSTEN OXIDES
CALCINATION
CATALYSTS
COPRECIPITATION
CRYSTAL STRUCTURE
ELECTRON MICROSCOPY
HEAT TREATMENTS
HYDROCARBONS
HYDROGENATION
NICKEL SULFIDES
NICKEL TUNGSTATES
QUANTITY RATIO
REDUCTION
SULFIDATION
TEMPERATURE EFFECTS
TUNGSTEN SULFIDES
X-RAY DIFFRACTION
CHALCOGENIDES
CHEMICAL REACTIONS
COHERENT SCATTERING
DECOMPOSITION
DIFFRACTION
MICROSCOPY
NICKEL COMPOUNDS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
PRECIPITATION
PYROLYSIS
REFRACTORY METAL COMPOUNDS
SCATTERING
SEPARATION PROCESSES
SULFIDES
SULFUR COMPOUNDS
THERMOCHEMICAL PROCESSES
TRANSITION ELEMENT COMPOUNDS
TUNGSTATES
TUNGSTEN COMPOUNDS
400201* - Chemical & Physicochemical Properties
360202 - Ceramics
Cermets
& Refractories- Structure & Phase Studies