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FIZIKA A 4 (1995) 2, 309-314
 
PREPARATION OF NICKEL POWDERS IN NONAQUEOUS MEDIA
JADRAN MAČEK and ANDREJ DEGEN
University of Ljubljana, Faculty of Chemistry and Chem. Technology, Aškerčeva 5,
P.O.B. 537, 61000 Ljublana, Slovenia
Received 7 April 1995
Revised manuscript received 5 June 1995
Precipitation of nickel powder is usually carried out in aqueous media. Nonaqueous
solvents such as ethanolamines offer several advantages. The effective temperature range
extends to the higher temperatures needed for the reduction of nickel at atmospheric
pressure, a reaction that is also facilitated by the basicity of the medium. Tests were
carried out for the preparation of submicrometre nickel powders by the reduction of metal
salts using various ethanolamines (monoethanolamine - MEA, diethanolamine - DEA, and
triethanolamine - TEA) as solvents. Hydrazine (N2H4) was used as the
reducing agent. The basicity, polarity, viscosity and boiling point of the reaction medium
all affect the reactions. By changing the reaction conditions and the anionic component of
the precursor salt, it was possible to alter the purity and morphology of the nickel
powders obtained and the average particle size, except in the case of MEA where no
reduction occured. The products were subsequently characterised by chemical analysis and
by scanning electron microscopy.
UDC 621.762.2
PACS 82.30.Nr
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