SEPARATION OF IRON FROM NICKEL AND COBALT. 157 
THE SEPARATION oF IRON FRom NICKEL anpD COBALT 
BY LEAD OXIDE (FIELD’s METHOD). 
By TT. H. Lasy, Junior Demonstrator of Chemistry, 
University of Sydney. 
{Communicated by Professor LIVERSIDGE, M.A.,LL.D.,F.R.S. | 
[Read before the Royal Society of N. S. Wales, September 2, 1903. ] 
Review of Methods for the Separation of Iron from Nickel 
and Cobalt. 
1. Ammonium Hydrate and Chloride. 
The precipitation of ferric salts by ammonium hydrate 
in the presence of ammonium chloride gives an incomplete 
separation—according to Moore’ an absolutely worthless 
one. No experimental work on the reprecipitations neces- 
sary for accuracy was found. Fresenius states three to be 
necessary. Baumhauer’? is said to have found that ferric 
hydrate may occlude 27% of nickel and 48% of cobalt. 
2. Ammonium Carbonate (Schwarzenberg’). 
To the solution of the chlorides, containing ammonium 
chloride equal to twenty times the weight of the oxide of 
nickel present ammonium carbonate is added to a point 
specified in Schwarzenberg’s paper, and quoted by Fresenius. 
The success of the method depends on striking a point 
difficult to ascertain. The method, however, is recom- 
mended by Fresenius and others. The writer inan analysis 
of a meteoric iron, found it to be a long and tedious separa- 
tion; and the amount of nickel found being lower than by 
Field’s method, partly owing to a slight loss in the pre- 
* Chemical News, 1892, uxv., p. 75. 
? Archives fur Néerlandaises, 1879, Vol. v1.—(Reference not verified.) 
* Liebig’s Annal. xivu., p. 216; also Chem. Gaz., 1856. 
