IMPROVEMENTS IN THE METHOD OR PROCESS OF TREATING ORES AND SUBSTANCES CONTAINING ANTIMONY AND OTHER METALS FOR THE RECOVERY THEREOF
Year: 1883

page_text: PROVISIONAL SPECIFICATION left by John Cope Butterfield at the Office
of the Commissioners of Patents on the 13th June 1883.
JOHN COPE BUTTERFIELD of Westminster Chambers in the City of Westminster
"IMPROVEMENTS IN THE METHOD OR PROCESS OF TREATING ORES AND SUBSTANCES
CONTAINING ANTIMONY AND OTHER METALS FOR THE RECOVERY THEREOF "
The invention relates more especially to the treatment of Ores of Antimony and
other substances containing antimony (in which the metal occurs as sulphide)
which are more or less contaminated with gangue, (quartz &c), and also to ores.
of antimony containing silver or gold.
The principal objects are to obtain metallic Antimony at a less cost, and free
from sulphur and Iron than by the usual method of treating in furnaces with
admixture of metallic Iron, also by my invention the great loss of metal arising
from the many furnace operations now in use is avoided, and the sulphur is
economised also the solution of Perchloride of Iron used as a solvent, is recovered
by a simple chemical and well-known process rendered available for further use
In carrying the invention into practice, first the ores are finely ground to
powder, by any suitable machinery, I prefer to first reduce the ore by means of a
stone crusher to coarse powder-this is then reduced to impalpable powder, either
by edge runners or by one of the many machines in use for that purpose-the
finely ground ore is then sifted through a sieve of 90 or 100 holes to the linear
inch
The finely ground ore is then placed in tanks of wood or of earthenware, each
of which is provided with a system of pipes either of earthenware or type metal
by which the tanks may be heated by superheated steam-I prefer to employ 4
tanks arranged one above the other-each is supplied with the proper quantity of
ore, and to the topmost one I add a strong hot solution of Perchloride of Iron
(about 70 T) and boil with frequent stirring-The perchloride of Iron is reduced
by the Antimonus Sulphide to Ferrous Chloride whilst the antimony is dissolved
as chloride with a separation of sulphur. Afer boiling I run the hot solution
from the highest tank to the next one below and boil again on a fresh lot of ore
thus I can if necessary reduce the whole of the Ferric chloride to Ferrus chloride,
but prefer to keep a slight excess of Fe, Cl, (perchloride) in solution-when the
solution of Ferrous chloride, containing antimonous chloride has a gravity of

page_text: 104 T it is nearly saturated with Sb Cl, (antimony chloride)-I then run off such
solution into a large wooden vat and allow to settle, taking care that the solution
is not of such a strength as to deposit crystals on cooling To the first (or N° 1
Tank) I now add fresh solution of Perchloride of Iron and boil again, passing such
solution on to N° 2 and so on to N° 3 until it in its turn becomes saturated-I
repeat this operation a sufficient number of times with each tank to insure the
decomposition of the ore, and at the same time washing the gangue free from the
antimonous solution The residue (or gangue) remaining in the tanks (which
may contain gold, or minerals containing Gold and silver not decomposable by
Perchloride of Iron,-) is washed out through a large hole left in the bottom of
the tank and while the tank is in use closed by a suitable valve or plug for the
purpose into a convenient receptacle and if it contains any valuable metal is
treated by any economical method for the extraction of the same
The clear saturated solution of Ferro-antimonius chloride is run out of the
settling tank into the precipitating vat, in which is a coil of pipe for heating-the
solution is made to boil, and a little Hydrochloric acid added-scrap Iron is then
introduced, (preferably suspended in a wooden cage) The Iron displaces the
antimony in the solution, giving metallic antimony and forming Ferrus chloride-
this action continues until the whole of the antimony is precipitated the solution
must be kept hot not quite at the boiling point but nearly so-as the reaction
takes place much better when hot On the completion of the operation-steam is
shut off, and the whole allowed to rest, the clear Ferrous chloride is run into a
large wooden vat-chloride of lime is added and a little H Cl or chlorine evolved
from manganese oxide and Hydrochloric acid is passed through the solution, or it
may be oxidised by passing hot air or in other convenient manner-in any case the
Ferrous ehloride is re-oxidised to Ferric chloride which is then pumped backed into
the tanks for further use-As the quantity of Ferric chloride in this way will
increase after every operation the excess of it may be got rid of in a profitable
manner by precipitating the chloride of iron with carbonate of Lime or Lime; thus
producing oxide of Iron which may be preferred, dried and heated and thus
converted into paint or a material for gas purposes.
The metallic antimony (after removing the Ferrous chloride) remains at the
bottom of the vat, and is washed with a little acid (H Cl) and water) until the
washings are practically free from Iron salts it is then run out of the tank on to
rough linen filters or equivalent filtering medium and dried at a very low
temperature, or it may be compressed by bydraulic or other pressure into cakes
and afterwards melted into ingots