Improvements in the Method of and Means for Obtaining Copper from Copper Ores.
Year: 1896

page_text: Date of Application, 4th May, 1896
Complete Specification Left, 22nd Aug., 1896-Accepted, 17th Oct., 1896
PROVISIONAL SPECIFICATION.
Improvements in the Method of and Means for Obtaining Copper
from Copper Ores.
We CHARLES ANTHONY BURGHARDT of 35 Fountain Street, Manchester,
in the County of Lancaster, Analytical Chemist, and GILBERT RIGG of
No. 1 Ellesmere Grove, Eccles, in the aforesaid county, Analytical Chemist,
do hereby declare the nature of this invention to be as follows:-
Our said invention relates to an improved mode of obtaining copper from copper
ores. In carrying our invention into effect we roast the ore to oxide in the usual
manner the roasting temperature being sufficiently high to transform the sulphate
of copper which may form during the roasting, into copper oxide.
The ore when thoroughly roasted is crushed into powder and placed in a tank.
fitted with a mechanical stirrer or agitator. We then make a concentrated
solution of either the normal carbonate of ammonium {(NH),CO₂} or the
sesquicarbonate of ammonium {(NH),CO, + 2 NHHCO) or the bicarbonate
of ammonium {NH,HCO,} or mixtures of these or a solution of ammonia gas in,
water and dissolve in this solution a sufficiency of zinc oxide to combine with the
liquor from 4000 to 5000 grains of zinc per gallon, where it is desired to obtain
the copper in a coherent form. The solution is now poured upon the crushed ore
in the tank and the agitator is set in motion to thoroughly mix the powder with
the solution. The liquid in the tank is kept covered with a layer of paraffin or
other mineral oil of high flashing point and low viscosity in order to prevent loss
of ammonia by volatilization. Under this treatment the oxide of copper is rapidly
dissolved out of the crushed ore. The agitation is then stopped and the solution
allowed to settle out all undissolved matter, the clear solution being then run into a
separate tank. We now proceed to recover the copper from the solution by placing
therein plates of metallic zinc or plates of metallic zinc and tin iu contact acting as
a couple. The copper is deposited upon the zinc as hard and bright metallic scales
and strips entirely free from oxide owing to the exclusion of air by the-supernatant
layer of paraffin or mineral oil. The solution might be warmed say to 40 degrees
Centigrade, or it might be cold. When the solution has been freed from copper it
may be returned upon the ore so as to extract a further proportion of copper and
this may he repeated several times until it is thought desirable to remove the excess
of zinc which accumulates in the solution with each successive recovery. To effect
this, the solution may be run into depositing tanks and the amount of zinc reduced
to 4000 or 5000 grains per gallon, after which the solution is again fit for service.
During the several uses and treatments of the solution its surface should be kept
covered with a skin of mineral oil as already said to prevent loss of ammonia.
Dated the and dama1008

page_text: COMPLETE SPECIFICATION.
Improvements in the Method of and Means for Obtaining Copper
from Copper Ores.
We Dr. CHARLES ANTHONY BURGHARDT of 35 Fountain Street, Manchester,
in the County of Lancaster, Analytical Chemist and Professor of Mineralogy in
the Victoria University, and GILBERT RIGG of No. 1 Ellesmere Grove, Eccles,
in the County of Lancaster, Analytical Chemist, do hereby declare the nature of
this invention and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement that is to say :-
Out said invention relates to an improved mode of obtaining copper from copper
ores. In carrying our invention into effect we roast the ore to oxide in the usual
manner the roasting temperature being sufficiently high to transform the sulphate
of copper which may form during the roasting, into copper oxide.
The ore when thoroughly roasted is crushed into powder and placed in a tank
fitted with a mechanical stirrer or agitator. We then make a concentrated
solution of either the normal carbonate of ammonium {(NH), CO,} or the
sesquicarbonate of ammonium {(NH),CO, +2 NH.HCO) or the bicarbonate
of ammonium {(NH¸HCO₂)} or mixtures of these or a solution of ammonia gas
in water and dissolve in this solution a sufficiency of zinc oxide to combine with
the liquor, from 4000 to 6000 grains of zinc per gallon, where it is desired to
obtain the copper in a coherent form. The solution is now poured upon the
crushed ore in the tank and the agitator is set in motion to thoroughly mix the
powder with the solution. The liquid in the tank is kept covered with a layer of
paraffin or other mineral oil of high flashing point and low viscosity in order to
prevent loss of ammonia by volatilization. Under this treatment the oxide of
copper is rapidly dissolved out of the crushed ore. The agitation is then stopped
and the solution allowed to settle out all undissolved matter, the clear solution
being then run into a separate tank. We now proceed to [recover the copper
from the solution by placing therein plates of metallic zinc or preferably
plates of metallic zinc and tin in contact acting as a couple. The copper
is deposited upon the zinc as hard and bright metallic scales and strips
entirely free from oxide, owing to the exclusion of air by the supernatant
layer of paraffin or mineral oil. The solution might be warmed say to
40 degrees Centigrade, or it might be cold. When the solution has been
freed from copper it may be returned upon the ore so as to extract a further
proportion of copper and this may be repeated several times until it is thought
desirable to remove the excess of zinc which accumulates in the solution with each
successive recovery. To effect this, the solution may be run into depositing tanks
and the amount of zinc reduced by electrolysis in the manner set forth in our
Specifications Nos. 19934 & 22732 both of 1895 until the zinc contained in the
solution is in the proportion of from 4000 to 5000 grains per gallon after which
the solution is again fit for service. During the several uses and treatments of the
solution its surface should be kept covered with a skin of mineral oil as already
said to prevent loss of ammonia.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed we declare that what
we claim is
(1.) The improved process for obtaining metallic copper from copper ores by
treating the roasted and ground ores with one of the hereinbefore described
solutions, having added thereto an amount of zinc equal to from 4000 to
to 5000 grains of zinc per gallon, and recovering the metallic copper from the

page_text: solution by immersed zinc or zinc and tin plates, the zinc being from time to time
recovered from the solution by electrolysis, all substantially as hereinbefore set
forth.
(2.) In carrying out the indicated process, preventing the loss of ammonia from
the solution by covering it with a layer of paraffin or other mineral oil as set
forth.
Dated the 21st day of August 1896.
For the Applicants,
E. K. DUTTON & Co.,
5 John Dalton Street, Manchester, Chartered Patent Agents.