IMPROVEMENTS IN THE SEPARATION OF COPPER FROM ORES
Year: 1869

page_text: LETTERS PATENT to Peter Spence, of Newton Heath, Manchester, in
the County of Lancaster, Manufacturing Chemist, for the Invention
of "IMPROVEMENTS IN THE SEPARATION OF COPPER FROM ORES."
Sealed the 1st March 1870 and dated the 4th September 1869.

page_text: "
solution sulphide of ammonium obtained from "alkali waste com-
bined with chloride or other salt of ammonium; this precipitates the
copper as a sulphide and the liquor becomes chloride of ammonium,
which may again be used as above described.
By another plan I precipitate the copper by sulphuretted hydrogen
obtained from "soda waste," or the spent lime of gas works, by acting
upon it with an acid. The spent liquor will then be acid and may be
used again by being more or less strengthened.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Peter Spence in the Great Seal Patent Office on
the 4th March 1870.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, PETER
SPENCE, of Newton Heath, Manchester, in the County of Lancaster,
Manufacturing Chemist, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Fourth day of September, in the year of
our Lord One thousand eight hundred and sixty-nine, in the thirty-third
year of Her reign, did for Herself, Her heirs and successors, give and
grant unto me, the said Peter Spence, Her special license that I, the
said Peter Spence, my executors, administrators, and assigns, or such
others as I, the said Peter Spence, my executors, administrators, and
assigns, should at any time agree with, and no others, from time to
. time and. at, all times thereafter during the term therein expressed,
should and lawfully might make, use, exercise, and vend, within the
United Kingdom of Great Britain and Ireland, the Channel Islands, and
Isle of Man, an Invention for "IMPROVEMENTS IN THE SEPARATION OF COPPER
. PROM ORES," upon the condition, amongst others, that I. the said Peter
Spence, by an instrument in writing under my hand and seal, should
particularly describe and ascertain the nature of the said Invention,
and, in what manner the same was to be performed, and cause the
same to: be: filed in the Great Seal Patent Office within six calendar
months next and immediately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said Peter Spence, do hereby declare
and in what manner the same is to

page_text: following statement, that is to say:-
My Invention relates to the separation of copper from ores by the
"wet process," and in obtaining it as a sulphide to be subsequently
reduced to the metallic state by any known process.
To effect this I propose to use sulphide of ammonium or sulphuretted
hydrogen obtained by certain means..
In carrying out my Invention I take the solution as now obtained in
extracting copper from ores by the wet process, which solution is a
chloride of copper containing iron in variable proportions, and generally.
containing free hydrochloric acid. I place this liquor in large open
vats, and in another vessel of cast iron fitted with a revolving stirrer I
place a considerable quantity (say until it is one-third full) of the vat
waste of the alkali manufacture, which waste I prefer to be in a fresh
condition; or I use the same quantity of the spent lime from the gas
purifiers; to this I add a solution (containing, say, one-fourth the weight
of the vat waste or spent lime) of sulphate of ammonia or chloride of
ammonium. The vessel being closed I blow into the solution and
material a jet of steam, say from 20 lbs. to 30 lbs. pressure. A pipe
leading from the said vessel or still is carried into the vat containing
the solution of copper and iron. Sulphate of ammonium distils over
into the metallic solution, sulphide of copper is precipitated, and the
ammonia combines with the liberated hydrochloric acid. The process
is continued until all the copper is thrown down, which point is at once
observed by sulphuretted hydrogen being evolved, and the process is
stopped, for if continued the ammonia would now neutralize the free
acid, and the iron would then be precipitated. The sulphide of copper
is now allowed to settle, and the supernatant liquor being drawn off
water is added to wash out the acid solution of chloride of ammonium
and iron, which is used with a new charge of vat waste or spent lime in.
the. still, and so the process is carried on continuously with the same
ammonia; but as there is a small loss of ammonia from its being
impracticable to completely distil off every charge, and also from
imperfect washing of the sulphide of copper, a quantity of ammoniacal
water of gas works may be used in the still to make up the deficiency.
The sulphide of copper, nearly pure, or with a mere trace of sulphide of
iron, is dried and smelted into copper by any of the usual methods, or

page_text: it may to a large extent be converted into sulphate of copper by being
heated nearly to redness in a furnace and then dissolved in water. The
insoluble portion left may be smelted as before mentioned.
In carrying out my Invention by another method I add gradually
to the alkali waste or spent gas lime in a close vessel hydrochloric acid,
passing the sulphuretted hydrogen obtained thereby into vats or vessels
containing the metallic solution, and sulphide of copper is precipitated.
I continue this operation until all is thrown down, and the residual
liquor being now strongly acid is used for the next charge, being
again added gradually to the spent lime or alkali waste, and ordinary
hydrochloric acid is used to supply the deficiency. The sulphide of
copper is in this case also nearly pure, and may be smelted into copper,
as before mentioned.
Having thus described and ascertained the nature of my said In-
vention, and the manner in which the same is to be performed, I desire
it to be understood that I claim as secured to me under the above in
part recited Letters Patent, the manufacture of copper in the wet mode
of extraction from ores by precipitating the copper as sulphide by means
of sulphide of ammonium obtained by distillation from alkali wate or
spent gas lime mixed with solutions of salts or compounds of ammonium,
whether such ammonia compounds be produced during the operation of
the said process, or otherwise obtained; also by sulphuretted hydrogen
obtained by acting on alkali waste or spent gas lime with hydrochloric
acid from aforesaid metallic solutions, or from other sources, substan-
tially as described.
In witness whereof, I, the said Peter Spence, have hereunto set my
hand and seal, this Third day of March, in the year of our Lord
One thousand eight hundred and seventy.
PETER SPENCE. (L.S.)