IMPROVEMENTS IN THE MANUFACTURE OF SULPHURIC ACID WHEN ROASTING COPPER ORES, AND ALSO WHEN BURNING SULPHUR OR IRON PYRITES.
Year: 1854

page_text: LETTERS PATENT to Alfred Trueman, of Swansea, in the County of
Glamorgan, for the Invention of "IMPROVEMENTS IN THE MANUFACTURE OF
SULPHURIC ACID WHEN ROASTING COPPER ORES, AND ALSO WHEN BURNING
SULPHUR OR IRON PYRITES.".
Sealed the 17th August 1854, and dated the 2nd May 1854.
PROVISIONAL SPECIFICATION left by the said Alfred Trueman at the
Office of the Commissioners of Patents, with his Petition, on the 2nd
May 1854.
I, ALFRED TRUEMAN, of Swansea, in the County of Glamorgan, do hereby
declare the nature of the Invention for "IMPROVEMENTS IN THE MANUFACTURE
OF SULPHURIC ACID WHEN ROASTING COPPER ORES, AND ALSO WHEN BURNING SULPHUR
OR IRON PYRITES," to be as follows:-
This Invention consists in passing the sulphurous acid resulting from the
roasting of copper ores mixed with oxygen, atmospheric air, or any suitable
matter containing oxygenincontactwith heated platinum, oxide of iron, or other
substance having in a heated state the property of causing oxygen to combine
with sulphurous acid, so as to form sulphuric acid. And the Invention also
consists in the employment of platinum, oxide of iron, or other matter (having
in a heated state the property of causing the combination of sulphurous acid
Price 8d.1

page_text: and oxygen) diffused in the pores of pumice stone, burnt clay, or other similar
substance, for the purpose of converting a mixture of sulphurous acid and
oxygen, atmospheric air, or other suitable matter containing oxygen, into
sulphuric acid,
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Alfred Trueman in the Great Seal Patent Office on the
1st November 1854.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALFRED
TRUEMAN, of Swansea, in the County of Glamorgan, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Second day of May, in the year of our Lord
One thousand eight hundred and fifty-four, in the seventeenth year of
Her reign, did, for Herself, Her heirs and successors, give and grant unto
me, the said Alfred Trueman, Her special licence that I, the said Alfred
Trueman, my executors, administrators, and assigns, or such others as I, the
said Alfred Trueman, 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 MANUFACTURE OF SULPHURIC ACID WHEN ROASTING COPPER ORES, AND
ALSO WHEN BURNING SULPHUR OR IRON PYRITES," upon the condition (amongst
others) that I, the said Alfred Trueman, 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 Alfred Trueman, do hereby declare
the nature of the said Invention, and in-what-manner-the-same-is-to-be
performed, to be particularly described and ascertained in and by the following
statement thereof (that is to say):-
This Invention consists in passing the sulphurous acid resulting from, the
roasting of copper ores, mixed with oxygen, atmospheric air, or any suitable
matter containing oxygen in contact with heated platinum, oxide of iron, or

page_text: other substance, having in a heated state the property of causing oxygen to
combine with sulphurous acid, so as to form sulphuric acid. And the Invention
also consists in the employment of platinum, oxide of iron, or other matter
(having in a heated state the property of causing the combination of sulphurous
acid and oxygen) diffused in the pores of pumice stone, burnt clay, or other
similar substance, for the purpose of converting a mixture of sulphurous acid-
and oxygen, atmospheric air, or other suitable matter containing oxygen, into
sulphuric acid.
.
Having thus stated the nature of my said Invention, I will proceed to
describe the manner of performing the same.
The first part of my Invention relates, as above stated, to the converting of
the sulphurous acid gas resulting from the roasting of copper ores into sul-
phuric acid; and I would state that I am aware that it is not new to convert
the sulphurous acid derived from the roasting of copper ores into sulphuric
acid, but the means heretofore resorted to for such purpose are different from
those employed by me; and I am also aware that it has before been proposed
to use heated platinum and oxides for converting sulphurous acid gas derived
from the burning of sulphur into sulphuric acid, and I mention these matters
in order to state that I do not claim either of such processes; and I would
further state, that the first part of my Invention consists of applying heated
platinum or heated oxides in combination with the process of roasting copper
ores, so that the sulphurous acid gas evolved in sach process may, in place of
passing into the atmosphere, be converted into sulphuric acid, by being, toge-
ther with oxygen, brought into contact with heated platinum, or with heated
oxides; and I believe the most suitable oxides are oxides of iron, oxides of
copper, oxides of chromium, and oxides of manganese. And in carrying out
this part of my Invention, if platinum be used it may be employed in any
suitable form; but I believe the most convenient is that of rolling platinum
wire loosely into balls, and placing them in earthenware tubes or passages,
suitably arranged to admit of their being with their contents readily kept at
a red heat; and when oxides are used they are broken into small lumps and
similarly used. Through these heated tubes, the sulphurous acid gas as it
comes from the roasting copper ores is (together with oxygen from atmospheric
air or otherwise) caused to pass in such manner as to be brought well in
contact with the beated matter, whereby sulphuric acid will be formed, which
is to be condensed by descending into or coming in contact with water; for
which purpose I use numerous small pipes in connection with the heated tubes
or passages, the ends of which small pipes descend a short distance under water,

page_text: in a vessel, the air from which is continuously withdrawn by any suitable appa-
ratus, by which quantities of atmospheric air will at the same time be drawn,
through the tubes or passages, and will combine with the sulphurous acid gas,
and present oxygen for the process, which I believe to be the best means of
getting the requisite supply of oxygen, though, if preferred, other means of
supplying oxygen may be resorted to. Or, in place of withdrawing air from
à closed vessel, the sulphurous acid gas, as it is obtained when roasting copper
ores, may, by a fan or other suitable apparatus, be driven, together with oxygen,
through the tubes or passages, and in contact with the heated platinum or
the heated oxides, and thence in contact with water to be condensed. The
sulphuric acid thus obtained is then to be treated as heretofore, and as is well
understood. I would here state, that although I have above described the use
of platinum and oxides arranged with apparatus for heating the same in com-
bination with ovens or furnaces used for roasting copper ores, I however prefer
to employ those matters in the manner which I will now proceed to describe,
and which constitutes the second part of my Invention, which consists of
employing platinum or oxides combined with porous matters; and the best
means I am acquainted with for carrying this into practice is to employ these
matters in a state of solution, so as to facilitate their combination with porous
matters, such as pumice stone, burned clay, or others admitting of being sub-
jected to a red heat. For this purpose I usca solution of chloride of platinum,
with which I impregnate, by preference, pumice stone, and then subject the
same to a high heat to drive off the chlorine; after which I employ the pumice
stone or porous matter combined with platinum, in pipes or passages heated
to a red heat, and I cause sulphurous acid gas, whether obtained from roasting
copper or other ores, or by burning sulphur or pyrites to be passed together
with oxygen in contact with such heated matters, and I then cause the pro-
ducts to be brought in contact with and condensed in water. Or, when using
oxides, such as herein-before mentioned, I cause them to be incorporated or
combined with porous matters, preferring pumice stone; and I use for such
purpose a solution of either of such oxides, I believe a sulphate solution
is as convenient as any, and having impregnated the porous-substance there-
with I subject-the-same to a high heat to drive off the sulphuric acid. I then
use the compound of porous matter and oxide in any suitable pipes, passages,
or apparatus, heated to a red heat, so that sulphurous acid gas derived from
any source may be brought together with oxygen in contact therewith, and the
product condensed in water.
Having thus described the nature of my said Invention, and the manner of

page_text: performing the same, I would have it understood that I do not confine myself
to the details herein described; but what I claim is,-
First, the application in suitable apparatus of platinum or oxides in' com-
bination with ovens or furnaces wherein copper ores are roasted, in order to
convert the sulphurous acid gas derived from such process of roasting copper
ores into sulphuric acid.
And secondly, I claim the application of platinum, and also of oxides
combined with pumice stone or porous matters, in the manufacture of
sulphuric acid.
In witness whereof, I, the said Alfred Trueman, have hereunto set my
hand and seal, this Twenty-eighth day of October, in the year of our
Lord One thousand eight hundred and fifty-four.
Witness,
S. CARPMAEL.
ALFRED TRUEMAN. (L.S.)