TUPROVEMENT IN MUR PURIFICATION OR COAL GAS ”
Year: 1873

page_text: LETTERS PATENT to Henry Young Darracott Scott, of Ealing, in the
County of Middlesex, Major General, C.B., for the Invention of
"TUPROVEMENT IN MUR PURIFICATION OR COAL GAS ”
PROVISIONAL SPECIFICATION left by the said Henry Young Darracott
Scott at the Office of the Commissioners of Patents, with 'his
Petition, on the 16th January 1873.
I, HENRY YOUNG DARRACOTT SCOTT, of Ealing, in the County of
Middlesex, Major General, C.B., do hereby declare the nature of the
said Invention for "IMPROVEMENts in the PurifiICATION OF COAL Gas," to be
as follows: :_
The object of this Invention is the removal of sulphur from coal gas
in a cheap and efficient manner.
In carrying out my Invention I take.oxide of iron and having heated
it to redness in a suitable chamber or conduit, I pass the the gas to
be purified over it. The beated iron oxide will abstract the sulphur of the .:

page_text: sulphur compounds present, and leave the gas comparatively pure from
such contaminations.
The oxide of iron may be purified and be re-used for the purification of
a fresh charge of gas.
The advantage of heated oxide of iron over lime for the above purpose,
consists in this property of ready revivification and in the greater facility
with which it is decomposed by sulphur compounds. Lime may
however be used in conjunction with the iron oxide for this mode of
purification of gas, and I sometimes find it convenient, whether these
substances are used conjointly or singly, to subject the gas after it has
been passed through the heated substance as well as before this treat-
ment to the ordinary processes of removing sulphuretted hydrogen from
coal gas.
Other metallic oxides besides iron and other alkaline carths besides
lime may be used, but they are more costly than these substances and
their use is not attended with any equivalent advantage.
SPECIFICATION in pursuance of the conditions of the Letters Patent,
filed by the said Henry Young Darracott Scott in the Great Seal
Patent Office on the 15th July 1873.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, HENRY
YOUNG DARRACOTT SCOTT, of Ealing, in the County of Middlesex,
Major General, C.B., send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her
Letters Patent, bearing date the Sixteenth day of January, in the
year of our Lord One thousand eight hundred and seventy-three, in
the thirty-sixth year of Her reign, did, for Herself, Her heirs and
successors, give and grant unto me, the said Henry Young Darracott
Scott, Her special licence that I, the said Henry Young Darracott Scott,
my executors, administrators, and assigns, or such others as I, the said
Henry Young Darracott Scott, 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

page_text: Kingdom of Great Britain and Ireland, the Channel Islands, and Isle
of Man, an Invention for "IMPROVEMENTS IN THE PURIFICATION OF COAL GAS,"
upon the condition (amongst others) that I, the said Henry Young
Darracott Scott, my executors or administrators, by an instrument in
writing under my, or their, or one of their hands and seals, should parti-
cularly 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 Henry Young Darracott Scott, do
hereby declare the nature of my said 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) :-
The object of this Invention is the removal of sulphur from coal gas
in a cheap and efficient manner.
In carrying out my Invention I take oxide of iron, and having heated
it to redness in a suitable chamber or conduit, I pass the gas as it comes
from the condenser over the heated oxide of iron in the improved
purifier.
I find that the most suitable temperatures for heating the oxide of
iron for the purpose, are those varying between a redness just visible in
the dark and a low red heat, and that the most convenient form in which
the oxide can be used is in small pieces, or in a coarse granulated
state. The object I have in view is to promote the ready permeation of
the mass of oxide of iron by the gas, and the exposure of a large surfaco
of the purifying material, so that the whole body of gas may be
thoroughly acted upon. The chamber or conduit containing the oxido
may be constructed in the form of an iron retort, and two, three, or
more of these retorts may be arranged like a bench of ordinary gas
retorts, but connected together by suitable pipes, so that the gas may
pass through them all in succession. These purifying retorts or
chambers may be heated in any convenient manner by means of a
furnace, the flames of which will play around the chambers containing
the oxide of iron which may be arranged either upon shelves or simply
be placed loosely in the purifying chambers.
The heated iron oxide will act on the sulphur of the sulphur com-
pounds contained in the gas, and will cause their decomposition, the

page_text: .
sulphur being made to combine with the oxide of iron, thus leaving the
gas comparatively pure from such contaminations.
The oxide of iron may be revivified and be re-used for the purification
of a fresh charge of gas.
The advantage of heated oxide of iron over lime for the above purpose,
consists in this property of ready revivification, and in the greater facility
with which it is decomposed by sulphur compounds. Lime may
however be used in conjunction with the iron oxide for this mode of
purification of gas, and I sometimes find it convenient (whether these
substances are used conjointly or singly) to subject the gas (after it has
been passed through the heated substance as well as before this treat-
ment) to the ordinary processes of removing sulphuretted hydrogen from
coal gas.
Other metallic oxides besides iron, and other alkaline earths besides
lime may be used, but they are more costly than these substances and
their use is not attended with any equivalent advantage.
Having now described my Invention of " Improvements in the Purifi-
cation of Coal Gas," and having explained the manner of carrying the
same into effect, I claim as the Invention secured to me by Letters
Patent as aforesaid purifying coal gas by passing it over oxide of iron
hcated to redness as herein set forth.
In witness whereof, I, the said Henry Young Darracott Scott, have
hereunto set my hand and seal, the Fourteenth day of July, in
the year of our Lord One thousand eight hundred and seventy-
threc.
HENRY Y. D. SCOTT (L.S.)