AN IMPROVED MODE OF EXTRACTING SULPHUR FROM COMPOUNDS OF INDIA-RUBBER AND SULPHUR
Year: 1854

page_text: f
LETTERS PATENT to Alfred Vincent Newton. of the Office for Patents,
66. Chancery Lane, in the County of Middlesex, Mechanical Draughts-
man, for the Invention of "AN IMPROVED MODE OF EXTRACTING SULPHUR
FROM COMPOUNDS OF INDIA-RUBBER AND SULPHUR."-A communication.
PROVISIONAL SPECIFICATION left by the said Alfred Vincent Newton
at the Office of the Commissioners of Patents, with his Petition, on the
31st July 1854.
I. ALFRED VINCENT NEWTON, of the Office for Patents. 66. Chancery Lane,
in the County of Middlesex, Mechanical Draughtsman. do hereby declare the
nature of the said Invention for "AN IMPROVED MODE OF EXTRACTING SULPHUR
FROM COMPOUNDS OF INDIA-RUBBER AND SULPHUR" to be as follows:-
This Invention relates to the restoration of india-rubber to its natural state.
by depriving it of the sulphur which is incorporated in it by the process of
vulcanizing. For this purpose the india-rubber is reduced by any of the
known modes into as fine a state as possible, the finer the better, and then
treated with sulphuric ether. The mass is next placed in a solution of alcohol
and oil of turpentine, and boiled about two hours. Instead of treating the
comminuted india-rubber with sulphuric ether, as described, it may be first
[Price 8d.]

page_text: treated with the solution of alcohol and oil of turpentine, and during the boiling
the sulphuric ether may be applied.
Instead of oil of turpentine, chlorine or coal tar or other analogous material
may be used.
SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Alfred Vincent Newton in the Great Seal Patent Office
on the 31st January 1855.
TO ALL TO WHOM THESE PRESENTS SHALL COME, I, ALFRED
VINCENT NEWTON, of the Office for Patents, 66. Chancery Lane, in the County
of Middlesex. Mechanical Draughtsman, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria. by Her Leiters
Patent, bearing date the Thirty-first day of July, in the year of our Lord One
thousand eight hundred and fifty-four, in the eighteenth year of Her reign,
did, for Herself. Her heirs and successors. give and grant unto me, the
said Alfred Vincent Newton, Iler special license that I, the said Alfred
Vincent Newton, my executors, adininistrators, and assigns, or such others
as I. the said Alfred Vincent Newton. my executors.
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 "AN IMPROVED MODE OF EXTRACTING SULPHUR FROM COMPOUNDS
INDIA-RUBBER AND SULPHUR," being a communication from abroad, upon
the condition (amongst others) that 1, the said Alfred Vincent Newton, 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 Vincent Newton. 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 follow-
ing statement (that is to say):-
The object of this Invention is to extract the sulphur from india-rubber or

page_text: caoutchouc, whether combined or not with other like gums, such vegetable
gum or gums having previously undergone the vulcanizing or curing process
by the admixture therewith of sulphur, aided by artificial heat, whether com-
bined or not with other substances, and to restore the gum to its original or
native condition, or sufliciently near to that state to admit of its being again
used for the various purposes to which the gum can be applied.
The mode of procedure preferred by the Inventor is to take the vulcanized
gum and cut or reduce it into small pieces, the smaller the better, and steep it
in camphine from two to fourteen days. The length of time for steeping will
depend in a great measure upon the degree of vulcanization which the gum
has undergone. If vulcanized with a large proportion of sulphur, or at a high
or long continued heat, or with the salts of lead. or equivalent therefor, it will
be more refractory, and will require more time for the efficient action of the
camphine than if vulcanized with a small proportion of sulphur at a low heat.
The time required for this branch of the process will also much depend upon
the size to which the pieces are reduced, but whatever the circumstances of its
previous treatment it should be kept in the camphine until it becomes soft.
After this the gum is taken out of the camphine and put into a still of the
usual construction with fresh camphine in sufficient quantity to cover the gum.
and as the camphine evaporates during the distillatory process, a fresh supply is
to be added from time to time to keep the gum entirely immersed until the
sulphur is extracted: and with the camphine should also be put from fifteen
to twenty-five per cent. of sulphuric ether, and about five per cent. of alcohol.
to be gradually added as the camphine is added. The proportion of sulphuric
ether and alcohol used will be relative to the quantity of camphine employed
in this part of the process, the proportion of which latter substance should be
(by weight) about double that of the gum and the proportional quantity
of sulphuric ether will depend upon the proportional quantity of sulphur
contained in the gum.
The still being thus properly charged, a moderate degree of heat is applied."
say, from one hundred and fifty degrees to one hundred and sixty degrees
Fahrenheit. This must be continued until the gum assumes its original or
natural condition, although softer. which will take from three quarters of an
hour to two hours, depending upon the vulcanized condition of the gum, and
upon the proportional quantity of sulphuric ether employed: the greater the
quantity the more expeditious will be the process.
After the sulphur has been extracted and the gum restored to its natural
condition. (which is easily recognized by workmen experienced in the working

page_text: of india-rubber and allied gums. notwithstanding its soft state.) it is removed
from the still, put into flat pans, and dried by exposure io natural or a gentle
artificial heat.
When thus restored. the gum can be revulcanized or used for a variety of
purposes, like the native gum.
The sole object of using a still for this part of the process is to save the
sulphuric ether. alcohol, and camphine which distil over. and may be collected
in a condenser in the usual way: but if it be not desired io save these sub-
stances, the process can be conducted in any vessel or kettle. to which a
moderate degree of heat can be applied.
The object of using alcohol in the above process is to prevent the gum
when restored from being tacky, as it is termed, but when the tacky condition
of the gum is not objectionable the alcohol may be dispensed with: and as the
object of using alcohol is to prevent the gum from being tacky when restored.
any equivalent chemical agent. such as fusel oil, may be substituted, but
alcohol has been ascertained by experiment to be the best.
The camphine is the softening or dissolving agent which enables the ether
to reach or extract the sulphur present in the vulcanized gum. and therefore
any of the essential oils or other solvents of india-rubber and allied gums may
be substituted, but the use of camphine is preferred.
The office of the sulphuric ether is to extract the sulphur from the gum,
which it does by reason of its affinity therefor any other chemical agent having
equivalent properties, such as chloroform, natron. kali. or benzole, may ihere-
fore be substituted for the sulphuric ether: but with this as with the other
agents, those first specified are preferred, on account of efficiency and economy.
If, for instance, chloroform be substituted for sulphuric ether. the proportional
quantity of the camphine or dissolving agent may be greatly reduced, and the
alcohol may be entirely omitted: but the use of this substitute or equivalent
.is more dangerous and expensive.
Instead of first steeping the vulcanized gum in camphine, or an equivalent
dissolving agent, it may he first steeped in sulphuric ether. or its equivalent.
and then put in the still or other heating vessel with camphine. and a small
quantity of sulphuric ether and alcohol, if desired. Or. instead of first steeping
in camphine or sulphuric ether. this part of the process may be dispensed with.
and the whole subjected at once to the several agents simultaneously: but
experiment has proved the mode of procedure first described to be the best.
Having thus set forth the nature of the Invention of "An Improved Mode
of Extracting Sulphur from Compounds of India-rubber and Sulphur." as

page_text: communicated to me by my foreign correspondent. and explained the means
for carrying the same into effect. I wish it to be understood that under the
above in part recited Letters Patent I do not limit myself to the use of the
substances specified, nor to the order specified in the mode of procedure, as
these may be greatly changed without departing from the nature of the Inven-
tion; but what I claim is, the process, substantially as herein described, of
devulcanizing india-rubber compounds.
In witness whereof. 1. the said Alfred Vincent Newton, have hereunto
set my hand and seal, the Thirty-first day of January, in the year of
our Lord One thousand eight hundred and fifty-five.
Witness,
J. W. MOFFATT,
66, Chancery Lane.
A. V. NEWTON. (L.S.)