IMPROVEMENTS IN THE MANUFACTURE OF CHROMATES AND BICHROMATES." PROVISIONAL SPECIFICATION
Year: 1864

page_text: LETTERS PATENT to Benedict Margulies, of Trieste, in the Empire of
Austria, but now residing at St. Helens, in the County of Lancaster,
Chemist, and John Knowles Leather, of the same Place, Manufacturing
Chemist, for the Invention of "IMPROVEMENTS IN THE MANUFACTURE OF
CHROMATES AND BICHROMATES."
PROVISIONAL SPECIFICATION left by the said Benedict Margulies and
John Knowles Leather at the Office of the Commissioners of Patents,
with their Petition, on the 6th October 1864.
We, BENEDICT MARGULIES, of Trieste, in the Empire of Austria, but now
residing at St. Helens, in the County of Lancaster, Chemist, and JOHN
KNOWLES LEATHER, of the same Place, Manufacturing Chemist, do hereby
declare the nature of the said Invention for "IMPROVEMENTS IN THE MANU-
FACTURE OF CHROMATES AND BICHROMATES," to be as follows:-
The object, of this Invention is to manufacture chromates and bichromates
in a more economical manner than is now commonly practised. To this end
we prepare a mixture of lime, or of bydrate of lime, or of other alkaline earths,
and of chrome ore, or of oxide of chromium (or of one or more of the impure
compounds of chromium) with or without one or more of the salts of soda or

page_text: potash, and with or without manganese or other oxygen-bearing material, and
with or without silica or other difficultly fusible material (the use of which is
to prevent the mixture from fluxing when exposed to a strong heat), and we
form the same into blocks, which we submit to the heat of a furnace until the
chrome ore or oxide or other compound of chromium is decomposed. The
blocks we prefer to make in the shape of the frustum of a cone. It is not
necessary that any of the substances aforesaid be pure, and they may be used
_in_equal_parts_by_weight,_or_in_various_proportions._From_amongst the
substances aforesaid we prefer to use equal parts by weight of bydrate of lime
and sulphate of potash and chrome ore reduced to a finely divided state, and
after well mixing them in any convenient manner to add water, and by kneading
to bring the mixture to the consistency of clay, after which we mould it into
conical blocks. The blocks thus formed we expose, whether in a dry or a moist
state, to the heat of a furnace or oven, but by preference we use the hearth
of a reverberatory furnace, and subject the blocks to a heat gradually
increasing from a low heat to a full red heat, or even to a white heat, being
careful not to allow the heat to increase so as to flux them, as in that case the
mass would be very difficult to lixiviate. The blocks are to remain in the
furnace until the chrome ore, oxide of chromium or other compound of
chromium has been- either wholly or partially decomposed. The blocks are
then raked out and placed in any convenient vessel and the soluble compounds
of chromium dissolved out either with water or with a solution of one or more
of the salts of soda or potash, and the liquor is treated by any of the usual
methods for the manufacture of chromates and bichromates therefrom. If the
mixture after lixiviation contains any undecomposed chromium, it is to be
formed again into blocks, either in the same state as it is removed from the
lixiviating vessels, or after the addition of one or more of the materials afore-
said, and again exposed to the heat of a furnace or oven as before. We then
extract the soluble compounds of chromium which may have been formed
within the furnace by lixiviation in the manner already mentioned...
.5.
The Invention is also applicable to the production of chromates and bichro-
mates from any undecomposed chrome ore, oxide;of chromium, or impure salts
of chromium contained in the residuary matter which remains after lixiviation:
of the chrome charges operated on in the furnace by the ordinary method.
Such residuary matter is to be treated in precisely the same way as that last

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent, filed
by the said Benedict Margulies and John Knowles Leather in the Great
Seal Patent Office on the 6th April 1865.
TO ALL TO WHOM THESE PRESENTS SHALL COME, we, BENEDICT
MARGULIES, of Trieste, in the Empire of Austria, but now residing at Saint
Helens, in the County of Lancaster, Chemist, and JOHN KNOWLES LEATHER, of
the same Place, Manufacturing Chemist, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Letters
Patent, bearing date the Sixth day of October, in the year of our Lord One-
thousand eight hundred and sixty-four, in the twenty-eighth year of Her
reign, did, for Herself, Her heirs and successors, give and grant unto us,
the said Benedict Margulies and John Knowles Leather, Her special license
that we, the said Benedict Margulies and John Knowles Leather, our
executors, administrators, and assigns, or such others as we, the said.
Benedict Margulies and John Knowles Leather, our executors, adminis-
trators, 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 CHROMATES AND
BICHROMATES," upon the condition (amongst others) that we, the said Benedict
Margulies and John. Knowles Leather, by an instrument in writing under
our hands and seals, or under the hand and seal of one of us, should par-,
ticularly 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 imme-.
diately after the date of the said Letters Patent.
NOW KNOW YE, that I, the said John Knowles Leather, on behalf of
myself and of the said Benedict Margulies, do hereby declare the nature of
our 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 to manufacture chromates and bichromates
in a more economical manner than is now commonly practised. Hitherto the
prevailing mode of carrying on the manufacture of chromates and bichromates,
has been to spread the charge (composed chiefly of lime and of..one or more
of the salts of soda or potash and chrome ore, or its equivalent) on the hearth.
of a furnace, and thus to expose it to the action of heat for the purpose of

page_text: decomposing the materials, forming the, charge, and effecting their desired
conversion. In order, however, to effect an important economy in the manu-
facture, we prepare a mixture of lime or of hydrate of lime, and of chrome
ore, or of oxide of chromium, or of one or more of the impure compounds of
chromium with or without one or more of the salts of soda or potash, and with or
without manganese or other oxygen-bearing material, and with or without silica.
or other difficultly fusible material (the use of which is to prevent the mixture
from fluxing-when-exposed-to-a-strong-heat). This mixture, either in a dry
state or after the addition of water, we mould into blocks, which we submit to
the heat of a furnace until the chrome ore or oxide, or other compound, of
chromium is decomposed; the blocks may be of any. size or shape, but: we
prefer to make them in the shape of the frustum of a.cone.measuring about
eighteen inches high, eight inches in diameter at top, and. nine inches. at; the
base. It is not necessary that any of the substances aforesaid: be pure, and
they may be used in equal parts by weight or in various proportions. From
amongst the substances aforesaid, we prefer to use equal parts by weight of
hydrate of lime and sulphate of potash and chrome ore reduced to a finely
divided state, and after well mixing them in any convenient manner to add
water, and by kneading to bring the mixture to the consistency of clay, after
which we mould it into conical blocks. The blocks thus formed we expose
whether in a dry or a moist state to the heat of a furnace or oven, but by
preference we use the hearth of a reverberatory furnace, and subject the blocks
to a heat gradually increasing from a low heat to a full red heat, or even to.a.
white beat, being careful not to allow the heat to increase so as to flux them,
as in that case the mass would be very difficult to lixiviate. The blocks.are
to remain in the furnace until the chrome or oxide of chromium or other
compound of this substance has been either wholly or partially decomposed,
the blocks are then to be raked out and placed in any convenient vessel, where
the soluble compounds of chromium are dissolved out either by the action of
water or a solution of one or more of the salts of soda or potash. The liquor
which contains the chrome.is then to be treated by any of the usual methods
for the manufacture of chromates and bichromates therefrom. If the mixture
after lixiviation contains any undecomposed chromium or its oxide, it is to be
formed again into blocks either in the same state in which it is removed from
the lixiviating vessels, or after the addition of one or more of the materials
aforesaid, and again exposed to the heat of a furnace or oven, as heretofore
described. We then extract by lixiviation the soluble compounds containing
the chromium, which have been formed within the furnace in the manner
already mentioned.

page_text: The Invention is also applicable to the production of chromates and bichro-
mates from any undecomposed chrome ore or oxide of the same, which may be
in mixture in the residuary matter after lixiviation of the chrome charges
operated on in the furnace by the ordinary method. Such residuary matter is
to be treated in precisely the same way as that last mentioned.
Having now set forth the nature of our Invention of "Improvements in the
Manufacture of Chromates and Bichromates," and explained the manner of
carrying the same into effect, we wish it to be understood that under the above
in part recited Letters Patent we claim, preparing the charge and submitting
it to the action of the heat of the decomposing furnace in a compact mass, in
the manner and for the purpose above described.
In witness whereof, I, the said John Knowles Leather, hath hereunto
set my hand and seal, the Fourth day of April, in the year of our
Lord One thousand eight hundred and sixty-five.
JNO. KNOWLES LEATHER. (L.s.)