IMPROVE- MENTS IN THE MANUFACTURE OF CARBONATES OF SODA AND POTASH
Year: 1841

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, WILLIAM
THOMPSON CLOUGH, of Saint Helens, in the County of Lancaster, Alkali
Manufacturer, send greeting.
WHEREAS Her present most Excellent Majesty Queen Victoria, by Her
Letters Patent under the Great Seal of Great Britain, bearing date at West-
minster, the Seventeenth day of March, in the fourth year of Her reign,
did, for Herself, Her heirs and successors, give and grant unto me, the said
William Thompson Clough, Her especial licence, full power, sole privilege
and authority, that I, the said William Thompson Clough, my exors, adñiors,
and assigns, or such others as I, the said William Thompson Clough, my
exors, adiñors, or assigns, should at any time agree with, and no others, from
time to time and at all times during the term of years therein expressed,
should and lawfully might make, use, exercise, and vend, within England,
Wales, and the Town of Berwick-upon-Tweed, my Invention of "IMPROVE-
MENTS IN THE MANUFACTURE OF CARBONATES OF SODA AND POTASH;" in which
said Letters Patent is contained a proviso, that I, the said William Thomp-
son Clough, shall 'cause a particular description of the nature of my said
Invention, and in what manner the same is to be performed, to be inrolled
in Her said Majesty's High Court of Chancery within six calendar months
next and immediately after the date of the said in part recited Letters Patent,
as in and by the same, reference being thereunto had, will more fully and at
large appear.

page_text: NOW KNOW YE, that in compliance with the said proviso, I, the said
William Thompson Clough, do hereby declare that my Invention relates to a
mode of obtaining soda crystals more advantageously; and the Invention also
relates to the preparing what are called dry carbonates of soda and potash of
commerce, in order to render such carbonates more useful when applied to
beleaching purposes, and such improvements consist of means of employing
silica, as hereafter explained.
And in order that my Invention may be most fully understood and readily
carried into effect, I will proceed to describe the means pursued by me, first
remarking that I prefer to employ similar sand to that used by flint glass
manufacturers, though I do not confine myself thereto, as other silica may be
used.
In carrying out my Invention, I throw into the furnace a quantity of silica
with the alkali (soda or potass) in the process of manufacture, in such proportion
as to be sufficient to saturate the caustic alkali which they may contain, thus
converting it into silicate of potassa or soda, as the case may be; and I apply
silica either to the alkaline liquor in the "boiling-down" furnace, where it is
reduced to a salt previous to drying and finishing; or, by preference, when for
soda ash or potash of commerce, I mix with a shovel or other instrument the
silica with the salts from the boiling-down furnace, and throw the combined
materials into the finishing or carbonating furnace. 1 mix from ten to fifteen
per cent.. of silica to the salts drawn out of the boiling-down furnaces, and then
finish the salts in the ordinary manner; in fact, the whole process of making
the salts is. pursued as heretofore, excepting the using of silica, by which the
results obtained will be materially benefited. In the
process of
crystallization
of carbonate of soda the resulting "mother salts" from the residual liquor
retain the whole of the silicate of soda, whilst the larger part of the carbonate
has separated in crystals nearly pure and colorless, and I find that a larger
product or " crop "of crystals is obtained, and the value of the mother salt
improved.
I would remark, that although I have been particular in thus describing the
means pursued by me in combining silica in the manufacture and preparation
of the crystals of soda, and dry carbonate of potash and soda of commerce, I
do not confine myself thereto, as other means may be resorted to for applying.
silica in the manufacture of the carbonates of soda and potash, the object being
to neutralize the causticity of those alkalies in the progress of manufacture, and
thus to obtain more useful products by compounding silica therewith. I how-
ever believe that the above-described means are the best for carrying out my

page_text: Invention, particularly when crystals are required, and the dry ash or carbonate,
of soda of commerce are both to be made;. but when only the dry ash or cár-
bonate of soda of commerce be required for the purposes of the bleacher, a
very similar product to that obtained by me from the mother waters, as above
described, may be produced by simply combining a quantity of silicate of soda
or potash with the carbonate of soda or of potash of commerce in such pro-
portion that the mixture shall contain twenty per cent. of silicate of soda or
potash; and such mixing may be performed in any convenient manner, either
in the state of powder and mix them mechanically, or when the alkali is in
a state of solution in water. I do not, however, confine myself to the
above per-centage, though I believe twenty per cent. will be the most
beneficial:
I would remark, that for salts of potash I proceed after the same methods as
are above described, but I reduce the per-centage from ten to seven. I would
state, that a larger quantity of silica than what has been above mentioned will
not materially prejudice the working, and the use of less silica than is required
to neutralize the causticity will produce only proportionable benefit in the
process of manufacture. And I wish it to be understood that I am aware
that it is not new to produce silicate of soda or potash by combining silica with
carbonate or caustic soda or potash, and I make no claim thereto; my Inven-
tion having for its object,―
First, the use of silica to neutralize the causticity of the salts of soda and
potash, and thus to facilitate the obtaining crystals of carbonate of soda.
And, secondly, to obtain carbonate of soda or potash in combination with
silicate of soda or potash, by which means the properties of the carbonate of
soda or of potash will be found to be materially enhanced.
In witness whereof, I, the said William Thompson Clough, have hereunto
set my hand and affixed my seal, this Fifteenth day of September,
in the year of our Lord One thousand eight hundred and forty-one.

page_text: AND BE IT REMEMBERED, that on the Fifteenth day of September, in
the year of our Lord 1841, the aforesaid William Thompson Clough came
before our said Lady the Queen in Her Chancery, and acknowledged the
Specification aforesaid, and all and every thing therein contained and specified,
in form above written. And also the Specification aforesaid was stamped
according to the tenor of the Statute.made for that purpose..
Inrolled the Seventeenth day of September, in the year of our Lord One
thousand eight hundred and forty-one.