CERTAIN IMPROVEMENTS IN THE MANUFACTURE OF SODA, MURIATIC AND NITRIC ACIDS
Year: 1850

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, I, PETER
ARMAND Lecomte de FONTAINEMOREAU, of South Street, Finsbury, London,
in the County of Middlesex, send greeting.
WHEREAS Her most Excellent Majesty Queen Victoria, by Her Royal
Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Eleventh day of June,
Eighteen hundred and fifty, in the thirteenth year of. Her reign, did give and
grant unto me, the said Peter. Armand Lecomte de Fontainemoreau, my
exors, adiñors, and assigns, Her especial licence, full power, sole privilege
and authority, that I, the said Peter Armand Lecomte de Fontainemoreau,
my exors, admors, and assigns, or such others as I, the said Peter Armand
Lecomte de Fontainemoreau, my exors, adññiors, or assigns, should at any
time agree with, and no others, from time to time and at all times hereafter,
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, and in the Islands of Guernsey, Jersey, Alderney, Sark, and
Man, and in all Your Majesty's Colonies and Plantations abroad, the Invention
of "CERTAIN IMPROVEMENTS IN THE MANUFACTURE OF SODA, MURIATIC AND
NITRIC ACIDS," communicated to me by a Foreigner residing abroad; in
which said Letters Patent there is contained a proviso requiring that I, the
said Peter Armand Lecomte de Fontainemoreau, should particularly describe
and ascertain the nature of the said Invention, and in what manner the same
is to be performed, by an instrument in writing under my hand and seal, and
cause the same to be enrolled in Her said Majesty's High Court of Chancery,
within six calendar months next and immediately after the date of the said in

page_text: part recited Letters Patent, as, reference being thereunto had, will more fully
and at large appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
Peter Arinand Lecomte de Fontainemoreau, do hereby declare the nature of
the Invention, and the manner in which the same is to be performed, are
particularly described and ascertained in the and by the following statement
thereof, that is to say:-
The discovery which forms the object of my Patent is, by certain processes
to substitute the use of certain sulphates, and of hydrosulphuric acid, for the
sulphur or pyrites used in the production of sulphate of soda and of muriatic
and nitric acids. These new processes depend upon two orders of reaction
which are made use of according to circumstances. The first order of reaction
consists in the direct use of certain sulphates, and more particularly of those
of alumina and of iron, to decompose common salt and chlorides generally,
and nitrates, by facilitating the action by heat and the vapour of water.
First, application of the sulphate of iron and of the sulphate of alumina to
the production of the sulphate of soda and muriatic and nitric acids.-The
sulphate which I employ in preference on account of its cheapness is the
direct produce of the lexivation of pyritic schists or alum clay, after the expo-
sure to the air and calcination having developped in it the formation of the
sulphate of iron and of the sulphate of alumina. When the alum clays con-
tain a sufficient quantity of soluble matter, they then may be directly mixed
with sea salt or other chlorides, but generally it is preferable to employ only
the products of the lexivation of these clays, and it is even better to allow at
first the sulphate of iron to separate from the concentrated liquids, to use only
the sulphate of alumina, then containing but a small portion of iron. This
precaution is useful when in the decomposition of the chloride the muriatic
acid is wished to be preserved, for without this separation it would be charged
with a too great quantity of sulphurous acid, an evil which however could be
avoided by adding to the mixture saltpetre or peroxide of manganese, to per-
oxidize the iron of the sulphate of iron, or in calcining a long time the sul-
phate under the action of a draught of air. The sulphate of alumina alone,
or mixed with the sulphate of iron, are thoroughly mixed with the chlorides
or with the nitrates, by slightly moistening the mixture. This mixture is
introduced in the ordinary apparatuses employed for the decomposition of sea
salt, and the heating is made in the usual manner, only it is necessary from
time to time to inject into the furnaces or cylinders a certain quantity of
water or of steam, so as to facilitate the decompositions and render them
more perfect; the decomposition is perfect at a temperature approaching a
dull red. This decomposition applics not only to sea salt, but likewise to all

page_text: And
chlorides and nitrates. When the muriatic acid finds an easy market, I turn
to use certain chlorides of no value, thus chloride of manganese (residue of
the manufacture of chlorine), chloride of calcium (residue in the manufacture
of ammoniacal salts), of the chloride of magnesium, which is found in the
mother liquor of salt works. As to the nitrates, the nitrate of lime, or the
direct produce of the evaporation of the lexivation of saltpetrous clays in
northern countries, may be used, but in general it is the nitrate of soda or
of potash which will be employed.
all the cases for the decomposition
of the nitrates, it is suitable for the sulphate of iron mixed with the sulphate of
alumina to be completely peroxidized. As to the proportions of the sulphates
and of the chlorides, or of the nitrates, they are variable according to the
pureness of these bodies; the proportions of acid contained in the sulphates
will be determined by considering this acid as free, and the proportions now
generally used for decomposing chlorides and nitrates by free sulphuric acid
may be adopted. This process, when it is applied to the decomposition of sca
salt, gives sulphate of soda mixed with alumina and sesquioxide of iron. The
sulphate of soda is separated from these oxides by the action of the water;
the residue can however be directly employed for the manufacture of artificial
soda. When it is required to decompose chlorides of manganese, of calcium,
and of magnesium, the residue is of no worth, the operation having been made
for the sole purpose of turning to account the chlorine of the chlorides to
convert it to the state of muriatic acid.
Secondly, application of the hydrosulphuric acid to the production of the
sulphate of soda, and of muriatic and nitric acids. For different commercial
purposes the hydrosulphuric acid is evolved in great quantities, and is wasted;
being thus a source of inconvenience; I have found a means of employing it
which is at once casy and economical, in making it enter into the manu-
facture of the sulphate of soda and of muriatic and nitric acids; that in many
localities sulphurets, such as those of calcium and barium, will be manufac-
tured, mostly with the intention of making use of the bydrosulphuric acid;
which results from their decomposition by carbonic or muriatic acids. In
other circumstances the residues of the lexiviation of artificial sodas will be
employed with more success than heretofore by the known processes. In-
stead of burning the hydrosulphuric acid, as has already been proposed, to:
convert it into sulphurous acid, and then to transform it into sulphuric acid
in lead chambers, I direct the gas, mixed with an excess of air, into the
chambers, by making it previously traverse a layer of nitric acid by means of
cascades or any other apparatus used to multiply the surfaces. of contact. I
have discovered that the contact of the hydrosulphuric acid with the nitric acid,
or the nitreous or hyponitric acids, converts it nearly totally and immediately

page_text: into sulphuric acid, with a slight deposit of sulphur when the hydrosulphuric
acid gas is mixed with a rather large quantity of air. The excess of air is
necessary, because the hydrosulphuric acid converts the nitric acid into deut-
oxide of azote, which, to act again as the nitric acid itself, must find in the
air the necessary oxygen to pass into the state of hyponitric acid or nitrous
acid. It results from this succession of reactions that a small portion of
nitric acid is necessary to transform a considerable quantity of hydrosulphuric
acid into sulphuric acid; the oxygen to be used in the transformation of the
sulphur, and of the hydrogen of the hydrosulphuric acid into sulphuric acid
and into water, being entirely taken from air. The reaction of which I speak
may, if more convenient, take place in large gritstone vessels, and thus one
may dispense with the use of the lead chambers. If the hydrosulphuric acid
mixed with air in lead chambers be only placed in contact with the gaseous,
nitrous, or hyponitric acid, there would be also formed sulphuric acid, but a
much greater part of the sulphur of the hydrosulphuric acid would be preci-
pitated in the state of solid sulphur, the combustion of which ought subse-
quently to take place by the ordinary process. The sulphuric acid obtained
by the method which I have just indicated, though a little nitrous, if it has
not been placed in contact with a sufficient quantity of hydrosulphuric acid
to denitrify it, may be usefully employed in the manufacture of sulphate of
soda and of nitric acid.
In recapitulation, the discoveries which form the object my Patent can be
enumerated, as follows, and I claim,―
First, the application of the sulphate of alumina and of the sulphate of
iron to the decomposition of sea salt, and in general of all chlorides and
nitrates.
Secondly, the employment of the chlorides of manganese, of calcium, and of
magnesium, to extract from them muriatic acid.
Thirdly, the manufacture of the sulphate of soda and of muriatic and nitric
acids, based on the transformation of the hydrosulphuric acid produced in the
decomposition of chlorides and nitrates. The hydrosulphuric acid serving for
this new. manufacture may be produced indirectly by the decomposition of
the sulphurets of calcium and of barium, of the residues of the lexivation of
artificial soda by means of hydrocloric and carbonic acids, or by any process
whatever.
In witness whereof, I, the said Peter Armand Lecomte de Fontaine-
moreau, have hereunto set my hand and seal, this Eleventh day of
December, in the year of our Lord One thousand eight hundred and
fifty
L. DE FONT (L.s.) AINEMOREAU.

page_text: AND BE IT REMEMBERED, that on the Eleventh day of December,
in the year of our Lord 1850, the aforesaid Peter Armand Lecomte de
Fontainemoreau 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.