IMPROVEMENTS IN MEANS OF UTILIZING CERTAIN SILICATES AND ALUMINATES OF LIME AND OF MAGNESIA
Year: 1877

page_text: LETTERS PATENT to Ernest Solvay, of Brussels, in the Kingdom of Belgium,
Manufacturer, for the Invention of "IMPROVEMENTS IN MEANS OF UTILIZING
CERTAIN SILICATES AND ALUMINATES OF LIME AND OF MAGNESIA."
ealed the 18th May 1877, and dated the 12th January 1877.
PROVISIONAL SPECIFICATION left by the said Ernest Solvay at the Office of
the Commissioners of Patents on the 12th January 1877.
.
_ERNEST SOLVAY, of Brussels, in the Kingdom of Belgium, Manufacturer.
"IMPROVEMENTS IN MEANS OF UTILIZING CERTAIN SILICATES AND ALUMINATES
OF LIME AND OF MAGNESIA."
My Invention consists in means of utilizing the silicates and aluminates of lime
or of magnesia obtained in the treatment of chloride of calcium or chloride of
magnesium by means of silica, alumina, or silicate of alumina and air, or the vapour
of water, in order to obtain therefrom either chlorine or hydrochloric acid.
I have discovered that when chloride of calcium or chloride of magnesium is
subjected to the treatment herein-before referred to, soft silicates and aluminates of
lime or of magnesia are obtained; such silicates and aluminates having a special
nature or character which renders them eminently suited to chemical reaction, may
thus be utilized in various operations which would not be successful at all, or would
be far more difficult to carry out successfully with ordinary silicates and aluminates.
My Invention consists in applying such soft silicates and aluminates to various
new and useful operations, as herein-after described :—
Firstly. I apply such silicates and aluminates to the manufacture of chloride of
lime and of precipitated silica and alumina. I moisten suitably the said silicates
and aluminates, and I subject them to the action of chlorine, thus converting them
into chlorides (hypochlorites) of lime or of magnesia, the silica and the alumina set
free remaining mixed with the said chlorides. The said silica and alumina may be
separated from the said chlorides by any suitable well known means, such for
instance as lixiviation or washing, which dissolves principally the said hypochlorites
so as to allow of their being utilized separately from the silica and alumina. The
re-action may be effected in apparatus similar to what is used in the manufacture
of bleaching powder, and under similar conditions.
It will be understood that in the treatment just described calcium is to be pre-
ferred to magnesium as being less costly.

page_text: Secondly. I apply the said silicates and aluminates to the extraction of chlorine
from hydrochloric acid. I place the said silicates and aluminates in a suitable
receptacle, and I subject thein to the action of hydrochloric acid, either gaseous or
liquid. I thus convert them into chloride of calcium or chloride of magnesium, the
silica and the alumina set free remaining mixed with the said chlorides. I simply
dry the mixture, and disengage chlorine therefrom by heating it under the influence
of a blast or current of air, according to the process described in the Provisional
Specification filed by me at the Great Seal Patent Office on the 8th day of January
1877. Silicates and aluminates of lime or of magnesia are again formed, and these
may again be used when repeating the operation by the addition of a further
quantity of hydrochloric acid. I thus continue with the same lime and the same
silica or alumina, which may be used for any length of time (excepting that the
losses must be repaired) for converting any quantity of hydrochloric acid into
chloride of calcium or chloride of magnesium, from which chlorine may be extracted.
Thus I have invented a new and economical mode of extracting chlorine from
hydrochloric acid.
Thirdly. I apply the silicates and aluminates herein-before referred to, to the
production of precipitated silica and alumina by means of hydrochloric acid. For
this purpose I place the said silicates and aluminates in a suitable receiver, and I
subject them to. the action of gaseous or liquid hydrochloric acid. I thus convert
the said silicates and aluminates, as in the operation described under the second
head of this Invention, into chloride of calcium or chloride of magnesium, the silica
and alumina set free remaining mixed with the said chloride. I then separate the
silica and alumina from the chlorides of calcium or of magnesium by any suitable
known means, as for instance by lixiviation (after drying them previously); the
lixiviation dissolves the said chlorides so as to allow of the silica and alumina being
obtained separately. The chloride of calcium or of magnesium may then be treated
again by means of a further quantity of silica or of silicate of alumina, so as to
cause a further quantity of hydrochloric acid to be disengaged therefrom, and to
form again silicates and aluminates of lime or of magnesia; these latter are again
subjected to the action of hydrochloric acid, obtained as just described, and the
operation is continued, and thus, except that what is lost must be replaced, the same
quantities of hydrochloric acid and of lime or magnesia may be used for an indefinite
time to produce an indefinite quantity of silica and alumina.
The treatment just described furnishes thus a new mode of converting sand or
clay into precipitated silica and alumina, which may be applied by means of any of
the known processes to the various purposes for which it is advantageous to have
silica and alumina that is easily susceptible of re-actions.
The processes herein-before described under the second and third heads of this
Invention may be combined.
The extraction of chlorine from hydrochloric acid described under the second head
of this Invention may be combined with the manufacture of precipitated silica and
alumina described under the third head of this Invention. For this purpose it iş
only necessary to renew both the hydrochloric acid and the silica or silicates of
alumina.
Fourthly. I apply the silicates and aluminates herein-before referred to to the
manufacture of soda. I use the said silicates and aluminates of lime and magnesia
to regenerate the ammonia contained in the hydrochlorate of ammonia obtained in
For this purpose I
the process of manufacturing soda by means of ammonia.
introduce the said silicates and aluminates into the solution of hydrochlorate of
ammonia obtained in the said process, and I operate upon the said solution of
hydrochlorate of ammonia in the manner herein-before described in reference to
lime or magnesia. Chloride of calcium or chloride of magnesium is formed whilst
the ammonia is disengaged, and the silica and alumina set free remain in the liquid
with the undecomposed substances.
The substitution just described is without importance as regards the manufacture
of soda itself, but if the said manufacture be carried on in connection with a manu-

page_text: factory of chlorine or of hydrochloric acid by means of silica, of alumina, or of
silicates of alumina it is an improvement, for in that case after the well known
operations of decantation or filtering and of concentration the undecomposed sea
salt has been removed from the liquor, and on one hand there is chloride of calcium
or of magnesium, and on the other hand alumina and silica. Two processes may be
used for the purpose,-
First Process. If it be required to produce alumina or silica they are removed,
and the chloride of calcium is sent to the manufactory of chlorine or hydrochloric
acid, where by means of silica, alumina, or silicates of alumina, silicates and aluminates
of lime are obtained, which when sent back to the soda manufactory are used for
treating a further quantity of hydrochlorate of ammonia, and produce a further
quantity of silica and alumina, so that by continuing thus, any quantity of hydro-
chlorate may be treated, and any quantity of silica and alumina may be obtained
with the same lime and the same magnesia, allowing for losses which are repaired.
Second Process.--If it be not required to remove the silica and the alumina these
substances mixed with chloride of calcium are sent to the manufactory of chlorine
or of hydrochloric acid, the said mixture being well suited to the production of
chlorine and of hydrochloric acid under the influence of heat and of air or steam.
After the chlorine or hydrochloric acid has been extracted the silicates and aluminates
of lime are removed and sent back to the soda manufactory, where they are sub-
jected to a repetition of the operation, and so on, so that excepting the losses which
have to be supplied, not only the same lime or the same magnesium, but also
the same silica and alumina may be used continuously.
In the two processes herein-before described the preservation of the same lime or
the same magnesia allows the lime from the kiln in which the carbonic acid required
for the manufacture of soda is disengaged from the limestone to be utilized in the
manufacture of chloride of lime (bleaching powder) instead of its being consumed in
the disengagement of ammonia.
In the above description I have placed silicates and aluminates of magnesia in
juxtaposition with silicates and aluminates of lime, but I wish it to be understood
that iny Invention is of much less importance as regards the former than the latter,
for chlorine and hydrochloric acid are much more easily extracted from chloride of
magnesium than from chloride of calcium, and silica or alumina do not act equally
in the said process of extraction. It follows that the magnesian residuum does not
by any means contain the same quantity of, silicate or aluminate as the the cal-
careous residuum.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Ernest Solvay in the Great Seal Patent Office on the 26th June 1877.
ERNEST SOLVAY, of Brussels, in the Kingdom of Belgium, Manufacturer.
"IMPROVEMENTS IN MEANS OF UTILIZING CERTAIN SILICATES AND ALUMINATES OF
LIME AND OF MAGNESIA."
My Invention consists in means of utilizing the silicates and aluminates of lime
or of magnesia obtained in the treatment of chloride of calcium or chloride of
magnesium by means of silica, alumina, or silicate of alumina, and air or the vapour,
of water, in order to obtain therefrom either chlorine or hydrochloric acid.
:
I have discovered that when chloride of calcium or chloride of magnesium is sub-.
jected to the treatment herein-before referred to soft silicates and aluminates of lime
or of magnesia are obtained; such silicates and aluminates having a special nature
or character which renders them eminently suited to chemical re-action may thus
be utilized in various operations, which would not be successful at all, or would bo
far more difficult to carry out successfully with ordinary silicates and aluminates.
'
My Invention consists in applying such soft silicates and aluminates to various.
new and useful operations, as herein-after described,-

page_text: Firstly. I apply such silicates and aluminates to the manufacture of chloride of
lime and of precipitated silica and alumina. I moisten suitably the said silicates
and aluminates, and I subject them to the action of chlorine, thus converting them
into chlorides (hypochlorites) of lime or of magnesia, the silica and alumina set free
remaining mixed with the said chlorides. The said silica and alumina may be
separated from the said chlorides by any suitable well known means, such for
instance as lixiviation or washing, which dissolves principally the said hypochlorites,
so as to allow of their being utilized separately from the silica and alumina. The
re-action may be effected in apparatus similar to what is used in the manufacture of
bleaching powder, and under similar conditions.
It will be understood that in the treatment just described calcium is to be preferred
to magnesium as being less costly.
Secondly. I apply the said silicates and aluminates to the extraction of chlorine
from hydrochloric acid. I place the said silicates and aluminates in a suitable
receptacle, and I subject them to the action of hydrochloric acid, either gaseous or
liquid. I thus convert them into chloride of calcium or chloride of magnesium, the
silica and the alumina set free remaining mixed with the said chlorides.. I simply
dry the mixture, and disengage chlorine therefrom by heating it under the influence
of a blast or current of air, according to the process described in the Specification of
Letters Patent granted to me and bearing date the 8th day of January 1877, No. 77.
Silicates and aluminates of lime or of magnesia are again formed, and these may
again be used when repeating the operation by the addition of a further quantity of
hydrochloric acid. I thus continue with the same lime and the same silica or
alumina, which may be used for any length of time (excepting that the losses must
be repaired) for converting any quantity of hydrochloric acid into chloride of
calcium or chloride of magnesium, from which chlorine may be extracted. Thus
I have invented a new and economical mode of extracting chlorine from hydrochloric
acid.
Thirdly. I apply the silicates and aluminates herein-before referred to, to the
production of precipitated silica and alumina by means of hydrochloric acid. For
this purpose I place the said silicates and aluminates in a suitable receiver, and I
subject them to the action of gaseous or liquid hydrochloric acid. I thus convert
the said silicates and aluminates, as in the operation described under the second
head of this Invention, into chloride of calcium or chloride of magnesium, the silica
and alumina set free remaining mixed with the said chloride. I then separate the
silica and alumina from the chlorides of calcium or of magnesium by any suitable
known means, as for instance, by lixiviation (after drying them previously); the
lixiviation dissolves the said chlorides so as to allow of the silica and alumina being
obtained separately. The chloride of calcium or of magnesium may then be treated
again by means of a further quantity of silica or of silicate of alumina, so as to cause.
a further quantity of hydrochloric acid to be disengaged therefrom, and to form
again silicates and aluminates of lime or of magnesia. These latter are again subjected
to the action of hydrochloric acid, obtained as just described, and the operation is
continued, and thus, except what is lost must be replaced, the same quantity of
hydrochloric acid and of lime or magnesia may be used for an indefinite time to
produce an indefinite quantity of silica and alumina.
The treatment just described furnishes thus a new mode of converting sand or
clay into precipitated silica and alumina, which may be applied by means of any of
the known processes to the various purposes for which it is advantageous to have
silica and alumina that is easily susceptible of re-actions.
The process herein-before described under the second and third heads of this
Invention may be combined.
The extraction of chlorine from hydrochloric acid described under the second head
of this Invention may be combined with the manufacture of precipitated silica and
alumina described under the third head of this Invention. For this purpose it is
only necessary to renew both the hydrochloric acid and the silica or silicates of
alumina,

page_text: Fourthly. I apply the silicates and aluminates herein-before referred to to the
manufacture of soda. I use the said silicates and aluminates of lime and magnesia
to regenerate the ammonia contained in the hydrochlorate of ammonia obtained in
the process of manufacturing soda by means of ammonia. For this purpose I
introduce the said silicates and aluminates into the solution of hydrochlorate of
ammonia obtained in the said process, and I operate upon the said solution of
hydrochlorate of ammonia in the manner herein-before described in reference to
lime or magnesia; chloride of calcium, or chloride of magnesium is formed, whilst
the ammonia is disengaged, and the silica and alumina set free remain in the liquid
with the undecomposed substances.
The substitution just described is without importance as regards the manufacture
of soda itself, but if the said manufacture be carried on in connection with a manu-
factory of chlorine or hydrochloric acid by means of silica, of alumina, or of silicates
of alumina, it is an improvement, for in that case after the well known operations of
decantation or filtering and of concentration the undecomposed sea salt has been
removed from the liquor, and on the one hand there is chloride of calcium or of
magnesium, and on the other hand alumina and silica. Two processes may be used
for the purpose,-
First Process. If it be required to produce alumina or silica they are removed,
and the chloride of calcium is sent to the manufactory of chlorine or hydrochloric
acid, where by means of silica, alumina, or silicates of alumina, silicates and
aluminates of lime are obtained which, when sent back to the soda manufactory, are
used for treating a further quantity of hydrochlorate of ammonia, and produce a
further quantity of silica and alumina, so that by continuing thus any quantity of
hydrochlorate may be treated, and any quantity of silica and alumina may be
obtained with the same lime and the same magnesia, allowing for losses which are
repaired.
Second Process.--If it be not required to remove the silica and the alumina these
substances mixed with chloride of calcium are sent to the manufactory of chlorine or
of hydrochloric acid, the said mixture being well suited to the production of chlorine
and of hydrochloric acid under the influence of heat and of air or steam. After the
chlorine or hydrochloric acid has been extracted the silicates and aluminates of lime
are removed, and sent back to the soda manufactory, where they are subjected to a
repetition of the operation, and so on, so that, excepting the losses which have to be
supplied, not only the same lime or the same magnesia but also the same silica and
alumina may be used continuously.
In the two processes herein-before described the conservation of the same lime or
the same magnesia allows the lime from the kiln in which the carbonic acid required
for the manufacture of soda is disengaged from the limestone to be utilized in the
manufacture of chloride of lime (bleaching powder) instead of its being consumed in
the disengagement of ammonia.
In the above description I have placed silicates and aluminates of magnesia in
juxtaposition with silicates and aluminates of lime, but I wish it to be understood
that my Invention is of much less importance as regards the former than the latter,
for chlorine and hydrochloric acid are much more easily extracted from chloride of
magnesium than from chloride of calcium, and silica or alumina do not act equally
in the said process of extraction. It follows that the magnesium residuum does not
by any means contain the same quantity of silicate or aluminate as the calcarious
residuum.
Having now described the nature of my said Invention, and the manner of per-
forming the same, I claim as forming part of my said Invention the following
operations, herein-before described and carried out, by means of suitable and
sufficiently soft silicates and aluminates obtained in the processes of manufacture of
chlorine or hydrochloric acid by means of chloride of calcium and chloride of
magnesium, and silica or alumina or silicate of alumina :-
Firstly. The process consisting in obtaining by the action of chlorine on the said
•

page_text: •
silicates and aluminates, on the one hand chloride of lime or of magnesia, and on the
other band precipitated silica and alumina.
Secondly. The process of converting hydrochloric acid into chlorine by the inter-
mediary formation by means of the said silicates and aluminates of chloride of
calcium treated subsequently according to the Specification of my said Letters Patent
of 8th January 1877, No. 77.
Thirdly. The process of producing precipitated silica and alumina by the action of
hydrochloric acid upon the said silicates and aluminates.
Fourthly. The application of the said silicates or aluminates to the regeneration
of ammonia in the process of the manufacture of soda by means of ammonia, thus
by placing the soda manufactory in connection with a manufactory of chlorine or of
hydrochloric acid, according to the processes herein-before referred to, allowing the
same lime to be used repeatedly with or without the withdrawal of the precipitated
silica and alumina.
I wish it to be understood that I do not claim as forming part of my present
Invention the aforesaid manufacture of chlorine or hydrochloric acid by extracting
the same from chloride of calcium or chloride of magnesium under the influence of
heat and of a current of air or of steam, it being my intention, whilst respecting the
rights of others, to maintain those conferred upon me in respect of the said manu-
facture by other Letters Patent.
.
In witness whereof, I, the said Ernest Solvay, have hereunto set my hand
and seal, this Twenty-first day of June, in the year of our Lord One
thousand eight hundred and seventy-seven.
ERNEST SOLVAY. (L.S.)