Improvements in Separating the Ammonium Chloride from Liquors Obtained in the Manufacture of Soda by the Ammonia-soda Process.
Year: 1886

page_text: Date of Application, 14th Aug., 1886.
Complete Left, 13th May, 1887.
Complete Accepted, 21st June, 1887
IRUVIDIONAL DIEUITIVATION.
Improvements in Separating the Ammonium Chloride from Liquors
Obtained in the Manufacture of Soda by the Ammonia-soda
Process.
I, GUSTAV JÁRMAY of Winnington near Northwich, Cheshire, Chemist, do hereby
declare the nature of this invention to be as follows:-
In the manufacture of soda by the ammonia soda process liquors are obtained
containing ammonium chloride, sodium chloride and carbonates of ammonium and
sodium ; in order to obtain ammonium chloride these liquors have hitherto been
treated by distillation to get rid of the carbonates and subsequent partial evaporation
and crystallisation. This necessarily involves a certain loss of ammonia, a great
expense in fuel and besides other difficulties a considerable wear and tear of plant.
My invention consists in separating ammonium chloride from these liquors direct,
by lowering the temperature of the liquors until a sufficient quantity of ammonium
chloride has crystallised out. According to the original strength of the liquor, this
quantity will be very different at different temperatures, but obtain a considerable
yield of ammonium chloride, I find it preferable to cool the liquors by means of
freezing mixtures or ice machines or other well known means below zero centigrade.
The ammonium chloride crystals so obtained can be separated from the liquors
either by filtration or by means of centrifugal machines or by any other well known
means. To the mother liquor as above obtained or even at the commencement of the
process to the original liquor, sodium chloride can be added and dissolved preferably
to saturation by means of heat or otherwise, and the liquor afterwards coolod when
an additional crop of ammonium chloride crystals is secured. The addition of salt and
subsequent cooling can be repeated if desired. The mother liquor can now be used
again instead of brine in the ammonia-soda process, thereby saving the expense of
distillation and effecting a great saving of the sodium chloride which is usually lost in
the mother liquor. If the ammonium chloride is required pure it may be washed
with water or a solution of ammonium chloride or may be subjected to
recrystallisation.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool,
Patent Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in Separating the Ammonium Chloride from Liquors
Obtained in the Manufacture of Soda by the Ammonia-soda
Process.
I, GUSTAV JÁRMAY of Winnington, near Northwich, Cheshire, Chemist, do
hereby declare the nature of this invention and in what manner the same is
to be perforined, to be particularly described and ascertained in and by the following
statement:-
In the manufacture of soda by the ammonia soda process, liquors are obtained con-
taining ammonium, chloride, sodium chloride, and carbonates of ammonium and
sodium; in order to obtain ammonium chloride, these liquors have hitherto been
distilled to get rid of the carbonates, and subsequently partially evaporated and
crystallised. This necessarily involves a certain loss of ammonia, a great expense in
fuel, and besides other difficulties, a considerable wear and tear of plant.
My invention consists in separating ammonium chloride from these liquors direct,.
by lowering the temperature of the liquors until a sufficient quantity of ammonium
chloride has crystallised out. According to the original strength of the liquor this
quantity will be very different at different temperatures, but to obtain a considerable
yield of ammonium chloride. I find it preferable to cool the liquors by means of
freezing mixtures or ice machines, or other well known means below zero centigrade.
The ammonium chloride crystals so obtained can be separated from the liquors
either by.filtration, or by means of centrifugal machines, or, by any other well known
means. To the mother liquor as above obtained, sodium chloride can be added, and
the liquor afterwards cooled, when an additional crop of ammonium chloride crystals
is secured. The addition of salt, and subsequent cooling can he repeated if desired.
The mother liquor can now be used again, instead of brine in the ammonia soda
process; thereby saving the expense of distillation, and effecting a great saving of the
sodium chloride, which is usually lost in the waste liquors of the ammonia soda
process, or instead of cooling the liquors repeatedly after repeated saturation with
soduim chloride, the quantity.of sodium chloride which the liquor can take up by
these repeated operations can be, added to the original liquor at once, and the mixture
cooled while, it is kept constantly agitated. In this way I obtain in one operation,
after separating the ammonium chloride, a mother liquor which can be used instead of
brine in the ammonia soda process. If the ammonium chloride is required pure, it
may be washed with water or a solution of ammonium chloride, or may be subjected
to re-crystallisation.
Having now particularly described and ascertained the nature of the said invention,
and in what manner the same is to be performed, I declare that what I claim is :-
1st. The process of separating ammonium chloride from the liquors obtained in the
ammonia soda process, which consists in dissolving in the liquor, sodium chloride,
refrigerating the resultant liquor, separating the crystals of ammonium chloride,

page_text: again warming and adding more sodium chloride, and again refrigerating and
separating the ammonium chloride, then finally using the mother liquor preferably in
the ammonia soda process, instead of brine, whereby the expense of distillation at
present incurred, is saved, and the sodium chloride remaining in the mother liquor is
utilised instead of having to be run to waste as is usually done with the waste liquors
after distillation.
2nd. The improvement in the process of obtaining ammonium chloride from
liquors obtained in the ammonia soda process, which consists in reducing the tempera-
ture by freezing mixtures or ice machines, or any other well known means, till a
sufficient quantity of ammonium chloride is deposited, and separating the so obtained
ammonium chloride.
3rd. The improvement in aforesaid process, which consists in adding sodium chloride
to the liquor, cooling the resultant liquor after complete solution, (by freezing
mixtures or ice machines, or any other well known means) till a sufficient quantity
of ammonium chloride is deposited, and separating the so obtained ammonium
chloride.
4th. The improvement in the aforesaid process, which consists in taking the residual
liquor after cooling, and after separating the ammonium chloride which is deposited,
warming it again, dissolving more sodium chloride, and again cooling and separating
the ammonium chloride which is obtained.
5th. The process for saving the residual sodium chloride in the ammonium chloride
liquor, which consists in adding an additional quantity of sodium chloride to it,
separating the ammonium chloride by refrigeration, and then using the mother liquor
in the ammonia soda process, instead of brine.
6th. The improvement in treating the residual liquors obtained in the ammonia
soda process, which consists in adding to these liquors a sufficient quantity of sodium
chloride, and cooling the mixture while it is kept constantly agitated, so as to obtain
in one operation crystallised ammonium chloride and a mother fiquor applicable in the
ammonia soda process in the place of brine.