Improvements in the Production of Alkaline Carbonates and Chlorine and their Derivatives.
Year: 1891

page_text: Date of Application, 25th Mar., 1891
Complete Specification Left, 21st Sept., 1891-Accepted, 24th Oct., 1891
Improvements in the Production of Alkaline Carbonates and Chlorine
and their Derivatives.
I, FARNHAM MAXWELL LYTE of 60, Finborough Road, London, S.W.
Analytical Chemist, do hereby declare the nature of this invention to be as
follows:-
My invention relates to a continuous process of producing alkaline carbonates
and chlorine, and their derivatives.
The formation of the alkaline carbonate is based on the decomposition of an
alkaline nitrate by heating with, say, calcic carbonate, the continued regeneration
of the nitrate being effected by the conversion of the recovered nitric acid into a
solution of a metallic nitrate, say plumbic nitrate, which on being precipitated with
a solution of say sodic chloride will yield a solution of the alkaline nitrate and a
precipitate of the metallic chloride.
The production of chlorine is effected by the electrolysis, whilst in a fused
state, of the said chloride, the metal recovered being oxidized for the next
operation.
The process is carried out as follows;-it being understood that wherever sodic
nitrate, sodic chloride, or sodic carbonate, is mentioned.the corresponding potassic
salt is to be understood.
Sodic nitrate mixed with, say, calcic carbonate is heated till it is completely
The nitrous fumes which
decomposed, the sodic carbonate being lixiviated out.
are here evolved may be passed into a suitable chamber where being submitted to
the simultaneous action of air, or oxygen, and water, they become converted into
aqueous nitric acid. A metallic oxide, say litharge or massicot, is then to be
dissolved in this nitric acid and the plumbic nitrate so formed may be precipitated
as plumbic chloride by the addition of brine. The plumbic chloride after being
washed and dried is to be fused and decomposed electrolytically as hereafter
described, to produce chlorine, and metallic lead for regeneration of the oxide.
The sodic nitrate formed at the same time as the plumbic chloride may be
evaporated and so recovered from its solution for use over again along with more
calcic carbonate for the regeneration of nitric acid. There are a variety of other
ways of producing plumbic chloride besides the above double decomposition, any of
which may be ntilized.
The decomposition of the chloride by electrolysis affords an easy way of
generating chlorine without the assistance of any oxidizing agent. The one
electrode should be composed of graphite or other material unattackable by
chlorine, and the operation should be conducted in a bell or closed vessel from
which, if conductive, the electrode should be insulated. This bell, as also the
vessel containing the fused plumbic chloride into which the bell dips, may be of
enamelled iron or be lined with or composed wholly of graphite or earthenware.
The other electrode may pass in at the bottom of the said vessel and be made of
iron tinned to ensure good electrical contact with the surrounding fused lead which
virtually forms an electrode of large area. The temperature of the fused chloride
being higher than that of molten lead, the fused metal will collect at the bottom
while the chlorine generated by the electrolysis of the chloride will rise in the bell
and pass out to a receiver. The molten metal being drawn off from below
whilst fresh chloride is added to the fused chloride, the process is rendered

page_text: The lead so obtained may be oxidised into massicot in the ordinary way, for
further treatment with the regenerated nitric acid above referred to.
Dated this 25th day of March 1891.
F. MAXWELL LYTE.
By A. M. & Wm. Clark,
53, Chancery Lane, London, Patent Agents.
COMPLETE SPECIFICATION.
Improvements in the Production of Alkaline Carbonates and Chlorine
and their Derivatives.
I FARNHAM MAXWELL LYTE of 60 Finborough Road, London, S.W.
Analytical Chemist, do hereby declare the nature of this invention and in what
manner the same is to be performed, to be particularly described and ascertained
in and by the following statement :-
My invention relates to a continuous process of conjointly producing alkaline
carbonates and chlorine and their derivatives.
The formation of the alkaline carbonate is based on the decomposition of an
alkaline nitrate by heating with, say, calcic carbonate, as shortly described by
Lunge, the process of my invention including, however, the regeneration of the
nitrate with the formation of a metallic chloride and the production therefrom of
chlorine in the manner hereafter described.
The regeneration of the alkaline nitrate is effected by the conversion of the
recovered nitric acid into a solution of plumbic nitrate which on being precipitated
with a solution of, say, sodic chloride, will yield a solution of the alkaline nitrate
and a precipitate of metallic chloride. From this chloride whilst in a fused state
chlorine is produced by electrolysis, the metal recovered being oxidised for the
formation of more plumbic nitrate, and so on repeatedly.
The process is carried out as follows:-it being understood that wherever sodic
nitrate, sodic chloride, or sodic carbonate is mentioned the corresponding potassic
salt may be substituted. To facilitate the comprehension of the process, I have
appended a diagram illustrating the cycle of operations to which I will refer, it
"being understood that the circles designated by reference letters indicate, not
apparatus, but the materials in the various stages of the process.
Commencing then at A; sodic nitrate mixed with calcic carbonate in the
proportions given by Lunge of, say, two equivalents of the former to two and a
quarter equivalents of the latter, is heated until it is completely decomposed, the
sodic carbonate formed then being lixiviated out and going to B, whilst the lime
remaining goes to C. The reaction which takes place at A may be expressed as
follows:-
2 NaNO3 + CaCO3 = Na2CO3 + 2 NO₂ + CaO + 0.
(If only a small amount of water be employed in this lixiviation, sodic carbonate
will be extracted. If a large amount of water be used the sodic carbonate will, on
heating, be converted into caustic soda with regeneration of the chalk.) The
nitrous fumes evolved during this decomposition are to be passed into a suitable
chamber where they are submitted to the simultaneous action of air or oxygen and
water and thus become converted into aqueous nitric acid. This operation is not
illustrated on the diagram.
Litharge or massicot is then to be dissolved in this nitric acid, say at D, and the
plumbic nitrate so formed is then to be precipitated as plumbic chloride by the
addition of a solution of sodic chloride (brine) at E. The plumbic chloride thus
formed after being washed and dried is to be fused and decomposed electrolytically
at F, as hereafter described, to produce chlorine which goes to G, and metallic
lead which goes to H for the regeneration of the oxide (litharge or massicot) ito be

page_text: used again at D. The sodic nitrate formed at E at the same time as the plumbic
chloride, is evaporated and so recovered from its solution for use over again at A
long with more calcic carbonate for the regeneration of nitric acid for continuing
he operation.
The decomposition of the plumbic chloride by electrolysis is effected in the
manner separately illustrated in the drawings. This electrolytical method affords
an easy way of generating chlorine without the assistance of any oxidizing agent.
The anode a should be composed of graphite or other material unattackable by
chlorine and the operation should be conducted in a bell or closed vessel b, from
which, if conductive, the anode should be insulated.
This bell b dips into fused plumbic chloride contained in a vessel c (which is kept
heated in any suitable manner) whilst the anode a is also immersed in the same
salt. The bell band vessel c may be of enamelled iron, or be lined with, or
composed wholly of, graphite or earthenware. The cathode d may pass in at the
bottom of the said vessel c and be made of iron tinned to ensure good electrical
contact.
The anode and cathode being in connection with the terminals of a suitable
source of electricity producing a current of low tension, say 2 to 5 volts, and the
temperature of the fused chloride being higher than that of molten lead, the fused
metal resulting from the decomposition of the chloride by the electric current, will
collect at the bottom and surrounding the cathode will virtually form a cathode of
large area, while the chlorine, also generated by the electrolysis of the chloride,
will rise in the bell b and pass out at e to a receiver. The molten metal being
drawn off from below at f, whilst fresh chloride is added to the fused chloride
above, the process is rendered continuous.
The lead so obtained is to be oxidized into massicot in the ordinary way for
further treatment at D with the regenerated nitric acid coming from E as before
described.
my said inven-
Having now particularly described and ascertained the nature of
tion and in what manner the same is to be performed, 1 declare that what I
claim is.
The herein described continuous process of conjointly producing sodic or potassic
carbonate and chlorine, which consists in decomposing sodic or potassic nitrate by
heating it with calcic carbonate, lixiviating out the sodic carbonate, and converting
the nitrous fumes evolved into aqueous nitric acid by the action of air or oxygen
and water, dissolving plumbic oxide in the nitric acid, precipitating plumbic
chloride by means of sodic or potassic chloride, fusing the plumbic chloride, and
decomposing it electrolytically to form chlorine and metallic lead for use over
again, as herein described.
Llated Senrember
Ilotoo
ontember ZIS LOW
F. MAXWELL LITE.
By A. M. & Wm. Clark,
53, Chancery Lane, London, Chartered Patent Agents.