Process for Producing, Decomposing, Converting, or Transforming Compounds, and Reducing Metallic Compounds so Generated to Metallic State.
Year: 1895

page_text: COMPLETE SPECIFICATION.
Process for Producing, Decomposing, Converting, or Transforming
Compounds, and Reducing Metallic Compounds so Generated to
Metallic State.
I, HENRY SPENCER BLACKMORE, resident of the City of Mount Vernon,
County of West Chester, State of New York, United States of America, and by
occupation a 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 process for producing, decomposing, converting, or
transforming metallic compounds, and reducing same to metallic state together
with the production of materials employed to produce such transformation and
reduction, and the mode of their application, representing various steps in a
complete process for reduction of metals from natural products or compounds
particularly relating to those of an infusible or semi-fusible character, such as
those of the earth and alkali earth metals.
The object of my invention is to produce in an economical manner, purified
chemical compounds, from natural products chiefly of an infusible or semi-fusible
nature, and finally reducing the same to metallic state when so desired; and has
particular reference to the production of sulphides of such metals as aluminium,
magnesium, calcium, strontium, barium etc., and their reduction finally to metallic
state by action of molten or highly heated reducing agents as hereinafter described
but it is not limited to them as many other componds or metals may be likewise
produced, and consists essentially in dissolving or, in case of producing sulphides,
suspending, the infusible or semi-fusible oxides, or other compounds of such metals,
in a molten bath and exposing them in a heated condition to the action of carbon
disulphide vapor in which condition the oxide is transformed into sulphide with
the elimination of carbonic anhydride and carbon oxy-sulphide, then finally if so
desired converting the sulphides into metallic form by treatment with highly heated
or molten material or elements having greater affinity for sulphur than the metal
of sulphide thus produced, and preferably of greater specific gravity than the
molten bath of sulphides.
Among the oxides thus convertible to sulphides are alumina, magnesia, lime,
strontia and baryta, and reducing agents capable of being employed under various
conditions of affinity are lead, copper, zinc, iron, potassium cyanide etc., in highly
heated or molten condition preferably in state of fine sub-division.
As an illustration of the manner in which I carry out this process on a practical
basis, I will take for example the production of aluminium sulphide from natural
bauxite and reduction of the same to metallic aluminium.
The natural product, bauxite, employed consists of oxides of aluminium and
iron contaminated more or less with silica, this bauxite is first thoroughly dried
and pulverized, it is then dissolved in the molten bath consisting of fluorides and
sulphides of potassium and sodium in about equal portions, the object of using
potassium and sodium salts mixed is to produce a material melting at as low
temperature as possible, the mixture of alkali salts melting at a lower temperature
than either of them separate and independent; it is obvious that the molten bath
may cousist of various other substances which are capable of dissolving the infusible
or semi-fusible oxide treated, or sulphide produced, but have found the mixture of
alkali fluorides and sulphides to be the most efficient.
When the molten bath has become saturated with bauxite, apparatus is closed and

page_text: the saine.
a mixture of carbon disulphide and sulphur fluo-carbide vapor is passed through
The fluorine of the fluo-carbide combines with silicon (contaminating
the bath) converting the silica into gaseous silicon, tetra-fluoride, and remaining
carbon and sulphur combine with oxygen of silica producing carbon oxy-sulphide,
or carboxyl sulphide, which together with silicon tetra-fluoride escapes from the
apparatus, leaving the dissolved or suspended oxides free from silicon. The
carbon di-sulphide at the same time converts the alumina or aluminium oxide into
sulphide producing simultaneously carbonic anhydride and carbon oxy-sulphide or
carboxyl sulphide which escape in gaseous form. The same action takes place
converting the iron oxide present into sulphide.
I am fully aware that dry infusible aluminium oxide (alumina) has been
converted into aluminium sulphide by passing vapor of carbon di-sulphide over
it in its heated state but in that case the particles of aluminium oxide being
infusible at the temperature employed, is only transformed superficially into
sulphide which being fusible coats said particles thus preventing further action, the
richest product obtainable by this means being about 35 per cent. sulphide, the
balance being unconverted alumina, a process too expensive to be operated in a
commercial way, on account of great waste of aluminium oxide and difficulty of
reducing said sulphide on account of infusibility of the mass, being almost
impossible to reach sulphide with reducing agents, and when reduced to metal;
leaving same disseminating throughout the material in such a manner that it is
impossible to combine reduced metals in a button; by dissolving oxide in molten
bath there are no particles to coat, or by suspending the same in molten bath
capable of dissolving the sulphide produced, thus exposing fresh surfaces of oxide
to action according to this step of the process described, the difficulty is thus
entirely obviated.
The mixture of sulphides dissolved or suspended in the molten bath, produced
as aforesaid is exposed to the action of molten or highly heated iron or copper
in a finely divided state, which having greater affinity in its heated state, for the
sulphur combined with the aluminium, absorbs the same producing iron or copper
Bulphide and free metallic aluminium which being lighter than the surrounding
bodies ascends and accumulates on the top of the bath from whence it is withdrawn
at the end of the process and cast into ingots.
The iron or copper sulphide thus produced being less soluble in molten bath
remains suspended therein so long as reduction goes on, after which it gradually
settles and becomes molten at the bottom of the retort from which it is first
drawn, this being followed by the molten flux or bath of alkali fluoride and
sulphides which is afterward used over to dissolve more bauxite as before, and
finally the aluminium is withdrawn and cast into ingots.
The iron may be also introduced into the molten sulphide in a finely divided
state such as is known in commerce as "iron by hydrogen" this fine iron being
first heated to a bright red heat and gradually sifted or conveyed into the molten
bath the same reaction taking place as with the molten iron.
When molten iron is employed it is first passed through a firebrick sieve so that
the metal will be introduced into sulphide bath in fine streams or of fine shot
formation to admit of complete sulphurization of iron before reaching bottom of
retort, which is therefore preferably of considerable depth.
The carbon di-sulphide and sulphur fluo-carbide employed to transform oxides
into sulphides and remove silica is produced by heating carbon (charcoal) together
with a fluoride (such as lead fluoride) in a retort, to a low red heat, and then
passing the vapor of sulphur through the same, when the products distill, and are
passed through the bath as before stated.
It is obvious that any other liquid or volatile combination of carbon with other
electro-negative elements may be employed to convert the metallic oxide into
other binary compounds applicable for economical reduction, such as phosphorus
tellurium, selenium, etc., without departing from the spirit of my invention, which
consists essentially in couverting metallic oxides or other infusible or semi-fusible

page_text: compounds into compounds with other elements of electro-negative nature, by
dissolving or suspending the same in a molten bath and exposing it to action of
compounds of carbon and the other element a compound of which is desired, such
as carbon sulphide when sulphide is desired, and finally reducing said compound
produced in the bath by such action to metallic state, by mixing with a heated
element or compound having greater affinity for the electro-negative element
combined in the compound so produced, substantially as described.
Aluminium sulphide can also be reduced to metallic state by treatment with
potassium cyanide, the potassium cyanide absorbs sulphur producing potassium
sulpho-cyanide or thio-cyanate, care must be taken in this case not to have the
temperature too high otherwise the sulpho-cyanide will be dissociated into potassium
mellouide, potassium sulphide, free sulphur and carbon, in which case more or
less of the aluminium will be destroyed by free sulphur and bath saturated
with fine carbon so that it is almost impossible to combine metal into a mass or
button.
By dissolving a mixture or compound of silicon and aluminium oxides,
preferably certain clays (aluminium silicate) in molten bath aforesaid, and then
exposed to the action of carbon di-sulphide vapor alone, ultramarine may be
produced which can be finely separated from soluble constituents of molten bath
by lixiviation and filtration or decantation; the material preferably employed for
this purpose is kaolin, a clay consisting of a mixture of aluminium silicate and
undecomposed feldspar. The retorts employed are lined with carbon to protect
the same from solvent action of bath.
Alkali cyanides may also be produced by suspending iron carbide in molten
alkali sulphides and passing nitrogen gas through the molten bath producing at
the same time iron sulphide.
I do not claim the dissolving or suspending of various infusible or semi-fusible
substances treated under this process but simply the process of acting upon or
transforming them while thus dissolved or suspended by means of elements or
compounds brought in contact with the same, from a foreign source, and principally
relates to those substances which do not combine directly with molten bath or
solvent, forming definite compounds, except during introduction of the active agent
from a foreign source such as carbon di-sulphide in formation of aluminium
sulphide etc., as herein before described.
Also alkali carbonates or bi-carbonates may be produced from natural alkali
chlorides; such as sodium carbonate from common salt (sodium chloride). By.
suspending alumina (aluminium oxide) in molten bath of salt in closed receptacle
and passing superheated steam through the molten mass whereby the material is
transformed into sodium aluminate and hydrochloric acid which is conducted from
the apparatus when this re-action is complete, the steam is shut off and carbon
di-oxide is introduced in its stead when the sodium aluminate is transformed into
the sodium carbonate or bi-carbonate and free alumina which is used over.
I am aware that sodium silicate has been produced by mixing silica with common
salt (sodium chloride) and melting the same and then exposing to the action of
steam thereby eliminating hydrochloric acid but in that case the silica combines
directly with the molten compound when heated, forming sodium chlor-silicate
which by action of steam is decomposed into sodium silicate and hydrochloric
acid in which case it is readily seen that the silica is not dissolved or suspended in
the molten salt, but combined with the same, forming a definite compound, so
that when the steam is introduced from a foreign source, it reacts on compound
thus produced and not the silica per se dissolved or suspended in molten mass,
hence
the difference from my process can be readily seen.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manuer the same is to be performed, I declare that what
I claim is :-
1. The process for producing a fluo-carbide which consists in exposing carbon and

page_text: metallic fluoride in a heated state to the action of a volatile element (such as
sulphur, tellerium, selenium, etc.) a compound of which is desired.
2. The process for producing compounds of carbon and fluorine, with other
elements, which consists in passing the vapor of such elements over a mixture of
carbon and metallic fluoride, (such as lead fluoride) in a heated state, substantially
as described.
3. The process for producing sulphur fluo-carbide which consists in passing the
vapor of sulphur over a heated mixture of carbon and metallic fluoride, substantially
as described.
4. The process for eliminating silicon from a molten bath, containing the same
which consists in exposing said molten bath to the action of fluorine carbide or
compound of same, substantially as described.
5. The process for eliminating silicon from a molten bath or compound containing
the same, which consists in exposing said bath to the action of sulphur fluo-carbide,
substantially as described.
6. The process for eliminating silicon from a molten bath containing the same
which consists in exposing said bath to the action of a non-metallic fluo-carbide in
the form of vapor, substantially as described.
7. The process for converting metallic oxides into other compounds which
consists in the dissolving or suspending said oxides in a molten bath and exposing
the same to the combined action of carbon and sulphur or other element, a compound
of which is desired, substantially as described.
8. The process for producing, decomposing, converting, or transforming
compounds of an infusible or semi-fusible nature which consists in dissolving or
suspending the same in a molten bath and exposing it in a heated state to the action
of electro-negative elements or compounds of the same, substantially as described.
9. The process for producing, decomposing, converting, or transforming metallic
oxides which consists in bringing said oxides to molten or liquified state and
exposing it to the action of electro-negative elements or compounds of the same,
substantially as described.
10. The process for producing aluminium or other sulphide which consists in
exposing the molten or liquified oxides to the action of carbon di-sulphide vapor,
substantially as described.
11. The process for producing aluminium sulphide, which consists in dissolving
or suspending aluminium oxide in a molten bath and exposing the same in its heated
state to the combined action of carbon and sulphur, substantially as described.
12. The process for producing aluminium sulphide, which consists in dissolving
or suspending aluminium oxide in a molten bath and passing the vapor of carbon
di-sulphide over or through the same, substantially as described.
13. The process for producing a cyanide, which consists in suspending a metallic
carbide in a molten bath and exposing the same to the action of nitrogen gas,
substantially as described.
14. The process for producing alkali cyanide which consists in suspending carbide
of iron in a molten bath of alkali sulphide and introducing nitrogen gas into the
mixture, substantially as described.
15. The process for producing alkali salts from natural products, such as sodium
chloride, which consists in suspending or dissolving alumina in a molten bath of
said natural product and exposing the same to the alternate action of steam and
gaseous acid, a compound of which is desired, substantially as described.
16. The process for producing alkali carbonate, which consists in dissolving or
suspending alumina in molten bath of alkali chloride and subjecting the same to
the action of super-heated steam, thereby eliminating chlorhydric acid and
producing alkali aluminate, and finally introducing carbonic anhydride, substantially
as described.
17. The process for producing ultramarine which consists in dissolving kaolin or
feldspar in molten bath and exposing same to action of carbon di-sulphide vapor,
substantially as described.

page_text: 18. The process for reducing metals from their salts or combinations which
consists in dissolving the same in a molten bath and gradually exposing it to the
action of highly heated or molten reducing agents, substantially as described.
19. The process for producing aluminium from its compound which consists in.
dissolving said compound in a molten bath and gradually introducing in small
streams metallic iron or copper in a highly heated or molten state, substantially as.
described.
20. The process for reducing aluminium from its sulphides which consist in
exposing the molten or liquified sulphide to the action of finely divided iron or
copper in heated state, substantially as described.
21. The process for reducing aluminium, or other metals which consists in
gradually introducing reducing agents, in a finely divided heated state into a.
molten bath containing dissolved compounds of the metal desired, substantially as.
described.
22. The process for reducing aluminium or other metals from their combinations.
which consists in dissolving said combinations in a molten bath, and gradually
introducing highly heated reducing agents in a fine state of sub-division into the
same, substantially as described.
23. The process for reducing aluminium or other metals from their compounds.
which consists in bringing said compounds in a molten or dissolved state gradually
in contact with a highly heated molten reducing agent, substantially as described.
24. The process for reducing aluminium or other metals which consists in slowly
commingling said compounds in a molten or dissolved state with a highly heated or
molten reducing agent of greater specific gravity, substantially as described.
25. The continuous process for producing aluminium or other metals which
consists in exposing the molten or suspended oxides to the alternate action of a non-.
metallic carbide and a highly heated or molten reducing agent of greater specific
gravity, substantially as described.
26. The continuous process for producing aluminium and other metals which
consists in exposing molten metallic oxides to the alternate action of a non-metallic
carbide and a molten compound, (such as potassium cyanide) capable of absorbing
or combining with the combined electro-negative element liberating metal desired,.
substantially as described.
27. The continuous process for producing aluminium or other metal which.
consists in dissolving or suspending oxides of such metals in molten bath and.
exposing the same to the alternate action of a non-metallic carbide and highly
heated or molten material capable of absorbing or combining with the electro-
negative element of the compound so produced, and then withdrawing the products
of the reaction and the metal reduced, substantially as described.
28. The continuous process for reducing aluminium or other metals which consists.
in exposing the oxide dissolved or suspended in a molten bath to the alternate action.
of a non-metallic carbide and highly heated or molten reducing agent, substantially
as described.
29. In a process for producing compounds and reducing same to metallic state a.
molten flux or bath consisting of a mixture of fluorides and sulphides of the alkali
metals, potassium and sodium, substantially as described.
30. The process for producing aluminium from bauxite which consists in dissolving
the same in a molten bath consisting of fluorides and sulphides of potassium and
sodium, and eliminating the silicon from said bath by treatment with sulphur fluo-
carbide and then converting the dissolved aluminium oxide into sulphide by the
action of carbon di sulphide vapor and finally reducing said molten aluminium
sulpbide to metallic state by slowly introducing highly heated or molten iron in fine
streams at the same time producing iron sulphide, substantially as described.
31. The process for producing aluminium from bauxite which consists in dissolving
the same in a molten bath consisting of fluoride and sulphide, of alkali metals,
eliminating the silicon therefrom in the form of gaseous silicon tetra-fluoride by
exposing in the molten state the action of the compound formed by action of

page_text: sulphur vapor on heated mixture of carbon and heated metallic fluorides converting
the remaining de-siliconized molten aluminium oxide into sulphide by action of
carbon di-sulphide vapor and finally slowly and gradually exposing the molten
sulphide thus produced to the action of a highly heated or molten material having
greater affinity for sulphur thereby liberating the metal desired, substantially as
described.
32. The process for producing alkali aluminate which consists in exposing
aluminium oxide (alumina) dissolved or suspended in molten alkali salt, to the
action of steam, substantially as described.
33. The process for producing alkali aluminate and hydrochloric acid which
consists in exposing aluminium oxide (alumina) dissolved or suspended in molten
alkali chloride to the action of steam, substantially as described.
34. The process for producing, decomposing, converting or transforming
compounds which consists in exposing same while dissolved or suspended in molten
bath to the action of reagents or material introduced from a foreign source and
particularly of gaseous or vaporous form and being capable of combining or
reacting with suspended or dissolved matter or constituents of the bath or both
producing new compounds or products, substantially as described.
Dated this 10th day of December 1895.
WHEATLEY & MACKENZIE,
Agents.