Improvements in the Production of Compounds of Titanium,
Year: 1899

page_text: Date of Application, 25th Feb., 1899
PROVISIONAL SPECIFICATION.
Improvements in the Production of Compounds of Titanium,
We, FRANCIS MUDIE SPENCE and DAVID DICK SPENCE, both of the Manchester
Alum Works, Manchester, in the County of Lancaster, Chemical Manufacturers,
and HOWARD SPENCE, also of the Manchester Alum Works, Manchester, in the
County of Lancaster, Chemist, do hereby declare the nature of this invention
to be as follows:-
Hitherto it has been found impracticable to produce soluble compounds of
titanium on the large scale except at great expense.
By our invention we are enabled, at a considerably reduced cost, to produce
certain soluble, industrially useful, compounds of titanium from which various
other useful compounds of titanium may also be produced. We act upon suit-
able material containing titanic acid; such for instance as the waste solid product
from the manufacture of sulphate of alumina or of aluminoferric from bauxite,
with a suitable acid sulphate of an alkali-in order to render soluble the titanic
acid contained in such material. From the solution of the soluble matter which
we extract from the resultant product with water, or when necessary or desirable
with water and acid, or other suitable solvent we obtain a soluble crystalline
compound of sulphuric acid, of titanic acid and of the alkali of the acid sulphate
employed; such for instance as sulphuric acid, titanic acid and soda. Instead
of acting upon the material with an acid sulphate of an alkali we may dissolve
out its titanic acid with free sulphuric acid and add to the solution thus obtained
a suitable neutral sulphate of an alkali. From this solution we obtain under
appropriate conditions the soluble crystalline compound of sulphuric acid, titanic
acid and the alkali of the neutral sulphate employed. From this soluble crys-
talline compound we obtain by well known methods of chemical reaction various
other useful compounds of titanium.
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HOWARD
CHEETHAM,
Manchester, Agent to the Applicants.
Improvements in the Production of Compounds of Titanium.
We, FRANCIS MUDIE SPENCE and DAVID DICK SPENCE, both of the Manchester
Alum Works, Manchester, in the County of Lancaster, Chemical Manufacturers,
and HOWARD SPENCE, also of the Manchester Alum Works, Manchester, in the
[Price 8d.]

page_text: County of Lancaster, 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:
Hitherto no soluble compound of titanium has been produced on a large scale
as an article of commerce and the laboratory processes which have been des-
cribed are not suitable for the production of such compounds except at a price
which would be, practically speaking, prohibitive.
Now this invention relates to the production of soluble compounds of titanium
having the general formula TiO,,2 (SO), X20, (where X represents either sodium,
potassium or ammonium (NH), which general formula is based on the analysis
of the compounds dried at 100° Centigrade. From these soluble and indus-
trially useful compounds of titanium, (respectively, a crystalline compound of
titanic acid, sulphuric acid and soda, a crystalline compound of titanic acid,
sulphuric acid, and potash, and a crystalline compound of titanic acid, sulphuric
acid and ammonia) various other useful compounds of titanium may also be
produced. It should be noted that the said potash-salt, the formula of which
is TiO2 (SO), KO, differs from the well known compound of titanic acid, sul-
phuric acid and potash mentioned in the text books; the formula of which is
TiO3 (SO), K,O. In the process for producing the compounds now under
description a suitable material containing titanic acid, such for instance as the
waste solid product which results when manufacturing from bauxite, either sul-
phate of alumina, or what is known commercially as aluminoferric" or other
similar aluminous compounds (and which waste solid product may be obtained
-in-a-form-containing a considerable percentage of titanic acid) is acted upon
by fluxing it with acid sodium sulphate or sodium-pyrosulphate or acid potassium
sulphate or potassium pyrosulphate (approximately of the composition NaHSO
or Na,S,O, or KHSO, or K,S,O, or with acid ammonium sulphate) whereby the
titanic acid contained in the material treated is dissolved out or rendered
soluble. The acid ammonium sulphate is not so suitable for the fluxing process
as the corresponding acid sodium sulphate or acid potassium sulphate owing to
the volatility of ammonium compounds generally. Therefore although the use
of acid ammonium sulphate will give a satisfactory decomposition, it is better
to employ acid sodium sulphate or acid potassium sulphate when carrying out
the fluxing operation.
In carrying out this invention, the titanic acid may be obtained from sub-
stances other than bauxite.
Materials such as the minerals rutile or ilmenite may (after suitable preli-
minary treatment such for example in the case of rutile as fritting or fusing with
carbonate of soda and subsequent lixiviation of the product with water to remove
as much as possible of the soda) be used for the above mentioned fluxing process.
By way of illustration of the manner of carrying this invention into effect,
we will describe the preparation of the above mentioned soluble compound of
titanic acid, sulphuric acid and soda (TiO2 (SO), Na₂O.).
When treating waste material from bauxite if such waste material contains
twenty per cent. (or thereabout) of titanic acid a suitable proportion of acid
sodium sulphate would be about five parts by weight, either in the form of the
acid by-product from the manufacture of nitric acid, or of the similar by-product
from the decomposition of the nitrate of soda used in the manufacture of sul-
phuric acid by the chamber process, to one part of the above named waste material
when dried. It is desirable that the acid sulphate employed in attacking the
material containing titanic acid should contain sufficient sulphuric acid to form
approximately an acid sulphate or pyrosulphate (Na2S2O): The relative pro-
portions employed of the acid sulphate or pyrosulphate of the alkali and of the
material containing titanic acid may be varied considerably, according to the
nature of the material and the percentage of titanic acid it contains, so long as
the acid attack be such as to ensure that the titanic acid in the resulting product

page_text: shall be in the soluble condition which is necessary for the subsequent operations.
If during the fluxing operation a considerable proportion of the loosely combined
sulphuric acid of the acid sulphate employed is driven off by the heat necessary
for the reaction, such loss may be compensated for by the addition of more sul-
phuric acid during such operation. The sulphuric acid which may be so driven
off during the process may be condensed by any suitable means.
The fluxing operation may be carried out in any suitable manner, conveniently
it may be done by treating the said waste material from bauxite preferably in a
dried or powdered condition with the acid sulphate in an iron vessel such as is
used in the manufacture of nitric acid, taking care that the temperature employed
shall be sufficient to maintain the acid sulphate or pyrosulphate in a state of
fusion.
It may for example be carried out in connection with the manufacture of
nitric acid by decomposing the nitrate of soda employed with excess of sulphuric
acid in the presence of the material (preferably in a powdered condition) con-
taining titanic acid, and allowing the fused acid product to act upon such
material.
It may also for example be carried out in a similar manner in conjunction
with the decomposition of common salt (NaCl) by means of sulphuric acid,
employing such proportions that acid sodium sulphate is produced and allowed
to act upon the titanic-acid-containing material.
The resulting fluxed product thus-obtained is treated when cold with a suitable
solvent in such a manner as to dissolve out the soluble matter and at the same
time to prevent the separation of titanic acid in an insoluble form. This may
be conveniently carried out by employing as the solvent cold or hot or boiling
water or cold or hot or boiling dilute sulphuric acid, the separation of titanic
acid in an insoluble form being prevented by not allowing the acidity of the
solution (as determined by the well known method of titrating a small portion
of the liquid by standard alkali with methyl orange as indicator) to fall below
the point at which, on boiling the liquor and subsequently concentrating it,
the precipitation of titanic acid in an insoluble form would result. Having dis-
solved the soluble matter as above described, the next step is to separate the
undissolved matter from the liquor by filtration or other suitable means.
solution thus freed from insoluble matter is next concentrated by boiling the
solution in the ordinary way to effect the separation from it of the soluble crys-
talline compound of titanic acid, sulphuric acid and the alkali employed in the
acid sulphate.
The
When employing the proportions given above a separation of the crystalline
compound from the solution is largely effected when the solution is evaporated
to a specific gravity of about 14 (while hot), the temperature of the solution at
this point being about 110° Centigrade.
Of the two acid sulphates (respectively acid sodium sulphate and acid potas-
sium sulphate) the acid sodium sulphate is considered the more suitable to employ
because it is relatively the cheaper.
It is to be noted that the presence of a considerable proportion of alumina in
the material containing titanic acid is objectionable as it interferes largely with
the separation of the crystalline compound. If present in large proportion it
would very greatly reduce the quantity obtainable.
In those cases where the titanic acid in the material to be treated is readily
soluble in sulphuric acid, or has been so rendered soluble by a preliminary treat-
ment such as the above mentioned fritting or fusing with carbonate of soda, the
said material (instead of being acted upon with an acid sulphate of an alkali)
may be digested in heated sulphuric acid (either in the open or under pressure)
the quantity of sulphuric acid employed being in excess of what is actually
required for the solution of the titanic acid. The strength of the sulphuric acid
employed will necessarily vary with the character of the particular titanic-acid-
containing material under treatment. To the solution of titanic acid in sul-

page_text: phuric acid obtained as above described and then separated by any suitable
means from the insoluble matter there is added sulphate of the particular alkali
to be employed, (.e. either sulphate of soda, sulphate of potash or sulphate of
ammonia) preferably in the form of neutral or normal sulphate, such as neutral
sodium sulphate (Na,SO) the quantity added being sufficient to potentially form
some or all of the free or uncombined sulphuric acid present into an acid sul-
phate or bisulphate of the alkali. At this stage (as in the case of the solution
produced by attacking the material with the acid sulphate or pyrosulphate) the
solution is concentrated by evaporation by boiling in the ordinary way whereby
a separation is effected of the crystalline compound of titanic acid sulphuric acid
and the alkali employed.
The crystalline compounds separate out mainly during concentration of the
solution obtained by either of the above described methods.
If the solution contains impurities in such proportion as to be detrimental
the crystalline crop of the compound may be removed by well known means,
from the liquor whilst the latter is hot.
If however the solution is comparatively pure, it may be allowed to cool in
order to obtain as large a yield as possible of the compound.
The product thus obtained may be further purified, if necessary, by dissolving
it in dilute sulphuric acid of about 12 specific gravity, concentrating the solu-
tion so obtained, and again crystallizing out the compound. It is found that
this result is greatly assisted by the addition of sufficient neutral or normal sul-
phate of the alkali employed to convert potentially into an acid sulphate some
or all of the sulphuric acid that has been added in the form of dilute acid, as
above described. The addition of sufficient neutral sulphate of the alkali to
-potentially form about two thirds of the sulphuric acid so added into an acid
sulphate or bisulphate (NaHSO, or KHSO, or NHHSO) is a proportion-found
to give a good result. The mother-liquor resulting from the re-crystallisation
or recrystallisations may after concentration be again suitably employed for
attacking fresh material in the primary fluxing process in order to recover the
valuable materials contained in the liquor.
The soluble crystalline compound of titanic acid, sulphuric acid and of the
alkali employed, is in a very suitable form for use in the arts as a soluble tita-
nium compound, such for example as a mordant for colours, and is also suit-
able for the preparation (by well known methods of chemical reaction or of
double decomposition) of other useful compounds of titanium.
Having now particularly described and ascertained the nature of this said in-
vention and in what manner the same is to be performed, we declare that what
we claim is:-
1. The herein before described improvement in the production of soluble com-
pounds of titanium according to which a suitable material containing titanic acid
is acted upon by acid sodium sulphate or sodium pyrosulphate, acid potassium
sulphate or potassium pyrosulphate or acid ammonium sulphate whereby the
titanic acid in the said material is dissolved out or rendered soluble and from the
product resulting from such treatment of the said material the soluble matter
is extracted and the solution so extracted is concentrated by boiling so that a
soluble crystalline compound of titanic acid, sulphuric acid and the alkali of the
acid sulphate employed is obtained, all substantially as herein before described.
2. The herein before described improvement in the production of soluble com-
pounds of titanium according to which a suitable material containing titanic acid
in a condition in which it is readily soluble in sulphuric acid, (whether the
solubility of the titanic acid be a natural property or be brought about by suit-
able treatment of the said material) is acted upon by sulphuric acid, such acid
being in excess of the quantity actually needed for the solution of the titanic
acid and to the solution so obtained and separated from the insoluble matter an

page_text: alkaline sulphate is added and the resulting product is concentrated by boiling
so that a soluble crystalline compound of titanic acid, sulphuric acid and the
alkali of the sulphate employed is obtained all substantially as herein before
described.
3. As articles of manufacture the herein before described soluble crystalline
compounds of titanic acid sulphuric acid and alkali represented by the general
formula TiO2 (SO2),X,0, (where X represents sodium, potassium or ammonium).
Dated this Twenty-fifth day of November 1899.
HOWARD
CHEETHAM,
Manchester, Agent to the Applicants.