IMPROVEMENTS IN PREPARATION OF CERTAIN OXIDIZING AGENTS, AND THE USE OF SUCH AGENTS FOR THE PREPARATION OF CHLORINE FOR BLEACHING, FOR YIELDING OXYGEN, AND FOR OTHER USEFUL PURPOSES
Year: 1869

page_text: PROVISIONAL SPECIFICATION left by William Henry Balmain at
the Office of the Commissioners of Patents, with his Petition, on
the 7th April 1869.
I, WILLIAM HENRY BALMAIN, of St. Helen's, Lancashire, do hereby
declare the nature of my said Invention for "IMPROVEMENTS IN
PREPARATION OF CERTAIN OXIDIZING AGENTS, AND THE USE OF SUCH AGENTS FOR
THE PREPARATION OF CHLORINE FOR BLEACHING, FOR YIELDING OXYGEN, AND FOR
OTHER USEFUL PURPOSES," to be as follows:-
In carrying out my process I avail myself of the known fact that
manganic acid, whether in combination with a base in the form of a
manganate or just set free, will rapidly and readily absorb oxygen,
whether alone or as it exists in the air, or as it might be mixed with
other gases and produce permanganic acid, or a permanganate, which
again will yield up readily to any substance capable of combining with it
a portion of its oxygen and return to the state of manganate, which again
on its part is ready to reabsorb oxygen and reproduce permanganate.
My manner of proceeding is to start with a small quantity of a solution
of permanganate made by any of the ordinary processes, the expense of

page_text: which is wholly unimportant, because the quantity required to start is
exceedingly small and will not have to be nenewed otherwise than by
the cheap process which I have now invented; this small portion of
permanganate I put into such a position that it shall be thoroughly
under my command to expose a large surface of it to air or oxygen by
any of the well-known means. Having got this arrangement working,
or ready to work, I gradually introduce into the solution the substance
which I wish to oxidise, and at the same time keep up the exposure to
the air, so that the air or oxygen shall restore the manganate formed
to the state of permanganate so rapidly as to insure that no manganate
shall be reduced to any lower state of oxidation. The degree of ex-
posure to the air being fixed or arranged the object just named can be
attained by keeping the quantity delivered of the substance in the act
of oxidation behind that which the permanganate is able to supply with
oxygen without all being made into manganate, so that there shall
always be some permangate in excess, which shall protect the manga-
nate from any demand for its oxygen. When the immediate object in
view is to form a quantity of permanganate with the air or oxygen
coming into contact with it, I gradually introduce into the solution
protoxide of manganese, carbonate of that oxide, or other convenient
oxide of manganese, either natural or artificial, in a state of fine division
suspended in water, together with an equivalent quantity of lime or other
base, regulating the quantity introduced so as not to let it be in excess
of that which the manganate is able to convert into permanganate.
The solution of permanganate thus resulting may then be employed, or
it may be concentrated more or less, and it may be used either on the
spot or elsewhere for producing chlorine with muriatic acid, or for
yielding oxygen, or for oxidizing, or for such other purposes in the arts
and manufactures where permanganate is or could be advantageously
employed, either in a solid or liquid form, for purposes useful in the
arts. This process also admits of application as a means of oxidizing
without in the first place accumulating all the oxygen as permanganate;
for instance if I wished to convert a low oxide of iron into a higher
oxide I start with a small quantity of a solution of permanganate, and
having arranged for its exposure to the air I gradually introduce the
low oxide of iron with the right degree of rapidity, and I have no need
to provide for the introduction of additional permanganate until the
quantity on which I am working becomes enormously disproportioned
to the bulk of the material upon which I am working, the manganate

page_text: here acting merely as a means of conveying oxygen to the iron by
re-forming permanganate as fast as the iron takes away that oxygen
which it contains over and above that which exists in manganate. In
like manner I can advantageously oxidize other substances besides oxide
of iron by putting them under similar conditions or circumstances and
using a manganate as a means of bringing to them oxygen from the air
or other sources. I have described the suspension of the substance to
be oxidized in a finely divided state suspended in water as a convenient
method, it may as in the case of effecting the oxidation of a metal or
other substance in lamps be more conveniently and with equal ad-
vantage be employed by insertion in the solution of permanganate in
such lumps as they may ordinarily occur, or to place them in a tower
or other convenient arrangement, and cause the permanganate solution
to pass through, it being only necessary to adjust the surface exposed to
oxidation, so that it shall not proceed sufficiently rapidly as to endanger
the reduction of any of the manganate to a lower stage than of oxidation.
In this manner lumps of native or artificial manganese oxides may
be used to produce permanganate, and many other modes of gradually
introducing the substance to be oxidized may be adopted, all that is
necessary being that it shall be so under command as to enable the
workman to insure that the manganate shall not be reduced, but only that
oxygen taken up which constitutes the difference between manganate
and permanganate.