A Process for Preparing Plumbates of Calcium, Barium, and Strontium, and Employing the same for Oxidizing Purposes, and for Producing Oxygen and other Bodies.
Year: 1889

page_text: Date of Application, 26th July, 1889-Accepted, 14th Sept., 1889
VUMI DIN TULETUATION.
A Process for Preparing Plumbates of Calcium, Barium, and
Strontium, and Employing the same for Oxidizing Purposes, and
for Producing Oxygen and other Bodies.
I, CHARLES HUELSER, of the firm of Huelser & Co. of 142 Fleet Street, in the City
of London, Solicitors of Patents, do hereby declare the nature of this invention, a
communication to me from abroad by Georg Kassner of Neue Tunkernstrasse
No. 28, Breslau, in the Empire of Germany, Doctor of Philosophy, and in what
manner the same is to be performed to be particularly described and ascertained in
and by the following statement :-
Compounds of plumbic acid Pb O, H, and lime, baryta and strontia constituting the
formulae Pb 0, Ca,, Pb O, Ba, and Ph O, Sr, have hitherto not been produced, nor
were the properties of such compounds known.
The object of this invention is to produce the above compounds, as hereafter
described under 1 to III and to utilize the same for practical purposes in the manner
set forth under 1 to 5.
I. PLUMBATE OF CALCIUM.
Carbonate of lime, or caustic lime, or hydrate of lime, or a mixture thereof, is
mixed with oxide of lead, or carbonate of lead or red lead, or with any compound of
lead or mixture of the last named substances which produces oxide of lead when
heated with admission of air. This mixture, which is preferably made to contain one
atom of lead to every two atoms of calcium, is roasted while being exposed to the
admission of air for a sufficient space of time, thereby causing oxygen to be absorbed
from the air and. in case substances containing carbonic acid (carbonate of lead
carbonate of lime) have been employed, carbonic acid to be disengaged. When the
absorption of oxygen ceases, the preparation, viz. plumbate of calcium, is ready, it being
a body of yellowish red colour, which, in case the quantity of either of the substances
mixed had exceeded the proper atomic proportion, contains such excess as an
admixture of oxide or carbonate or hydrate.
This body has a dark colour and is produced in the manner as plumbate of calcium,
the corresponding compound of strontium being employed in lieu of the compound of
lime.
For the purpose of producing oxidations, the three new bodies are employed as
follows:
1) They are either placed together in aqueous liquid with the substance to be treated
and boiled therewith without any further addition, or carbonic acid is simultaneously
caused to act under or without pressure on the mixture of plumbate of lime, strontia
or baryta respectively and the substance to be oxidized.
2) They are previously mixed with water and decomposed by the action of gaseous
carbonic acid or by heating them with bicarbonated salts; subsequently they are
delivered of the soluble salts by subsiding and ablution and then placed together with
the substance to be oxidized.
3) They are previously decomposed by heating them, under high pressure a) with
water, or b) with carbonated salts in aqueous liquid, thereby obtaining as by-product

page_text: either a) the hydrates of the alkaliferous earths or 6) caustic alkali-lyes, and as main
product peroxide of lead or a mixture of the latter and carbonate of lime, baryta or
strontia. After removing the caustic alkali-lye, the insoluble mixture is allowed to
act on the substance to be oxidized.
Said insoluble mixture may however be rendered richer in peroxide of lead, by
removing the specifically lighter carbonates by ablution, and then used for oxidation
or treated as set forth in 4).
4) The three bodies or the insoluble product obtained therefrom as explained in 3)
are previously decomposed by means of other acids, for instance, nitric acid, acetic
acid, muriatic acid, or by boiling them with ammoniacal salts, for instance nitrate,
acetate or chloride of ammonium. The soluble parts having being eliminated, the
separated brown peroxide of lead is either produced independently in a pure state and
obtained as such, or the mixture containing this compound is made to act on the
substance to be oxidized or bleached.
5) The three bodies are employed for oxidations by mixing them with acids and
introducing the substances to be oxidized or bleached, during or after the mixing
process. To obtain oxygen, the insoluble product containing peroxide referred to
in 2) and 3) is slightly roasted. The modes of application 1) to 3) yield as product of
disoxidation, on passing carbonic acid through the substance, a mixture, insoluble in
water, of carbonate of lime, baryta or strontia respectively and carbonate of lead,
which, as elucidates from the production of the bodies, can serve again for regenerating
the plumbate of lime, baryta or stronția.
For this purpose the lastnamed mixture, after sufficient ablution and drying and
restitution of any lost constituents, is roasted with admission of air, till the absorption
of oxygen terminates, thereby reproducing the original compounds (Pb O Ca₂,
PbO Ba, and Pb O. Sr₂).
It is therefore nothing but the oxygen of the air which, in glowing heat, is
engaged by mixtures of the said bodies (oxide of lead and lime, baryta or strontia)
and is employed in the shape of plumbate of lime baryta or strontia either direct or
with the described modifications, or after transmission through other bodies; in case
such are used as intermedia, for instance red prussiate of potash.
Having now particularly described and ascertained the nature of this inven-
tion, and in what manner the same is to be performed I declare that what I
claim is:
1) The process for producing the compounds Pb O Ca₂, Pb ₁ Ba₁,
Pb O Sr, characterized by the roasting, with the admission of air, of a mixture
consisting on the one hand of oxide of lead, or in lieu thereof carbonate of lead, red
lead or such compounds of lead which produce oxide of lead when heated in the air,
on the other hand.
a) Of carbonate of lime or in lieu thereof caustic lime, or in lieu thereof hydrate
of lime, or a mixture of two or three of these substances, or
6) Of carbonate of baryta or in lien thereof caustic baryta or in lieu thereof
hydrate of baryta or a mixture of these two or three substances or
c) Of carbonate of strontium or in lieu thereof, caustic strontia or in lieu
thereof hydrate of strontia or a mixture of two or three of these substances
substantially as set forth.
2) The treatment of the bodies, produced according to claim 1), with carbonic acid,
bicarbonated salts, salts of ammonium or with acids, for the purpose of producing a)
pure peroxide of lead or b) mixtures of oxidizing property containing peroxide of
lead, substantially set forth.
3) The treatment of the bodies produced according to claim 1. either with water
at a high temperature and under a pressure of several atmospheres, or with solutions
of carbonated salts by heating under pressure for the purpose of obtaining.
a) Alkaline caustic lyes.
6) Mixtures of oxidizing property containing peroxide of lead, substantially as
cut farth

page_text: 4) The separation of the mixtures of oxidizing property referred to in claims 2
and by mechanical means, ablution centrifugal rinsing or such like, into one
part more, and another part less rich in peroxide of lead, substantially as set forth.
5) The application of the bodies or mixtures obtained according to claims 1, 2
and for oxidizing and bleaching and, by heating them in a dry state, for producing
oxygen, substantially as set forth."
6) The regeneration of all mixtures produced with the application of the bodies or
mixtures referred to in claims 1 to 5 and containing carbonate of lead and carbonates
of metalliferous earth or the oxides of both bodies, by roasting them, after drying,
with admission of air with or without the addition of fresh material, substantially as
set forth.
Dated this 26th day of July 1080
HUELSER & Co.,
Attorneys.