IMPROVEMENTS IN THE MANUFACTURE OF ALKALINE PHOSPHATES
Year: 1884

page_text: I PHILIP MIDDLETON JUSTICE of 55 and 56 Chancery Lane in the County of
Middlesex, Fellow of the Institute of Patent Agents do bereby declare theo naturo
of said invention for "IMPROVEMENTS IN THE MANUFACTURE OF ALKALINE
PHOSPHATES" a communication to me from abroad by Lilian Eliza Thomas of
61 Avenue Marceau, Paris in the Republic of France, Spinster to be as follows:-
This invention relates to the manufacture of phosphates of the alkalies from
their chlorides by exposing these chlorides to the action of molten phosphoric iron
while other alkaline salts may be economically obtained by well known means
from the alkaline phosphates thus produced. I find that the decomposition of the
chlorides is greatly facilitated by mixing them with alkaline hydrates-The
decomposition of the hydrate at the high temperature employed, exercises a species
of inductive action on the chloride, and greatly promotes the displacement of the
chlorine by the phosphoric acid-I prefer to effect the mixture of the chloride
& hydrate before introducing them into the converting vessel. The salt should
considerably exceed in amount the hydrate employed.
Carbonate of Soda or carbonate of Potash or lime or magnesia or oxide of iron
may be sometimes conveniently added to the mixture. Notwithstanding the greater
cost of the alkaline hydrates as compared with chlorides I find the economical
results obtained from the mixture very superior to those obtained with chlorides
alone.

page_text: I PHILIP MIDDLETON JUSTICE of 55 and 56 Chancery Lane in the County of
Middlesex, Fellow of the Institute of Patent Agents do hereby declare the nature
of said invention for IMPROVEMENTS IN THE MANUFACTURE OF ALKALINE
PHOSPHATES, a communication to me from abroad by Lilian Eliza Thomas of
61 Avenue Marceau, Paris in the Republic of France, Spinster, and in what manner
the saine is to be performed, to be particularly described and ascertained in and by
the following statement :-
-
This invention relates to the manufacture of Phosphates of the Alkalies from
the Alkaline Chlorides by exposing such Chlorides to the action of molten
phosphoric iron in a converting vessel or furnace preferably having a basic
(Thomas & Gilchrist) or neutral lining, while other alkaline salts may be readily
and economically obtained by well known means from the alkaline phosphates
thus produced.
I have found that the decomposition of the alkaline chloride employed is greatly
facilitated by mixing with it some alkaline hydrate or caustic alkali the
decomposition of the hydrate at the high temperature employed exercising a
species of inductive action on the chloride and greatly promoting the displacement
of the chlorine by the nascent phosphoric acid.
I prefer to effect the mixture of the chloride and hydrate before introducing
them into the converting vessel, the mixture should always be as intimate as
possible and is preferably produced by adding to a strong caustic solution common
salt or potassic chloride until the mixture becomes nearly solid; the water should
then be driven off by evaporation the heat may be advantageously continued until
the mass fuses when it may be broken up into lumps and used in the furnace. The
chloride should always be much in excess of the caustic solution employed.
Carbonate of soda or potash or magnesia or oxide of iron may be conveniently
added to the mixture in order to diminish its volatility. The slag will contain the
phosphorus from the metal as an alkaline phosphate, more or less soluble in water
according to the amount of alkaline salt employed. It may be subsequently fused
with alkaline carbonate, hydrate or sulphate in order to render the whole or nearly
the whole of the phosphoric acid soluble in water.
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, as communicated to
me by my foreign correspondent, I declare that what I claim is
The Improvements in the manufacture of Alkaline Phosphates herein before
described which consists in adding to a bath of molten phosphoric iron during its
purification an intimate mixture of an alkaline chloride and hydrate substantially
as set forth.
Dated this twenty eighth day of July 1885.