Improvements in the Manufacture or Production of Phosphorus and Compounds thereof.
Year: 1894

page_text: Date of Application, 17th Apr., 1894
Complete Specification Left, 11th Jan., 1895-Accepted, 16th Feb., 1895
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture or Production of Phosphorus
and Compounds thereof.
We ARTHUR SHEARER of 173 Ham Park Road and RALPH ROGER CLAPP
of 153 Earlham Grove, both in Forest Gate in the County of Essex Analytical
Chemists do hereby declare the nature of this invention to be as follows:-
This invention relates to the manufacture, or production, of phosphorus from
phosphate of alumina, and especially from native phosphate of alumina, which
usually contains phosphate of iron.
According to our invention we subject the phosphate to heat in the presence of
hydrochloric acid gas, a metallic chloride, and carbon. The metallic chloride used
may, for instance, be chloride of sodium, or of potassium, or of calcium, or a mixture
of these, and the carbon may for instance be wood, charcoal, coal or coke. The solid
materials employed should be ground or finely divided and intimately mixed, and be
introduced into a closed vessel, or retort, provided with an inlet for the hydrochloric
acid gas and an outlet for the produced vapours and gases.
The materials are subjected to an elevated temperature say a red heat, and
hydrochloric acid gas is passed over, into, or through, the materials during
heating.
.
We do not limit ourselves to precise proportions of the materials but the following
answer well. Native phosphate of alumina (containing for example 47 per cent. of
anhydrous phosphoric acid) 100 parts (by weight); common salt 120 parts and
carbon 32 parts.
The phosphorus distils over and can be burnt to form phosphorus acid and
phosphoric acid or it can be utilized to form other compounds of phosphorus or it
can be collected under water, and be purified in the usual, or any suitable, ways.
It is preferable to calcine the phosphate of alumina before grinding it and to
pass the hydrochloric acid gas before use through a scrubber to remove moisture.
Dated this 17th day of April 1894.
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, Loudon, W.C., Agents.
COMPLETE SPECIFICATION.
Improvements in the Manufacture or Production of Phosphorus
and Compounds thereof.
We ARTHUR SHEARER of 173 Ham Park Road, and RALPH ROGER CLAPP
of 153 Earlham Grove, both in Forest Gate in the County of Essex, Analytical
Chemists, do hereby declare the nature of our invention and in what manner the
same is to be performed to be particularly described and ascertained in and by
the following statement :-
This invention relates to the manufacture or production of phosphorus from
phosphate of alumina and especially from native phosphate of alumina which usually
contains phosphate of iron.
According to our invention we subject the phosphate to heat in the presence of
hydrochloric acid gas, a metallic chloride, and carbon.

page_text: The metallic chloride used may for instance be chloride of sodium or of potassium
or of calcium, or a mixture of these, and the carbon may for instance be wood,
charcoal, coal or coke.
The solid materials employed should be ground or finely divided and intimately
mixed, and be introduced into a closed vessel or retort provided with an inlet for
the hydrochloric acid gas and an outlet for the produced vapours and gases.
The materials are subjected to an elevated temperature say from a red to a white
heat and hydrochloric acid gas is passed over into or through the materials during
heating.
2
We do not limit ourselves to precise proportions of the materials but the following
answer well. Native phosphate of alumina (containing for example 47 per cent.
of anhydrous phosphoric acid) 100 (by weight) common salt 120 parts and
carbon 32 parts.
The phosphorus distils over and can be burnt to form phosphorous acid and
phosphoric acid or it can be utilised to form other compounds of phesphorus or it
can be collected under water, and be purified in the usual or any suitable ways.
It is preferable to calcine the phosphate of alumina before grinding it and to
pass the hydrochloric acid gas before use through a scrubber to remove moisture.
The part played by the hydrochloric acid and chloride may be represented, as
follows. Al,OP2O + 4 NaCl + 6 HCI + 8 C = (ALCI, 4 NaCI) + 8 CO +
P, 6 H which shews that by the treatment as aforesaid a double chloride of
aluminium and sodium (or other metal according to the chloride employed) is
formed this enabling the phosphoric anhydride which was combined with the
alumina to be set free and readily reduced to phosphorus by the carbon.
2
The reaction may be regarded as proceeding in two stages. The first stage
Al,O,PO, +4 NaCl + 6 HCI +3 C (AlCl 4 NaCl) + 6 H + 3 CO + P₂O,
requires a full red heat and is finished in about ten hours when the evolution of
carbonic oxide and hydrogen gases ceases for a time. The temperature is then
increased to near a white heat when in this second stage. Carbonic acid gas and
phosphorus come over according to the following equation P₂O, + 5 C = P₂ + 5 CO.
This is continued as long as phosphorus distils over. This second stage usually
lasts about thirty hours, but it depends upon the amount of phosphorus present.
Although in the main the above process may be regarded as taking place in two
stages as described yet some phosphorus is liberated during the first stage and to a
certain extent the formation of double chloride and phosphorus proceeds simul-
taneously the bulk of the phosphorus however distilling over between the tenth
and thirtieth hours of the operation.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed we declare that what
we claim is :-
-
1. The manufacture or production of phosphorus or compounds thereof from
phosphate of alumina by subjecting phosphate of alumina to heat in the presence
of hydrochloric acid gas, a metallic chloride and carbon substantially as herein-
before described.
2. The manufacture or production of phosphorus or compounds thereof by
intimately mixing ground or finely divided metallic chloride and carbon and calcined
phosphate of alumina and subjecting them to heat in a closed vessel or retort whilst
dried hydrochloric acid gas is passed into, over, or through them and obtaining
the phosphorus as such or as a compound thereof substantially as herein before
described.
Dated this 11th day of Lanuo 100%
JOHNSONS & WILLCOX;
47, Lincoln's Inn Fields, London, W.C., Agents.