Improvements in the Treatment of Apatite and other Mineral Phosphates, and Manufacture therefrom of Products suitable for Fertilizing Purposes.
Year: 1896

page_text: Date of Application, 5th Feb., 1896
Complete Specification Left, 7th Dec., 1893-Accepted, 5th Feb., 1897
Improvements in the Treatment of Apatite and other Mineral
Phosphates, and Manufacture therefrom of Products suitable
for Fertilizing Purposes.
I, JOHAN GUSTAF WIBORGH, of Kungstensgatan 17, Stockholm, Sweden,
Professor in the Royal School of Mines, Stockholm aforesaid, do hereby declare
the nature of this invention to be as follows:-
This invention relates to a method of rendering apatite and other mineral
phosphates more soluble and manufacturing therefrom products which I call
extra-phosphates" suitable for fertilizing purposes and containing a large
percentage of phosphoric acid.
According thereto, in order to render apatite or other mineral phosphate
(hereinafter included in the term apatite) more soluble, it is mixed with carbonate
of sodium or of potassium or with caustic soda or potash and the mixture sub-
sequently heated to a red or yellow heat in a suitable oven. The solubility of the
apatite in the citrate of ammonia of P. Wagner, will by this treatment, be
materially enhanced. If the apatite be impure, the proportion of alkali added
must be increased in a ratio depending on the amount and quality of the
impurities.
W. LLOYD WISE,
46 Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.
Improvements in the Treatment of Apatite and other Mineral
Phosphates, and Manufacture therefrom of Products suitable
for Fertilizing Purposes.
I, JOHAN GUSTAF WIBORGH, of Kungstensgatan 17, Stockholm, Sweden,
Professor in the Royal School of Mines, Stockholm aforesaid, do hereby declare
the nature of this invention and in what m. nner the same is to be performed to be
particularly described and ascertained in and by the following statement :-
This invention relates to a method of rendering apatite or analogous mineral
phosphates more soluble and manufacturing therefrom products which I call
extra-phosphate," suitable for fertilizing purposes and containing a large
percentage of phosphoric acid.
According thereto, in order to render apatite or other mineral phosphate
(hereinafter included in the term apatite) more soluble, it is pulverized and mixed
with a sufficient quantity of carbonate of sodium or of potassium or with caustic

page_text: soda or potash and the mixture subsequently heated to a red or yellow heat in a
suitable oven (the completion of the reaction being ascertained by the analyses of
samples taken from the mixture) in order to get a tetra calcium-sodium (or
potassium)-phosphate formed according to the following formula:
Thus 3 molecules of carbonate of sodium are required to 1 molecule of apatite.
If the apatite should contain feldspar (or silicic acid) for 1 molecule of feldspar,
2 molecules carbonate of sodium are needed, according to the formula:
KO
per
This tetra calcium-sodium (or potassium) phosphate is insoluble in water, but
easily soluble in the solution of citrate of ammonia of P. Wagner.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. The method of manufacturing from apatite or analogous mineral-phosphate a
fertilizer by heating to a red or yellow heat the mineral-phosphate together with
a sufficient quantity of carbonate of sodium or potassium or caustic soda or potash
so that a tetra calcium-sodium (or potassium)-phosphate is formed substantially as
described.
2. A fertilizer manufactured from apatite or analogous mineral phosphates
substantially as set forth in the preceding claim.
Dated this 7th day of December 1896.
the A
W. LLOYD WISE,
46 Lincoln's Inn Fields, London, W.C., Chartered Patent Agent.