Process for the production of dicalcium phosphate
AssigneesCommonwealth Scientific and Industrial Research Organization, Queensland Phosphate Limited
InventorsChristopher W. George, Hari N. Sinha, Mary R. Vujcich, Graham S. Walker
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Abstract
A process for the recovery of phosphate values from a phosphate ore, wherein the ore is leached with a mixture comprising water, sulphur dioxide and an organic carbonyl compound; the leach liquor containing dissolved phosphate values and calcium hydroxysulphonate is separated from any gangue and other insoluble material; and the leach liquor is treated to recover therefrom a phosphate-rich product and at least part of the sulphur dioxide and the carbonyl compound; characterized in that the leaching is carried out under conditions such that substantially no calcium hydroxysulphonate is precipitated at the leaching stage.
Claims10
In a process for the recovery of dicalcium phosphate from a phosphate ore, wherein the ore is leached with a mixture comprising water, sulphur dioxide and an organic carbonyl compound selected from the group comprising acetone, methyl ethyl ketone or methyl isobutyl ketone, cyclohexanone, acetaldehyde, formaldehyde and benzaldehyde;
- the leach liquor contains dissolved phosphate and calcium hydroxysulphonate and is separated from any gangue and other insoluble material;
- the improvement which comprises carrying out the leaching at a temperature in the range of from 10.degree. to 40.degree. C. and selecting the sulphur dioxide and carbonyl compound concentration such that substantially no calcium hydroxysulphonate is precipitated at the leaching stage;
- and treating the leach liquor to recover therefrom a dicalcium phosphate product and at least part of the sulphur dioxide and the carbonyl compound.
Dependencies are inferred from the claim text.