Process for removing solid organic materials and other impurities from wet-process phosphoric acid
AssigneeUranium Recovery Corporation
InventorsRalph E. Worthington, Donald A. Luke, Stanton L. Reese
Life of this patent
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Abstract
The solid organic materials contained in wet-process phosphoric acid are removed by froth flotation in a flotation cell in which the solid organic materials overflow with the foam from the top of the cell and the acid, after passing through the cell, is passed to extraction. The froth flotation process can also be used to remove defoamer and organic soluble materials from the wet-process phosphoric acid. Uranium in the partially purified phosphoric acid product is extracted with a suitable organic extractant, typically a mixture of mono- and di-(alkylphenyl) esters of orthophosphoric acid.
Claims19
A process for removing solid organic material from wet-process phosphoric acid derived from the acidulation of uncalcined phosphate rock by froth flotation comprising:
- (a) mixing the wet-process phosphoric acid and introducing gas into the wet-process phosphoric acid during the mixing to produce a foam containing at least a portion of the solid organic material;
- and
- (b) withdrawing the foam from the phosphoric acid.
A process for removing solid organic material from wet-process phosphoric acid which is derived from the sulfuric acid acidulation of uncalcined phosphate rock comprising:
- (a) mixing the wet-process phosphoric acid in a partially enclosed mixing zone at a sufficient speed and with the addition of a gas into the mixing zone to create a foam which entraps the solid organic material;
- (b) allowing the foam thus formed to overflow the mixing zone and thereby remove at least a portion of the solid organic material from the phosphoric acid;
- and
- (c) withdrawing phosphoric acid from the mixing zone which has said at least a portion of said solid organic material removed therefrom.
A process for removing organic solids from freshly produced wet-process phosphoric acid having a concentration of about 25 to 35% P.sub.2 O.sub.5 and containing uranium, inorganic solids including calcium sulfate and organic solids including humic acid solids, comprising mixing the phosphoric acid in a flotation cell at a temperature of about 50.degree. to 80.degree. C. in a manner such that foam is created entrapping at least a portion of the organic solids, permitting the foam to separate from the phosphoric acid, and removing the foam along with the entrapped organic solids and any entrained phosphoric acid overhead from the flotation cell.
A process for removing solid organic materials such as humic acids from wet-process phosphoric acid produced from uncalcined rock which also contains uranium and inorganic solids such as calcium sulfate by froth flotation comprising mixing the wet-process phosphoric acid in a flotation cell while passing gas through the cell, the phosphoric acid mixing and gas addition producing a layer of foam at the top of the flotation cell which contains the solid organic materials, the phosphoric acid being mixed with sufficient turbulence at the bottom of the flotation cell to keep the inorganic solids present in a suspended state while allowing the top of the cell to be substantially turbulence free, allowing the foam to overflow the top of the flotation cell and carry with it the solid organic materials, and removing relatively clean phosphoric acid as the underflow from the cell.
A process for removing defoamer and organic soluble materials from wet-process phosphoric acid derived from the acidulation of uncalcined phosphate rock which has been treated to remove a substantial portion of its organic solid material content, said defoamer and organic soluble materials being soluble in an organic extractant suitable for extracting uranium from wet-process phosphoric acid, comprising:
- (a) mixing the wet-process phosphoric acid and introducing gas into the wet-process phosphoric acid during the mixing to produce a foam containing at least a portion of the defoamer and organic soluble materials;
- and
- (b) withdrawing the foam containing said at least a portion of the defoamer and organic soluble materials from the phosphoric acid.
Dependencies are inferred from the claim text.