Process for recovering cesium from cesium ore
AssigneeCarus Corporation
InventorPeter G. Mein
Life of this patent
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Abstract
Cesium is recovered from a cesium-bearing mineral such as pollucite by extraction with hydrochloric acid to obtain an extract of cesium chloride and other alkali metal and polyvalent metal chlorides. The iron and aluminum chlorides can be precipitated as the hydroxides and separated from the solution of the alkali metal chlorides to which is added potassium permanganate or other water-soluble permanganate to selectively precipitate cesium permanganate. The cesium precipitate is then separated from the residual solution containing the metal chlorides. The cesium permanganate, which is in a very pure form, can be converted to other cesium compounds by reaction with a reducing agent to obtain cesium carbonate and cesium delta manganese dioxide.
Claims16
A process for recovering cesium from a cesium-bearing mineral wherein the finely-divided mineral is extracted with aqueous hydrochloric acid (HCl) to obtain an aqueous acidic extract containing in solution cesium chloride (CsCl) together with rubidium chloride (RbCl), aluminum chloride (AlCl.sub.3) and other metal chlorides selected from the group consisting of potassium chloride (KCl), sodium chloride (NaCl), iron chloride (FeCl.sub.3), or mixtures thereof, wherein the improvement comprises
- (a) increasing the pH of said aqueous acidic extract to a pH of 2.5 to 3.0 or higher;
- (b) separating any precipitated metal hydroxide from the aqueous solution of CsCl;
- (c) adding a water-soluble permanganate to said aqueous solution and selectively precipitating cesium permanganate (CsMnO.sub.4) in the presence of other metal chlorides;
- and
- (d) separating the precipitate from the residual solution to obtain CsMnO.sub.4 of high purity.
In a process for recovering cesium from pollucite mineral wherein the finely divided mineral is extracted with hydrochloric acid (HCl) to obtain an aqueous acidic extract containing in solution cesium chloride (CsCl) together with the chlorides of rubidium, potassium, aluminum, and iron, said solution having been separated from the hydrated silicon dioxide precipitate formed in the extraction, wherein the improvement comprises:
- (a) treating the said aqueous acidic extract by adjusting its pH upwardly to a pH from 4.0 to 8.0 to precipitate polyvalent metal hydroxide;
- (b) separating the precipitated metal hydroxide to obtain an aqueous solution of CsCl together with other alkali metal chlorides;
- (c) adding potassium permanganate (KMnO.sub.4) to said aqueous solution to selectively precipitate cesium permanganate (CsMnO.sub.4);
- and
- (d) separating the precipitate from the residual solution of the other alkali metal chlorides to obtain CsMnO.sub.4 of high purity.
A process for recovering cesium from pollucite mineral wherein the finely divided mineral is extracted with aqueous hydrochloric acid (HCl) to obtain an aqueous acidic extract containing in solution cesium chloride (CsCl) together with rubidium chloride (RbCl), aluminum chloride (AlCl.sub.3) and other alkali chlorides selected from the group consisting of potassium chloride (KCl), sodium chloride (NaCl), iron chloride (FeCl.sub.3), or mixtures thereof, wherein the improvement comprises:
- (a) increasing the pH of said aqueous acidic extract to a pH of 2.5 to 3.0 or higher;
- (b) separating any precipitated metal hydroxide from the aqueous solution of CsCl;
- (c) adding a water-soluble permanganate to said aqueous solution and selectively precipitating cesium permanganate (CsMnO.sub.4) in the presence of other metal chlorides;
- (d) separating the precipitate from the residual solution to obtain CsMnO.sub.4 of high purity;
- (e) forming a slurry of the separated CsMnO.sub.4 in an aqueous alkaline solution containing a permanganate reducing agent;
- (f) reacting the CsMnO.sub.4 with said reducing agent to obtain cesium carbonate (Cs.sub.2 CO.sub.3) in solution and solid phase cesium delta manganese dioxide (Cs.sub.x.Mn.sub.4 O.sub.8-9 wherein x=0.8 to 2);
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- (g) separating the cesium carbonate solution from the cesium delta manganese dioxide.
Dependencies are inferred from the claim text.