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US 4,337,233 AGranted
Preparation of strontium nitrate from celestite and calcium nitrate
AssigneeFMC Corporation
InventorsJohn S. Chiang, David Goldstein
Life of this patent
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Abstract
Strontium nitrate is prepared by reacting celestite (strontium sulfate) with excess calcium nitrate in limited amounts of water, quickly extracting strontium nitrate from the reaction mixture by vigorous agitation with additional water, and recovering strontium nitrate by evaporation of the extract solution.
Claims16
The process of preparing strontium nitrate from celestite ore which comprises
- (a) mixing ground celestite ore with greater than a stoichiometric quantity of calcium nitrate in an aqueous reaction mixture to react strontium sulfate in the celestite with calcium nitrate, the reaction mixture containing insufficient water to solubilize all strontium values in the celestite as strontium nitrate;
- (b) contacting the reaction mixture, quickly and with vigorous agitation, with additional water to rapidly dissolve and extract soluble strontium nitrate reaction product, the total quantity of added water and reaction mixture water being from 100 to 140% of the amount required to solubilize essentially all of the strontium nitrate in the reaction mixture;
- (c) separating the aqueous solution containing solubilized strontium nitrate and unreacted calcium nitrate from the undissolved reaction mixture solids;
- (d) evaporating water from the separated aqueous solution to induce crystallization of strontium nitrate;
- and
- (e) recovering the strontium nitrate.
3 more elements
The process of preparing strontium nitrate from celestite ore which comprises
- (a) mixing ground celestite ore with greater than a stoichiometric quantity of calcium nitrate, the atomic ratio R of Ca:Sr being no more than 6:1, in an aqueous reaction mixture to react strontium sulfate in the celestite with calcium nitrate, the reaction mixture containing sufficient water to provide a water:strontium molar ratio of from 2(R-1) to 5.5(R-1);
- (b) contacting the reaction mixture, quickly and with vigorous agitation, with additional water to rapidly dissolve and extract soluble strontium nitrate reaction product, the total quantity of added water and reaction mixture water being from 100 to 140% of the amount required to solubilize essentially all of the strontium nitrate in the reaction mixture;
- (c) separating the aqueous solution containing solubilized strontium nitrate and unreacted calcium nitrate from the undissolved reaction mixture solids;
- (d) evaporating water from the separated aqueous solution to induce crystallization of strontium nitrate;
- and
- (e) recovering the strontium nitrate.
3 more elements
Dependencies are inferred from the claim text.