Recovering strontium chloride from brine

Claim 1

THE METHOD OF RECOVERING STRONTIUM CHLORIDE FROM A BRINE CONTAINING WATER-SOLUBLE SALTS AMONG WHICH ARE STRONTIUM CHLORIDE, CALCIUM CHLORIDE, MAGNESIUM CHLORIDE, AND POTASSIUM CHLORIDE, AND WHICH MAY ALSO CONTAIN SODIUM CHLORIDE AND BORON SALTS, WHEREIN THE WEIGHT RATIO FO CALCIUM CHLORIDE TO STRONTIUM CHLORIDE IS AT LEAST 0.7 AND NOT MORE THAN ABOUT 120 AND THE AMOUNT OF CALCIUM CHLORIDE CONCENTRATION IN THE BRINE IS NOT IN EXCESS OF ABOUT 47.5 WEIGHT PERCENT TAKEN AT 30*C., WHICH COMPRISES (1) EVAPORATING SAID BRINE UNTIL SUBSTANTIALLY ANY SODIUM CHLORIDE PRESENT, AND A SUBSTANTIAL PORTION OF THE MAGNESIUM CHLORIDE AND THE POTASSIUM CHLORIDEHAVE PRECIPITATED AS CARNALLITE BUT AT LEAST ABOUT 6 PERCENT OF MAGNESIUM CHLORIDE BY WEIGHT OF THE THUS CONCENTRATED BRINE AND AT LEAST ONE MOLE OF MAGNESIUM CHLORIDE PER MOLE OF POTASSIUM CHLORIDE REMAINS IN SOLUTION IN THE BRINE, (2) COOLING THE THUS CONCENTRATED BRINE TO A TEMPERATURE OF BETWEEN ABOUT 50*C. AND 24.8*C. TO FORM, IN A CALCIUM CHLORIDE MOTHER LIQUOR, A SOLID PHASE PRODUCT OF THE REMAINING POTASSIUM CHLORIDE AND AT LEAST A SUBSTANTIAL PORTION OF THE REMAINING MAGNESIUM CHLORIDE AS CRYSTALLINE CARNALLITE TOGETHER WITH CRYSTALLINE STRONTIUM CHLORIDE, AND SOME ADHERING CALCIUM CHLORIDE MOTHER LIQUOR; (3) EFFECTING PHYSICAL SEPARATION OF THE SOLID PHASE HAVING A MINOR PROPORTION OF MOTHER LIQUOR ADHERING THERETO FROM A PREPONDERANT PORTION OF THE MOTHER LIQUOR; (4) ADMIXING WITH THE THUS SEPARATED SOLID PHASE AN AMOUNT OF WATER SUFFICIENT TO PROVIDE BETWEEN ABOUT 0.1 AND ABOUT 0.25 PART BY WEIGHT OF WATER PER PART OF TOTAL SOLIDS TO LEACH AND REMOVE THE STRONTIUM CHLORIDE AND ADHERING CALCIUM CHLORIDE MOTHER LIQUOR FROM THE CARNALLITE PRODUCT AND SEPARATING THE LEACHAATE CONTAINING A PREPONDERANCE OF THE CALCIUM CHLORIDE, STRONTIUM CHLORIDE, AND BORON PRESENT FROM THE SOLID PHASE CONTAINING THE MAGNESIUM CHLORIDE AND POTASSIUM CHLORIDE AND ANY REMAINING SODIUM CHLORIDE; AND (5) COOLING THE LEACHATE SO OBTAINED SUFFICIENTYLY TO CRYSTALLIZE OUT THE STRONTIUM CHLORIDE PRESENT LEAVING THE CALCIUM CHLORIDE AND BORON COMPOUNDS PRESENT IN THE LIQUOR AND THEREAFTER EFFECTING A PHYSICAL SEPARATION OF THE STRONTIUM CHLORIDE CRYSTALS SO FORMED FROM THE LIQUOR.

Claim 2

THE METHOD OF RECOVERING STRONTIUM CHLORIDE FROM A BRINE CONTAINING WATER-SOLUBLE SALTS AMONG WHICH ARE STRONTIUM CHLORIDE, CALCIUM CHLORIDE, MAGNESIUM CHLORIDE, AND POTASSIUM CHLORIDE, AND WHICH MAY ALSO CONTAIN SODIUM CHLORIDE AND BORON SALTS, WHEREIN THE WEIGHT RATIO FO CALCIUM CHLORIDE TO STRONTIUM CHLORIDE IS AT LEAST 0.7 AND NOT MORE THAN ABOUT 120 AND THE AMOUNT OF CALCIUM CHLORIDE CONCENTRATION IN THE BRINE IS NOT IN EXCESS OF ABOUT 47.5 WEIGHT PERCENT TAKEN AT 30*C., WHICH COMPRISES (1) EVAPORATING SAID BRINE UNTIL SUBSTANTIALLY ANY SODIUM CHLORIDE PRESENT, AND A SUBSTANTIAL PORTION OF THE MAGNESIUM CHLORIDE AND THE POTASSIUM CHLORIDEHAVE PRECIPITATED AS CARNALLITE BUT AT LEAST ABOUT 6 PERCENT OF MAGNESIUM CHLORIDE BY WEIGHT OF THE THUS CONCENTRATED BRINE AND AT LEAST ONE MOLE OF MAGNESIUM CHLORIDE PER MOLE OF POTASSIUM CHLORIDE REMAINS IN SOLUTION IN THE BRINE, (2) COOLING THE THUS CONCENTRATED BRINE TO A TEMPERATURE OF BETWEEN ABOUT 50*C. AND 24.8*C. TO FORM, IN A CALCIUM CHLORIDE MOTHER LIQUOR, A SOLID PHASE PRODUCT OF THE REMAINING POTASSIUM CHLORIDE AND AT LEAST A SUBSTANTIAL PORTION OF THE REMAINING MAGNESIUM CHLORIDE AS CRYSTALLINE CARNALLITE TOGETHER WITH CRYSTALLINE STRONTIUM CHLORIDE, AND SOME ADHERING CALCIUM CHLORIDE MOTHER LIQUOR; (3) EFFECTING PHYSICAL SEPARATION OF THE SOLID PHASE HAVING A MINOR PROPORTION OF MOTHER LIQUOR ADHERING THERETO FROM A PREPONDERANT PORTION OF THE MOTHER LIQUOR; (4) ADMIXING WITH THE THUS SEPARATED SOLID PHASE AN AMOUNT OF WATER SUFFICIENT TO PROVIDE BETWEEN ABOUT 0.1 AND ABOUT 0.25 PART BY WEIGHT OF WATER PER PART OF TOTAL SOLIDS TO LEACH AND REMOVE THE STRONTIUM CHLORIDE AND ADHERING CALCIUM CHLORIDE MOTHER LIQUOR FROM THE CARNALLITE PRODUCT AND SEPARATING THE LEACHAATE CONTAINING A PREPONDERANCE OF THE CALCIUM CHLORIDE, STRONTIUM CHLORIDE, AND BORON PRESENT FROM THE SOLID PHASE CONTAINING THE MAGNESIUM CHLORIDE AND POTASSIUM CHLORIDE AND ANY REMAINING SODIUM CHLORIDE; AND (5) COOLING THE LEACHATE SO OBTAINED SUFFICIENTYLY TO CRYSTALLIZE OUT THE STRONTIUM CHLORIDE PRESENT LEAVING THE CALCIUM CHLORIDE AND BORON COMPOUNDS PRESENT IN THE LIQUOR AND THEREAFTER EFFECTING A PHYSICAL SEPARATION OF THE STRONTIUM CHLORIDE CRYSTALS SO FORMED FROM THE LIQUOR.