The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 22, 1985
Filed:
Mar. 28, 1983
Truman P Moote, Tulsa, OK (US);
Robert L Reed, Tulsa, OK (US);
The Standard Oil Company, Chicago, IL (US);
Abstract
Magnesium is removed from brine by contacting the brine with calcium hydroxide at temperatures above about 80.degree. C. but below the boiling point of the brine. The contacting results in the formation of magnesium hydroxide precipitate which is substantially insoluble in the mother liquor at those temperatures and strontium hydroxide which is dissolved in the mother liquor. When the contacting is carried out at a temperature above about 90.degree. C., magnesium hydroxide precipitate is fast settling and filterable; accordingly, it is removed from the mother liquor by a conventional process, such as filtering. The mother liquor is then cooled to cause the precipitation of at least a substantial part of strontium hydroxide present in the mother liquor. The precipitate of strontium hydroxide is recovered by a conventional process such as filtering. If precipitation upon cooling is insufficient, carbon dioxide gas is introduced into the mother liquor to effect the precipitation of strontium hydroxide. Barium can be removed and recovered in the form of barium sulfate by reacting the remaining mother liquor with sodium sulfate. In order to produce a faster-settling precipitate of magnesium hydroxide, the brine is contacted with a sufficient amount of a solution or slurry of calcium hydroxide in water to bring the concentration of magnesium in the resulting liquid to the range from about 0.023 mols of magnesium per liter to about 0.04 mols of magnesium per liter.