Preparation of sodium carbonate monohydrate
Patent 3956457 Issued on May 11, 1976. Estimated Expiration Date: 
May 11, 1993. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
May 11, 1993. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 96374 3246962 3498744 3653848 InventorsAssigneeApplicationNo. 187578 filed on 10/07/1971US Classes:423/206.2, Alkali carbonate from trona23/302T, Sodium compounds423/421Alkali metal containing (Li, Na, K, Rb, or Cs)ExaminersPrimary: Vertiz, O. R.Assistant: Straub, Gary P. Attorney, Agent or FirmAbstractSodium carbonate monohydrate from crude trona is prepared by calcining the crude trona to crude sodium carbonate, dissolving the crude sodium carbonate in an aqueous solution, clarifying and filtering the resulting solution to remove insoluble material to form a carbonate process solution, subjecting the carbonate process solution to a first crystallization to form a first crop of sodium carbonate monohydrate crystals from said carbonate process solution, subjecting the mother liquor separated from the first crop of monohydrate crystals and having a higher concentration of soluble organics to a second crystallization, including a crystallization temperature higher than that employed to obtain the first crop of said monohydrate crystals, to effect formation of a second crop of sodium carbonate monohydrate crystals, and separating said second crop of monohydrate crystals from a mother liquor having an organics level higher than said carbonate process solution and said mother liquor separated from said first crystallization. |
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