Double crystallization process to produce low organic, low silica soda ash
Patent 4286967 Issued on September 1, 1981. Estimated Expiration Date: 
June 27, 2000. 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.
June 27, 2000. 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 3838189 3904733 Process for producing soda ash from natural alkali metal carbonate-containing ores Patent #: 4158043 InventorsAssigneeApplicationNo. 06/163848 filed on 06/27/1980US Classes:23/298, From natural sources23/301, Seed23/302TSodium compoundsExaminersPrimary: Bernstein, Hiram H.Attorney, Agent or FirmInternational ClassesC01D 7/00 (20060101)C01D 7/37 (20060101) AbstractA process for the production of low organic, low silica, anhydrous sodium carbonate comprising (a) calcining raw trona ore to produce crude sodium carbonate containing soluble and insoluble impurities, (b) admixing said crude sodium carbonate with a substantially saturated sodium carbonate solution to produce sodium carbonate monohydrate crystals containing insolubles and an impure sodium carbonate solution; (c) separating these monohydrate crystals and impurities; (d) dissolving the monohydrate crystals to produce a substantially saturated sodium carbonate solution and insolubles; (e) separating said solution from the insolubles; (f) evaporative crystallization of the separated saturated sodium carbonate solution to produce pure sodium carbonate monohydrate crystals; (g) optionally, subjecting the crystals recovered in step (f) to steps (d-f) once, but no more than once; (h) heating said monohydrate crystals to obtain low organic, low silica, anhydrous sodium carbonate product particles; and (i) optionally, repeating the sequence defined by steps (b-h) once, but no more than once is disclosed.Field of SearchSeed | |
