Process for the preparation of crystalline sheet-type alkali metal silicates
June 11, 2006. 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 ReferencesProcess for the manufacture of zeolites Process for the preparation of crystalline sheet-type alkali metal silicates Aluminosilicates having a zeolite structure, and process for the manufacture thereof Crystalline silicic acid, its salts, and processes for their preparation Process for preparing silica base for dentifrice Process for the preparation of crystalline sodium silicates Patent #: 4585642 InventorsApplicationNo. 06/872942 filed on 06/11/1986US Classes:423/332, Alkali metal containing (Li, Na, K, Rb, or Cs)23/295R, Crystallization23/300, With added material23/302T, Sodium compounds423/333By precipitating or gelling from silicate solutionExaminersPrimary: McFarlane, AnthonyInternational ClassesC01B 33/38 (20060101)C01B 33/00 (20060101) Foreign Application Priority Data1985-06-13 DEAbstractA process for the preparation of a crystalline sheet-type alkali metal silicate is described, in which an aqueous solution of an alkali metal silicate or a suspension of an amorphous alkali metal silica having a molar ratio M2 O (unneutralized)/SiO2, where M represents an alkali metal, of 0.05:1 to 0.8:1 is allowed to react at temperatures of 70° to 250° C. until the sheet-type alkali metal silicate crystallizes out. After the beginning of crystallization, an acidic compound is added in an amount such that an M2 O (unneutralized)/SiO2 ratio of 0.05:1 to 0.8:1 is constantly maintained in the mother liquor of a filtered sample. However, at least an amount corresponding to 5 milliequivalents of H+ per mole of SiO2 in the alkali metal silicate used is added. The use of seed crystals of the desired sheet silicate is advantageous.Other References
|
| ||||||||||||||
