Synthetic cristobalite
AssigneeStandard Oil Company (Indiana)
InventorJames A. Kaduk
Life of this patent
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Abstract
A method for preparing synthetic cristobalite comprises (1) preparing a mixture containing sources for an oxide of silicon and for an oxide of boron, a base of an alkali or alkaline earth metal or precursor of such base, a polyhydric alcohol, and water; and (2) maintaining the mixture at suitable reaction conditions to effect formulation of the cristobalite, said reaction conditions comprising a reaction temperature within the range of about 30.degree. C. to about 300.degree. C., a pressure of at least the vapor pressure of water at the reaction temperature, and a reaction time that is sufficient to effect crystallization.
Claims7
A method for preparing cristobalite, which comrises:
- (1) preparing a mixture containing sources for an oxide of silicon and for an oxide of boron, a base or precursor of such base, a polyhydric alcohol, and water, wherein the composition of the mixture of initial reactants in terms of mole ratios of oxides is:
- SiO.sub.2 /B.sub.2 O.sub.3 :
- 0.5-200
- R(OH).sub.n /B.sub.2 O.sub.3 :
- 0.01-20
- M.sub.2/v O/B.sub.2 O.sub.3 :
- 0.05-10
- H.sub.2 O/SiO.sub.2 :
- 2-5000
- wherein R is a polyvalent hydrocarbyl radical of 2 to about 5 carbon atoms, n is an interger of 2 to about 4, and M is at least one alkali or alkaline earth metal cation having a valence of v, or ammonium;
- and (2) maintaining the mixture at suitable reaction conditions to effect formulation of the cristobalite, said reaction conditions comprise a pH of the slurry prior to crystallization that falls within the range of about 9.0 to about 13.5, a reaction temperature within the range of about 30.degree. C. to about 300.degree. C. and a pressure of at least the vapor pressure of water at the reaction temperature.
Dependencies are inferred from the claim text.