Composition and method for improved aluminum hydroxide production
AssigneeNalco Company
InventorsJianjun Liu, James A Counter, Dmitri L Kouznetsov, David H Slinkman
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Abstract
An improved method and composition for producing aluminum hydroxide crystals from precipitation liquor, involves the addition of an emulsified crystal growth modifier comprising a C8-C10 fatty acid, precursors, salts or blends thereof. The emulsified crystal growth modifier also facilitates an upward shift in particle size distribution of aluminum hydroxide and an upward shift in oxalate ball size.
Claims13
A process for recovering aluminum hydroxide crystals from a precipitation liquor comprising the steps of:
- (a) preparing a crystal growth modifier comprising:
- (1) a C8 to C10 fatty acid, precursor, salt or blends thereof and said carbon atoms free of functional groups, (2) an oil carrier, wherein said oil carrier content of said crystal growth modifier is greater than 15% by weight, and (3) water;
- (b) emulsifying the crystal growth modifier;
- and (c) adding the emulsified crystal growth modifier to the precipitation liquor;
- wherein the crystal growth modifier excludes polyalkoxylated non-ionic surfactant.
Aluminum hydroxide crystals produced by a process comprising adding a crystal growth modifier to a precipitation liquor, wherein the crystal growth modifier comprises:
- (a) a surfactant fatty acid, precursor, salt or blends thereof, the fatty acid having an alkyl chain length of C8 to C10 carbon atoms free of functional groups, dissolved in an oil having a boiling point above about 200° F. wherein an oil content of said crystal growth modifier is greater than 15% by weight, and emulsified in water;
- or wherein the crystal growth modifier consists essentially of (b) a surfactant fatty acid, precursor, salt or blends thereof, the fatty acid having an alkyl chain length of C8 to C10 carbon atoms, the carbon atoms free of functional groups, and emulsified in water;
- wherein the crystal growth modifier excludes polyalkoxylated non-ionic surfactant.
Aluminum hydroxide crystals produced by a process comprising adding a crystal growth modifier to a precipitation liquor, wherein the crystal growth modifier comprises:
- (a) a surfactant fatty acid, precursor, salt or blends thereof, said fatty acid having an alkyl chain length of C8 to C10 carbon atoms, said carbon atoms free of functional groups;
- (b) an oil having a boiling point above about 200° F. in which the fatty acid is dissolved wherein an oil content of said crystal growth modifier is greater than 15% by weight;
- (c) an emulsifier in an amount no greater than about 50% by weight;
- (d) a pH-adjuster;
- and (e) water in an amount within the range of from 0% to about 85% by weight;
- wherein the crystal growth modifier excludes polyalkoxylated non-ionic surfactant.
Dependencies are inferred from the claim text.