Method of synthesizing zirconium phosphate particles
AssigneeRenal Solutions, Inc.
InventorRaymond Wong
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Abstract
Zirconium phosphate particles are synthesized by providing a solution of zirconium oxychloride in an aqueous solvent, adding at least one oxygen-containing additive to the solution, the oxygen-containing additive being selected to form a complex with zirconium ions in the solution of zirconium oxychloride and thereby reduce hydration of the zirconium ions, and combining this solution with phosphoric acid or a phosphoric acid salt to obtain zirconium phosphate particles by sol gel precipitation.
Claims38
A method of making zirconium phosphate particles comprising:
- (a) combining at least one oxygen-containing additive with zirconium oxychloride in an aqueous solvent to form a solution wherein the oxygen-containing additive forms a complex with zirconium ions in the solution, and
- (b) combining the solution obtained in (a) with phosphoric acid or a phosphoric acid salt to obtain zirconium phosphate particles by sol gel precipitation,
- wherein said zirconium oxychloride and said phosphoric acid are introduced at a molar ratio of zirconium oxychloride to phosphoric acid of 1:2.8 to 1:3.2.
A method of making zirconium phosphate particles comprising:
- adding a solution of zirconium oxychloride and a solution of phosphoric acid simultaneously to a reaction vessel to obtain zirconium phosphate particles by sol gel precipitation.
A method of making zirconium phosphate particles comprising:
- (a) combining at least one oxygen-containing additive with zirconium oxychloride in an aqueous solvent to form a solution wherein the oxygen-containing additive forms a complex with zirconium ions in the solution, and
- (b) combining the solution obtained in (a) with phosphoric acid or a phosphoric acid salt to obtain zirconium phosphate particles by sol gel precipitation,
- wherein the oxygen-containing additive is sulfuric acid, sodium sulfate, sodium carbonate, isopropanol, glycerol, sodium lauryl sulfate, tartaric acid, polyvinyl alcohol, 2-amino-2-methyl-propanol, hydroxypropyl cellulose, tetrasodium N-( 1,2-dicarboxyethyl)-N-octadecyl sulfosuccinamate, octylphenoxypolyethoxy(9-10)ethanol, polyethoxylated(20) oleyl alcohol, ethylenediamine alkoxylate block copolymer, or combinations thereof.
A zirconium phosphate composition comprising a water-soluble zirconium phosphate polymer in an aqueous solution, wherein the polymer is formed by combining, in an aqueous solvent, zirconium oxychloride with at least one oxygen-containing additive that is capable of forming a complex with zirconium ions, wherein said zirconium phosphate composition, when dried, has a particle size distribution of less than 20% in the range of >60-120 microns, more than 80% in the range of 30-60 microns, and less than 10% in the range of less than 30 microns,
- an ammonia capacity of 15-20 mg NH4-N/gm ZP, and
- an Na+ content of 3.8-6.2 wt%, based on the weight of the zirconium phosphate particles.
Dependencies are inferred from the claim text.