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Preparation of unagglomerated metal oxide particles with uniform particle size

  • US 4,778,671 A
  • Filed: 07/14/1986
  • Issued: 10/18/1988
  • Est. Priority Date: 07/14/1986
  • Status: Expired due to Fees
First Claim
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1. A process for the production of substantially unagglomerated metal oxide particles having a mean diameter of up to about 1 micron and a substantially uniform particle size comprising:

  • (a) providing a solution of an oxygen-containing nitrate of a first metal selected from the group consisting of alkaline earth metals, lanthanide metals, transition metals exclusive of vanadium, tungsten, molybdenum, niobium and tantalum, and mixtures of these;

    (b) adding to the solution a chelating agent selected from the group consisting of tartaric acid, citric acid, and mixtures of these;

    (c) adding to the solution a base selected from the group consisting of ammonium hydroxide, urea, and mixtures of these;

    (d) drying the solution by heating for a time and at a temperature sufficient to remove substantially all the solvent from the solution to leave a solid residue; and

    (e) calcining the solid residue for a time and at a temperature sufficient to form particles of said metal oxide.

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