Title:
METHOD FOR PURIFYING OXIDE OR HYDROXIDE OF TANTALUM OR NIOBIUM
Document Type and Number:
Japanese Patent JP3407821
Kind Code:
B2
Abstract:
PURPOSE: To enable to purify Ta or Nb (hydr)oxide with inexpensive potassium hydroxide and a simple installation by treating the Ta or Nb (hydr)oxide containing impurities in a potassium hydroxide aqueous solution in a specific mode.
CONSTITUTION: A method for purifying the oxide or hydroxide of tantalum or niobium comprises treating the impurity-containing oxide or hydroxide of tantalum or niobium in a potassium hydroxide aqueous solution having a potassium hydroxide concentration of ≥130g/l, preferably ≥200g/l, at a temperature of ≥25°C, preferably ≥60°C, under the atmospheric pressure for 12hrs to dissolve the tantalum or niobium oxide or hydroxide as the potassium salt, subjecting the produced slurry containing the insoluble impurities to a filtration treatment for removing the impurities, adding an acid to the filtrate for precipitating the tantalum or niobium hydroxide, and subsequently recovering the precipitates.
Inventors:
Juntaro Kobayashi
Takuya Sasaki
Takuya Sasaki
Application Number:
JP5583494A
Publication Date:
May 19, 2003
Filing Date:
March 25, 1994
Export Citation:
Assignee:
Mitsui Mining & Smelting Co., Ltd.
International Classes:
C01G33/00; C01G35/00; (IPC1-7): C01G33/00; C01G35/00
Domestic Patent References:
| JP63295431A | ||||
| JP573717A | ||||
| JP3715601B1 |
Attorney, Agent or Firm:
Johei Yamashita
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