Method for extracting tungsten from scheelite
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United States of America Patent
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Jul 8, 2014
Grant Date -
Aug 1, 2013
app pub date -
Mar 12, 2013
filing date -
Dec 24, 2010
priority date (Note) -
In Force
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Abstract
A method for extracting tungsten from scheelite by: 1) adding a mixed acid including H2SO4 and H3PO4 to a decomposition reactor; 2) heating the mixed acid to a temperature of 70-100° C.; adding scheelite while controlling the mixed acid present in an amount of 3-8 L per kg of scheelite; allowing the components in the decomposition reactor to react for 1-6 h, and filtering the resulting mixture to obtain a filtrate; 3) supplementing the filtrate with sulfuric acid consumed in the reaction; 4) crystallizing the filtrate to obtain phosphotungstic acid crystals and mother liquor; 5) dissolving the phosphotungstic acid crystals in water to obtain a phosphotungstic acid solution; 6) transforming the phosphotungstic acid solution into an ammonium tungstate solution for the purpose of preparing ammonium paratungstate; and 7) supplementing the mother liquor with phosphoric acid and water to an initial level and reusing the mother liquor for ore leaching.

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- 15 United States
- 10 France
- 8 Japan
- 7 China
- 5 Korea
- 2 Other
Patent Owner(s)
Patent Owner | Address | |
---|---|---|
CENTRAL SOUTH UNIVERSITY | YUELU DISTRICT CITY HUNAN PROVINCE 410083 CHANGSHA LUSHAN ROAD NO 932 CHANGSHA CITY HUNAN PROVINCE 410083 |
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Inventor(s)
Inventor Name | Address | # of filed Patents | Total Citations |
---|---|---|---|
Li, Jiangtao | Changsha, CN | 55 | 1189 |
Zhao, Zhongwei | Changsha, CN | 22 | 13 |
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