发明授权
- 专利标题: Method for recovering chromium from chromium-bearing material
- 专利标题(中): 从含铬材料中回收铬的方法
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申请号: US403078申请日: 1989-09-05
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公开(公告)号: US4966760A公开(公告)日: 1990-10-30
- 发明人: Judith A. Ladd , Joseph E. Ritsko
- 申请人: Judith A. Ladd , Joseph E. Ritsko
- 专利权人: Ladd Judith A,Ritsko Joseph E
- 当前专利权人: Ladd Judith A,Ritsko Joseph E
- 主分类号: C01G37/00
- IPC分类号: C01G37/00 ; C01G37/02 ; C22B3/14 ; C22B3/44 ; C22B34/32
摘要:
A method for recovering chromium from chromium-bearing material which comprises heating the material which can contain any one or combination of Co, Ni, Fe, Mo, and W with solid alkali metal hydroxide in an oxidizing atmosphere at 600.degree. C.-1000.degree. C. to form a fused material containing water soluble compounds of Cr, Mo, and W contained therein. The fused material is cooled and contacted with water to form a leach solution and a residue. The leach solution is adjusted to a pH of from about 5-8 with sulfuric acid, and a water soluble calcium salt is added. The chromium-rich liquor is then adjusted to a pH of 1-3 with sulfuric acid. Sodium metabisulfite is added to the chromium-rich liquor to reduce the chromium to the trivalent state after which the pH is adjusted to 5-8 with a base to form a precipitate of essentially all of the chromium.
公开/授权文献
- US5869435A Compositions for fracturing subterranean formations 公开/授权日:1999-02-09
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