发明名称 |
Recovery of chromium values from waste streams by the use of alkaline magnesium compounds |
摘要 |
A process and a product formed thereby for the recovery of chromium values from aqueous solutions (e.g., waste liquors) comprises contacting an acidic solution containing sulfate ion and trivalent chromium ion with at least about 4 molar equivalents of MgO or Mg(OH)2 per 3 molar equivalents of trivalent chromium in addition to the amount required to neutralize the free acid to a pH of about 4 to form an amorphous, dense solid, grainy, easily settleable, trivalent chromium-containing precipitate in an alkaline solution according to the equation: 3Cr2(SO4) + 8 MgO ->Cr2(OH)4SO4 x 4Cr(OH)3 x 4H2O + 8 MgSO4. The trivalent chromium-containing product can be readily separated from the water and is a useful source of chromium for subsequent processing. The water remaining after separation of the precipitate contains less than 0.5 mg/l chromium.
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申请公布号 |
US4108596(A) |
申请公布日期 |
1978.08.22 |
申请号 |
US19770788583 |
申请日期 |
1977.04.18 |
申请人 |
REVERE COPPER AND BRASS, INCORPORATED |
发明人 |
HEMMING, DONALD C.;HAHN, ROBERT E.;ROBINSON, JR., JOHN W. |
分类号 |
C01G37/02;C14C3/06;(IPC1-7):C14C3/06;C01G37/00 |
主分类号 |
C01G37/02 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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