摘要 |
A method for recovering nonferrous metal values from hydroxide sludge wastes containing same by first chlorinating the aqueous waste to oxidize the chromium therein, separating the insoluble components therefrom and treating the resulting Cr(VI) solution in a fixed bed anion exchanger to separate the Cr(VI) from the solution, separating the copper from the aqueous solution by liquid-liquid extraction, separating the zinc from the copper-free solution by liquid-liquid extraction, precipitating and separating the aluminum in the form of hydroxide from the zinc-free solution and then separating the nickel from the aluminum-free solution by liquid-liquid extraction, and recovering the nonferrous metals from the respective solutions and precipitates by conventional procedures.
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