富锡酸浸渣高压低酸选择性提铟工艺OA

The indium has been selectively extracted from the stann-rich acid leaching residue generated from tin smelting dust after dearsenic-zinc extraction by oxygen pressure acid leaching in a high-pressure reactor with sulfuric acid.The high-pressure reactor can enhance the leaching effect and improve the leaching rate of tin and indium from the acid leaching residue,and the effects of reaction temperature,sulfuric acid concentration,oxygen partial pressure,solid-liquid ratio,and reaction time on the leaching rate of tin and indium have been systematically investigated.The results of ICP,XRD,and EDS show that at the reaction temperature of 180 ℃,sulfuric acid concentration of 0.55 mol/L,oxygen partial pressure of 0.2 MPa,solid-liquid ratio of 1∶3 and reaction time of 180min,the leaching rate of indium reaches as high as 92.88％,while the leaching rate of tin is only 0.71％.Zinc stannate disappears from the leaching residue,while tin is mainly retained in the form of tin dioxide,which could be returned in the tin smelting process as a tin-containing raw material.Compared to atmospheric pressure leaching,oxygen pressure leaching can achieve high leaching rates of indium metal at lower acidity levels,while minimizing the leaching of tin,providing a new approach for extracting indium from tin-containing dust.Furthermore,the residue from leaching that includes indium can be directly reintroduced into the tin smelting process.