| 摘要 |
<p>PURPOSE:To collect Cu and valuable metals economically and in a high yield, by performing a leaching treatment of industrial by-products containing Cu and Pb, Zn, Fe, As, Ag, Cd, etc. together with solid sulfides under gaseous SO2 atmosphere by sulfuric acid. CONSTITUTION:The industrial by-products are subjected to the leaching treatment using sulfuric acid in the presence of solid sulfide of >=1 molecular ratio to the amount of Cu therein and under gaseous SO2 atmosphere at >=70 deg.C temp. Cu is precipitated selectively as copper sulfide, Zn, Fe, As, Cd etc. are eluted into the liquid and Pb, Ag are precipitated together with Cu as sulfides. The precipitates are refined to recover the metals. After separation of the precipitates, the solution is cooled to collect arsenious acid crystals. Then arsenic sulfide is obtained by gaseous H2S to perform dearsenation. The solution is neutralized with Na2CO3 to remove gypsum, Zn, Cd is recovered as the sulfides by gaseous H2S and Fe3O4 is precipitated by oxidizing air so as to remove iron.</p> |
