焙烧-浸出黄钾铁矾渣中多种有价金属

实验研究了中低温焙烧-NH4Cl浸出-碱浸同时回收湿法炼锌黄钾铁矾渣中有价金属及Fe的新工艺. 黄钾铁矾渣在650℃下焙烧1 h后，渣中Zn, Pb的主要物相KFe3(SO4)2(OH)6分解为Fe2O3, ZnSO4和PbSO4. 在105℃、液固比10:2(w)条件下用6 mol/L NH4Cl浸出2 h，Zn, Pb和Cd的浸出率均在95%以上，同时Fe含量由焙烧后的23.21%提高到40%. 所得浸出渣再于160℃下用23.08%(w)的NaOH溶液浸出1 h，Fe含量可提高到54%左右，且As含量可降低到0.1%. 最终的浸出渣可作为铁精矿使用.

Recovery of Valuable Metals by Leaching of Roasted Jarosite Residue

A new process of roasting-ammonium chloride leaching-alkali leaching for recovery of valuable metals and iron in jarosite residue generated during zinc hydrometallurgy was studied by experiment. After roasting of jarosite at 650℃ for 1 h, the main phase of KFe3(SO4)2(OH)6 containing Pb and Zn was decomposed into Fe2O3, ZnSO4 and PbSO4. When the roasted jarosite residue was leached by 5 times with aqueous solution of 6 mol/L ammonium chloride at 105℃ for 2 h, over 95% of Zn, Pb and Cd in the jarosite was leached and the iron content was raised from 22% to 40%. The leached residue was further leached with 23.08%(w) NaOH solution at 160℃ for 1 h, Fe content in the final residue was 54%, which could be used as qualified iron concentrate.