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进行了矿物学和化学的研究,以阐明在湿法炼锌过程的一些系统中银的行为。在～900℃锌焙烧的热力学分析指出,银矿物转变成金属银、硫酸银或氯化银。虽然工业焙砂的矿物学鉴定表明存在含银的氧化物和硅酸盐,但浸出试验证实大部分银是成可溶形的。在焙砂浸出时,大部分银以硫化银形态沉淀在残余的硫化物(尤其是闪锌矿)颗粒上。在中性浸出和高酸浸出的渣中,均观察到外缘包覆有银的闪锌矿。溶解度的测定也表明,硫化银是锌浸出系统中银的主要形式。在所有条件下,溶解后的银均大量结合入黄钾铁矾沉淀中,其他的硫酸盐或固体PhSO_4的存在量对结合的程度没有太大的影响。溶解于类似工业生产过程的合成溶液中的银,在工业条件下有90%以上结合进入沉淀的Na、NH_4或Pb黄钾铁矾中。
Mineralogical and chemical studies were conducted to elucidate the behavior of silver in some systems in the wet-process zinc refining process. Thermodynamic analysis of zinc roasting at ~ 900 ° C indicates that silver minerals are converted to metallic silver, silver sulfate, or silver chloride. Although the mineralogical identification of industrial calcine indicates the presence of silver-containing oxides and silicates, leaching tests confirm that most of the silver is soluble. During calcination, most of the silver precipitates on the remaining sulfide (especially sphalerite) particles in the form of silver sulfide. In neutral leaching and high acid leaching residues, silver-coated sphalerite was observed at the outer edge. Solubility measurements also show that silver sulfide is the major form of silver in the zinc leach system. Under all conditions, the dissolved silver was largely incorporated into the jarosite precipitate and the presence of other sulfates or solid PhSO 4 did not have much effect on the extent of binding. Silver, dissolved in a synthetic solution similar to industrial processes, is incorporated in precipitated Na, NH 4 or Pb jarosite by more than 90% under commercial conditions.