The existence of Pb in crude antimony oxide powder(CAOP) hinders the further smelting and recovery of Sb and leads to some environmental problems. Therefore, the selective removal of Pb from CAOP is important for the production of high-purity antimony products. In this work, Pb in CAOP is removed by HNO3 leaching, achieving purification of CAOP. Then H2SO4 is used to recover Pb from the HNO3 leaching solution. The Pb leaching efficiency reaches 98.9 %, resulting in a decrease in the Pb content from 4.56 % to 0.20 % in CAOP. The Sb leaching efficiency is controlled at around 5.0 %. These confirm HNO3 has good selectivity. The HNO3 disrupts the molecular structure of the raw materials during the leaching, resulting in the conversion of Sb2O3 and As2O3 into insoluble AsSbO4. By adding H2SO4 to the leaching solution, the Pb precipitation efficiency reaches 93.6 %. After Pb removal, the leaching solution can be re-used for the leaching of Pb, while the residue can be directly returned to the pyrometallurgical system. The reaction mechanism and a novel approach for removing Pb from CAOP are proposed, which have the advantages of high selectivity, effective Pb separation, and recoverable HNO3.

中文翻译：

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高效去除和回收高砷氧化锑粉末中的铅


粗锑氧化物粉末（CAOP）中Pb的存在阻碍了Sb的进一步冶炼和回收，并导致了一些环境问题。因此，从 CAOP 中选择性去除 Pb 对于高纯度锑产品的生产非常重要。在本工作中，通过 HNO3 浸出去除 CAOP 中的 Pb，实现 CAOP 的纯化。然后使用 H2SO4 从 HNO3 浸出液中回收 Pb。Pb 浸出效率达到 98.9 %，导致 CAOP 中的 Pb 含量从 4.56 % 降低到 0.20 %。Sb 浸出效率控制在 5.0% 左右。这些证实了 HNO3 具有良好的选择性。HNO3 在浸出过程中破坏原料的分子结构，导致 Sb2O3 和 As2O3 转化为不溶性 AsSbO4。通过在浸出液中加入 H2SO4，Pb 沉淀效率达到 93.6 %。去除 Pb 后，浸出液可重新用于 Pb 的浸出，而残留物可直接返回火法冶金系统。提出了一种从 CAOP 中去除 Pb 的反应机理和新方法，该方法具有高选择性、有效分离 Pb 和可回收 HNO3 等优点。