由混合电镀污泥硫酸浸出液选择性沉淀分离铬的研究

Recovery of Chromium from Sulphuric Acid Leaching Solutions of Mixed Electroplating Sludge by Selective Precipitation

摘要: 研究提出了由混合电镀污泥硫酸浸出液选择性分离回收铬的方法。浸出液经萃取提铜后，应用磷酸沉淀方法实现铬与铁、镍、锌的选择性分离。实验证明，该方法稳定有效，能够达到选择性沉淀铬的目的，沉淀后液中铬的浓度可降至0.04 g/L左右。沉铬渣含铬约13%，镍、铁、锌等杂质含量可分别降至0.4%、0.1%和0.2%左右。由磷酸铬渣可进一步综合回收铬并制取铬的经济产品。

Abstract: The recovery of Cr from the sulphuric acid leaching solutions of mixed electroplating sludge (（MES)） is studied. After the removal of Cu by solvent extraction, the selective phosphate precipitation is applied for the separation of Cr from Fe, Ni and Zn in the MES leaching solutions . The experimental results show that the precipitation of Cr can be carri ed out stably and effectively and the concentration of Cr in the solutions can be lowered down to ~0.04 g/L. Cr is efficiently enriched in the precipitates which contain 13% of Cr, 0.4% of Ni, 0.1% of Fe and 0.2% of Zn respectively and could be further recovered as economic products.