回收电镀废液制取鞣革剂方法的研究

Study on Method of Making Tanning Agent from the Recovered Waste Electroplating Liquor

在高浓度的含铬、铜电镀废液中加入亚硫酸钠还原Cr6+为Cr3 +;再加入硫化钠去除铜 ;然后加入氢氧化钠调节pH值使Cr3 +生成氢氧化铬沉淀 ;最后加入一定量硫酸溶解氢氧化铬制成鞣革剂———碱式硫酸铬 。

This paper presented the experimental researches on the recovering chromic hydroxide from the waste electroplating liquor to producing tanning agent.First,during suitable pH,sodium sulphite is added to reducing Cr 6+ to Cr 3+ .Second sodium sulfide is added to react with Cu 2+ forming copper sulfide.After filtration,adding sodium hydroxide into the filtrate,chromium hydroxide is produced.The chromium hydroxide is dissolved by certain sulfuric acid,then tanning agent is made from.The quality of water discharge reaches the national industry waste water discharge standard.