含铜硝酸退镀液中铜的回收和硝酸的再生

Recovery of Copper and Regeneration of Nitric Acid from Waste Stripping Solution Containing Copper and Nitric Acid

用草酸铜沉淀法回收含铜硝酸退镀液中的铜并再生硝酸。研究了草酸加入系数(n_(草酸)∶n_(铜))、反应时间及反应温度等对沉淀效果的影响。确定的最佳工艺条件为:Cu^(2+) 136.52g/L,草酸加入系数0.9,搅拌速率300r/min,28℃,60min。在此工艺条件下,铜的沉淀率约为90%,草酸残留率小于1%,草酸铜产品的纯度达到98.33%。

Recovery of copper and regeneration of nitric acid from waste stripping solution containing copper and nitric acid was conducted by cupric oxalate precipitation method. Effects of the oxalic acid addition coefficient （the concentration ratio of oxalic acid to copper）, reaction time and reaction temperature on the precipitation effect were investigated. The optimum process conditions were determined as follows： Cu2＋ 136. 52 g/L, oxalic acid addition coefficient 0.9, stirring speed 300 r/min, temperature 28 ℃, time 60 min. Under these optimum conditions, the precipitation rate of copper was nearer 90%, and the retention rate of oxalic acid was less than 1%. In addition, the purity of copper oxalate reached up to 98.33%.