用乙酸-乙酸钠浸出及亚硫酸钠沉淀分离回收卡尔多炉渣中的铅  

Extraction and Recovery of Lead from Kaldo Slag by Acetate Acid and Sodium Acetate Leaching and Sodium Sulfite Precipitation

作　　者：吕建军[1] 肖连生[1] 张启修[1] 黄芍英[1] 胡磊[1] 曾之琪[1] 

机构地区：[1]中南大学冶金科学与工程学院,湖南长沙410083

出　　处：《矿冶工程》2013年第1期92-96,共5页Mining and Metallurgical Engineering

摘　　要：采用乙酸-乙酸钠溶液浸出卡尔多炉渣中的铅,用无水亚硫酸钠沉淀分离浸出液中的铅,沉铅滤液脱硫(加氢氧化钡)后返回浸出工序,研究了相关工艺参数对铝直收率及亚硫酸铅纯度的影响。结果表明:在搅拌速度为300 r/min,浸出温度为室温(25℃),乙酸、乙酸钠浓度分别为1 mol/L和2 mol/L,液固比5∶1,浸出时间2 h时,铅的浸出率可达到99.1%,浸出液含铅78.3 g/L;在搅拌速度200 r/min,沉淀温度为室温(25℃),无水亚硫酸钠过量系数1.25,沉淀时间20 min时,沉铅滤液余铅含量可降至4×10-6,亚硫酸铅纯度达到97.4%,铅的直收率可达到98%以上;沉铅滤液除硫酸根后,补充乙酸、乙酸钠至摩尔浓度分别为1 mol/L和2 mol/L,返回浸出工序,按浸出的最优条件处理同样的卡尔多炉渣,铅的浸出率可以达到98.1%,实现了浸出剂的闭路循环。Lead was leached from Kaldo slag using acetate acid and sodium acetate, then precipitated and extracted from the leaching liquor by sodium sulfite. The lead-extracted filtrate was returned to the leaching process after being desulfurized by barium hydroxide. The effects of related process parameters on aluminum recovery and lead sulfite purity were investigated. The results show that under the conditions such as stirring speed of 300 r/min, leaching temperature of 25℃, acetate acid concertration of 1 mol/L, sodium acetate concertration of 2 mol/L, liquid-solid ratio of 5 ： 1 and leaching time of 2 h, the leaching rate of lead can reach to 99.1%, with a lead content of 78.3 g/L in the leaching liquor. Under the following conditions： stirring speed of 200 r/min, precipitation temperature of 25℃, an excess coefficient of hydrous sodium sulfite of 1.25 and precipitation time of 20 min, the lead content in the lead-extracted filtrate can be decreased to 4×10^-6 while the purity of lead sulfite and lead recovery reaches to 97.4% and 98% respectively. After desulfurization, the filtrate is added with acetate acid and sodium acetate until the concentrations being 1 mol/L and 2 mol/L, respectively, then returned to the leaching process to treat the same slag under the optimum conditions. The leaching rate of lead can be up to 98.1%. A closed-circuit circulation of the leaching reagent is realized.

关 键 词：卡尔多炉渣 铅 浸出 乙酸 乙酸钠 亚硫酸铅 

分 类 号：TF812[冶金工程—有色金属冶金]