【作者】 黄雁；

【导师】 王玉棉；

【作者基本信息】 兰州理工大学 ， 有色金属冶金， 2012， 硕士

【摘要】 砷通常作为铜精矿中伴生的有害元素，在铜冶炼的每一个工艺环节都会产生大量含砷的中间物料，砷的存在不仅对冶炼过程带来不利影响，同时也会带来环境的污染问题，危害人类健康。本研究以铜电解液净化环节产出的黑铜泥为原料，制备出在木材防腐上、玻璃清洁剂、农业资源等领域均有着广泛应用的砷酸铜、砷酸钠、三氧化二砷产品。探讨研究了由黑铜泥制备砷酸钠、砷酸铜、三氧化二砷的各环节工艺条件及其基础机理，主要完成了以下几个方面的工作：（1）确定了在最佳的碱浸工艺条件：NaOH浓度1mol/L、液固比10:1、温度85℃、反应时间6h、空气流量为0.8m³/h、搅拌速度为400r/min，此时As的浸出率约为92%，Cu、Sb的浸出率均小于3%。碱浸液蒸发结晶得到砷酸钠产品，碱浸渣采用Na₂S浸出回收残余的As。通过单因素实验，确定了硫化钠浸出碱浸渣的最佳工艺条件：NaOH溶液浓度为40g/L， Na₂S溶液浓度为160g/L，液固比为8:1，搅拌速度为400r/min，浸出时间为2.5h，浸出温度为85℃。此时As、Sb浸出率分别约为88%、90%。用氧化剂氧化硫浸液分离砷锑，氧化液通过蒸发结晶制备出砷酸钠，经检测砷酸钠含量为38.8%。（2）通过单因素实验和大量数据筛选确定了黑铜泥酸浸最佳工艺条件：H₂SO₄物质的量浓度1mol/L、液固比10:1、温度80℃、反应时间4h、空气流量为0.8m³/h、搅拌速度为400r/min，此时Cu的浸出率约为90%， As的浸出率约为89%。酸浸液蒸发结晶得到五水硫酸铜，其纯度达到98.01%，符合中华人民共和国硫酸铜国家标准（GB4371993）一级标准。砷酸铜制备的适宜条件为：反应温度为60℃，反应时间为1h，pH值为3.5，铜砷质量比为1.0～1.3。经XRD分析，砷酸铜产品的主要结构为Cu₅As₄O₁₅·9H₂O。砷酸铜产品的成分达到企业标准。酸浸渣通过Na₂S浸出回收残余As并制备出含砷酸钠为35.7%的产品。（3）确定由结晶后液制备三氧化二砷的工艺条件：pH值为0～1，反应时间为1h，反应温度为30℃。As₂O₃的纯度大于95%，达到有色金属行业标准（YS-T99-1997）中As₂O₃三级品标准。更多还原

【Abstract】 As the accompanying element of copper concentrate, arsenic always isharmful, and a large number of in-process materials containing arsenic willbe produced in each process of smelting. The existence of arsenic onlyadversely affect the smelting process, but also leads to environmentalpollution problems and is harm to humans healthy. In this paper, as rawmaterials, copper sludges which is produced in copper electrolytepurification process are used to prepare sodium arsenate、 copper arsenateand arsenic trioxide. they can be widely used in wood preservation、 glasscleaner and agricultural resource etc. In this subject, the various conditionsof preparation of sodium arsenate、copper arsenate and arsenic trioxide werestudied, and the basis of mechanism is analyzed. The following researcheshave been carried out:（1） The optimum process conditions of alkaline leaching of coppersludges are certain. The optimal process conditions of alkaline leaching areas follow： the reaction temperature is85℃, the ratio of liquid to solid is10:1, the NaOH concentration is1mol/L， the reaction time is6hours， theflowing rate of air is0.8m³/h， the stirring speed is400r/min. The resultshows that under the optimal conditions， the leaching rate of arsenic incopper sludges is about92%, while copper and antimony are less than3%.The alkaline residue is leaching for As by using sodium sulfide, theoptimum process conditions of sodium sulfide leaching of the residue aredrawn by single factor experiment. Under the conditions: the NaOHconcentration is40g/L, the Na₂S concentration is160g/L, the ratio ofliquid to solid is8:1, the stirring speed is400r/min, the reaction time is2.5hours, he reaction temperature is85℃. The result shows that under theoptimal conditions， the leaching rate of As and Sb in the alkaline residueare88%and90%, respectively. In order to separate As from Sb, the sodiumsulfide leaching liquid is oxidized by oxidizer. copper arsenate is preparedby evaporating, after mixing oxidation solution with alkaline leachingsolution. After testing, the content of sodium arsenate is38.8%in theproduct.（2） The optimum process conditions of acid leaching of copper sludges are certain by experimental research and mass of data. The optimal processconditions of acid leaching are as follow： the H₂SO₄concentration is1mol/L, the ratio of liquid to solid is10:1, the reaction temperature is80℃,the reaction time is4hours， the flowing rate of air is0.8m³/h， the stirringspeed is400r/min. The result shows that under the optimal conditions， theleaching rate of copper in copper sludges is about90%, he leaching rate ofarsenic in copper sludges is about89%. CuSO₄·5H₂O is obtained from acidleaching solution after evaporating and crystallizing, the product quality ofCuSO₄·5H₂O is up to the first grade standard of china（GB4371993）.Technological conditions of preparation of copper arsenate was drawn asfollow：the reaction temperature is60℃，the reaction time is1hour, the pHvalue is3.5, the Cu/As is1.0to1.3. Results of the analysis by XRD showthat the main structure of copper arsenate is Cu₅As₄O₁₅·9H₂O, Theproduction could basic met demands of enterprise standard. Sodiumarsenate is obtained through arsenic in acid leaching residue is leaching bysodium sulfide. After testing, the content of sodium arsenate is35.7%in theproduct.（3） The optimum process conditions of sulfur dioxide reduction arecertain. Under the conditions： the reaction time is1hours, the reactiontemperature is30℃, the pH value is from0to1. The purity of As₂O₃ismore than95%, the product quality of arsenic trioxide is up to the thirdgrade standard of nonferrous metal industry of china（YS-T99-1997）.更多还原