【作者】 李伟；

【导师】 郭学益；

【作者基本信息】 中南大学 ， 有色金属冶金， 2014， 硕士

【摘要】 本研究以大冶有色金属公司铜冶炼副产品粗硫酸镍为对象,以生产电池级硫酸镍产品为目的,对其进行了精制处理。结合原料特点以及生产实际,开发了萃取回收铜-氧化水解沉淀除铁砷-氟化钠沉淀除钙镁-溶液深度净化-镍萃取反萃-浓缩结晶的全湿法工艺,回收了粗产品中的铜,制备出了电池级硫酸镍,得到了合格的产品。以国产铜萃取剂AD100回收了粗硫酸镍中的铜,在初始pH值为2.0、萃取相比O:A=1:3、AD100体积浓度为15%、萃取时间为5min,常温下经过三级萃取99%以上的铜进入有机相。对负载铜的有机相采用稀硫酸洗涤后进行反萃,以2mol/L的稀硫酸为反萃剂,相比O：A=3：1的条件下,两级反萃可回收99%以上的铜。整个萃取反萃过程铜回收率达98%以上,反萃液可直接进行电积来生产电积铜,电解液实现循环利用。以双氧水为氧化剂,聚合硫酸铁为沉淀剂,碳酸钠为中和剂净化原料中的铁和砷。当双氧水的加入量为26.7mL/L溶液、聚合硫酸铁溶液的加入量为16.7mL/L溶液、反应终点pH值为4.0、反应温度为70℃、反应1h后,铁、砷的沉淀率分别可达99%和99.9%以上,溶液中残余的铁、砷浓度分别低于15mg/L和1mg/L以氟化钠为沉淀剂沉淀分离原料中的钙镁,在终点pH值为5.0、反应温度为90℃、氟化钠过量系数为1.5的条件下反应1h,钙镁的沉淀率分别高于98%和99%,溶液残余钙镁浓度分别低于10mg/L和5mg/L对萃取分离铜-氧化水解沉淀分离铁砷-氟化钠沉淀分离钙镁后的含镍溶液进行了深度净化处理,研究采用P204作为萃取剂在P204皂化率为50%、初始pH值为4.0、相比O：A=1：1、P204体积浓度为20%的条件下萃取10min,六级萃取后萃余液中主要杂质元素Cu、Fe、 Pb、Zn、Mn的含量分别为0.02g/L、0.002g/L、0.001g/L、0.002g/L、0.001g/L和0.002g/L,实现了深度净化的目的。以P204为萃取剂将镍从深度净化后的水相中萃取分离进入有机相,对负载镍的有机相进行反萃便实现了除钠的目的,通过水洗的方法将夹带的少量钠离子进行洗脱,保证了溶液的纯度及产品的质量,并反萃得到了高纯的硫酸镍溶液。最后以此为结晶原液进行浓缩结晶,通过控制浓缩结晶过程各项参数,优化结晶过程得到了符合HG/T2824-2009规定的产品,产品质量达到Ⅱ类优等品要求,可作为电池材料制备用。本研究为实验室规模研究,以此为基础开展的半工业化试验验证了本研究的结论,并为工业化生产的实施提供了理论依据和技术支持。更多还原

【Abstract】 :In this study, crude nickel sulfate which was recovered from copper electro-refining system was taken as the raw material and treat with combined purifying and refining processes so as to obtain refined nickel sulfate with a battery-grade quality. Based on the composition of the raw material, the processes including recovery of copper solvent extraction,iron and arsenic removed by oxidation-hydrolysis-precipitation, calcium and magnesium removed by chemical precipitation and deeply purification by solvent extraction.The impurities in the solution which was obtained by dissolving crude nickel sulfate were removed. Followed with nickel extraction and stripping, a nickel sulfate solution was eventually obtained with high purity. After concentration and crystalizing, the crystalized nickel sulfate was obtained with good quality.Copper was recovered from the crude nickel sulfate solution using efficient extractant AD100. The optimum conditions were:initial pH2.0, phase ratio(O:A)1:3,25%(volume fraction) AD100in the organic phase and the reaction time5min.Over99%of the copper in the solution was transferred into the organic phase with three-stage extraction at room temperature under the above conditions.After stripping of the copper in organic phase with a two-stage extraction using2mol/L of sulfuric acid solution, over99%of copper was stripped into the copper sulfate solution which can be directly electrowining to produce copper powder.The electrowining solution can be recycled after stripping copper from AD100. Recovery of copper was over99%through the extraction and stripping processes.The solution after copper removed was oxidized with hydrogen reoxide precipitated with polymeric and neutralize with sodium carbonate.Iron and arsenic were removed from crude nickel sulfate solution after copper extraction. Optimum conditions were determined when amount of H2O2(30wt.%) was26.7mL/L,d oxidating time was10min,16.7mL/L of polymeric ferric sulfate solution(20wt.%) was added and keep final pH was4.0, reacted1h at70℃, under the above conditions, the content of arsenic in the solution was reduced from1.36g/L to1mg/L the content of iron was reduced from1.36g/L to lOmg/L at the same time, the removal ratio of iron and arsenic were higher than99%and99.9%,respectively.Sodium fluoride was used as precipitant to remove calcium and magnesium from the nickel sulfate solution after to iron and arsenic removed. Under optimum conditions that the reaction temperature was90℃, excessive ratio of sodium fluoride was1.5, final pH was5.0and reaction time was1h, remove rate of calcium and magnesium were over98%and99%,respectively. Concentration of calcium and magnesium remained in the solution were lower than10mg/L and5mg/L respectively.Deeply purification process was followed by removing calcium and magnesium from the nickel sulfate solution. Saponified extractant P204was taken to remove impurities including zinc, manganese, lead and the residual iron and copper in the solution. Optimum conditions were determined by batch experiments. After six-stage extraction under the optimum conditions as:saponification rate of P204was50%, initial pH4.0, phase ratio(O:A)1:1, concentration of P204(volume fraction)20%and reaction time10min, concentration of Cu, Fe, Pb, Zn and Mn remained in the solution was0.002g/L,0.001g/L,0.002g/L,0.001g/L and0.002g/L, respectively. The remained content of the ions as formers showed that the purpose of deeply purification was achieved successfully.After recovered Cu and removed the impurities including Fe, Zn, Pb, Mn, Ca and Mg, P204was adopted as the extractant to separate nickel from the high sodium solution so as to ensure the quality of the products. Nickel was extracted by saponified P204and transferred into the organic phase. Adopting deionized water to wash the organic phase and then stripped nickel with400g/L sulfuric acid solution, nickel sulfate solution with high purity was obtained. By optimizing the Concentration and crystallization processes from the nickel sulfate solution, the crystallized nickel sulfate was filtered out from the mother liquor with the quality of HG/T2028-2009, the component of the product reached the requirement of Ⅱ-level superior products which showed it can be used as the raw material of battery materials.This study was a laboratory-scale experiment. The obtained conclusions were verified by semi-industrial tests based on the above experiment. And, the tests also provided theoretical basis and technical supports with the implementation of industrial production.更多还原