采用EPMA研究硫酸锌溶液中锌粉净化除钴的机理

采用高浓度钴离子的硫酸锌溶液,研究锌粉置换除钴机理,对所得的净化渣进行SEM和EPMA分析.结果表明,温度不同表面沉积物的结构不同,表面沉积物的结构影响置换的速度.温度升高,反应容易进行.通过对产物结构的研究,推测锌粉置换除钴过程的机理为首先是锌粉和钴离子结合形成一种钴-锌合金,这一步反应比较快,然后这种合金继续和钴离子反应得到钴单质,后一步是整个反应的限制步骤.     

新型有机剂净化除钴方法在生产实践中研究与应用

某湿法炼锌厂进行了一种新型有机剂除钴净化方法生产实践研究,经过试验研究及生产实践得知,采用新型有机剂进行净化除钴方法比传统锑盐除钴方法具有优越性,净化控制温度低:75~80℃,时间短,1.5 h,净化后的二段液合格含Co≤1 mg/L,净化后溶液中Co不复溶,二段净化渣量少,渣量仅是传统净化方法产生渣量的1/6,渣含锌少,渣中含钴高,渣中含钴高达4%以上。因此采用新型有机剂除钴净化方法不但能降低生产过程中能耗,减少锌粉单耗,降低锌片加工成本,而且能够有效提高锌冶炼过程中锌的回收率。     

新型有机试剂除钴方法在生产实践中研究与应用

某湿法炼锌厂进行了一种新型有机剂除钴净化方法生产实践研究,经过试验研究及生产实践得知,采用新型有机剂进行净化除钴方法比传统锑盐除钴方法具有优越性,净化控制温度低:75~80℃,时间短,1.5 h,净化后的二段液合格含Co≤1 mg/L,净化后溶液中Co不复溶,二段净化渣量少,渣量仅是传统净化方法产生渣量的1/6,渣含锌少,渣中含钴高,渣中含钴高达4%以上。因此采用新型有机剂除钴净化方法不但能降低生产过程中能耗,减少锌粉单耗,降低锌片加工成本,而且能够有效提高锌冶炼过程中锌的回收率。     

电锌工艺中铜渣除氯应用实践

以锌粉与久置的铜镉渣为原料,利用铜渣除氯原理去除电锌工艺系统中的氯,研究工艺参数对氯脱除率的影响。结果表明,采用硫酸铜溶液和锌粉置换生成的新制活性铜粉进行电锌工艺中铜渣除氯,氯的脱除率达77%～81%,温度影响不大。采用久置铜镉渣洗液提供铜离子,用锌粉置换铜离子生成的活性铜粉进行铜渣除氯时,氯的脱除率随n(Cu)T/n(Cl~-)比值的增大而升高。当n(Cu)T/n(Cl~-)比值从4增加到12时,氯的脱除率从72.66%提高至87.98%。对于久置的铜镉渣制备的铜渣,其中的铜已失去和铜离子、Cl~-反应生成氯化亚铜的活性,因此通过调节温度、pH值、n(Cu)T/n(Cl~-)比值均不能有效地脱除溶液中的Cl~-。     

硫酸锌溶液锌粉逆流置换除镉及直接制备海绵镉

针对硫酸锌溶液采用锌粉置换净化除镉时造成大量锌粉浪费、除镉产物含镉低、后续处理复杂等难题,提出碱度控制与三级逆流锌粉置换新方法,解决产物层包裹和锌粉利用率低的问题,以期能够降低锌粉耗量,缩短镉回收流程,直接制备出海绵镉。考察了锌粉用量、锌粉粒度、净化时间、锌粉添加方式、碱度(BT)值调控等参数对镉脱除率的影响。结果表明：单段除镉的优化条件为温度60℃、搅拌速度150 r/min、锌粉浆化预处理、锌粉用量为理论添加量的1.2倍、反应时间120 min;通过三级逆流锌粉净化除镉,镉的浓度由2.29 g/L降低至0.48 mg/L,镉的脱除率超过99.9%,可实现硫酸锌溶液中镉的深度净化;净化过程可直接产出镉含量为80.5%的海绵镉。研究结果对湿法炼锌净化过程降低锌粉消耗、缩短镉回收流程具有指导意义。     

锌钻异常共沉积机理研究

用电化学方法研究了锌钴异常共沉积机理。实验结果表明，单独电沉积时，在不同电极上，钴离子的沉积电位都比锌离子正１００ｍＶ至２００ｍＶ；当锌钴共沉积时，钴受到抑制，其沉积电位变得比更负。用锑微电极跟踪电极表面附近ｐＨ值发现，钴沉积时，电极表面附近ｐＨ值升高。同时，Ｚｎ＾２＋生成Ｚｎ×２＋生成Ｚｎ（ＯＨ）２，并吸附在电极表面上，阻碍Ｃｏ＾２＋的进一步放电。据此阐明了锌钴异常共沉积机理。     

湿法炼锌中性浸出液分步除铜镉净化新工艺

针对湿法炼锌净化工艺存在效率低、锌粉单耗高、成本高的问题,以锌粉为置换剂,采用分步除铜镉工艺去除湿法炼锌中性浸出液中的铜和镉。在除铜工序,研究了锌粉用量、反应时间、反应温度及搅拌强度等工艺参数对除铜的影响。在深度除镉工序,研究了除镉剂用量、除镉时间、除镉温度及搅拌强度等因素对除镉的影响。结果表明,在优化条件下,中性浸出液经一段除铜镉后,溶液中铜含量小于0.01mg/L、镉含量21.38mg/L,达到了一段除铜镉的技术控制指标,并且显著减少了一段净化的锌粉消耗量,以10万t/a湿法炼锌系统为例,年可节约成本约1 980万元。     

钴在碘—碘化物溶剂中的溶解行为

利用旋转盘技术研究了钴在碘－碘化物溶液中的溶解动力学。所考察的不同参数包括温度、转速、浸出剂浓度和溶液的ｐＨ值。在２￣４２℃的温度范围内，整个溶解反应表现为受限于三碘化物通过扩散边界层的质量转移（阿仑尼乌斯活化能为〈１６．２ｋＪ／ｍｏｌ（４ｃａｌ／ｍｏｌ）。只要溶液的ｐＨ值小于８，那么溶液ｐＨ值的影响就很小。然而，当溶液的ｐＨ值大于８时，由于纯化而使溶解速度明显下降。其溶解速度与作者以前研究的溶解     

利用湿法炼锌铜砷渣进行净化除钴

针对砷盐净化除钴的工艺,以云南某厂的湿法炼锌浸出的中上清液为原料,以湿法炼锌产出铜砷渣作为净化除钴剂,开展了利用湿法炼锌铜砷渣进行净化除钴研究,考察了时间、两段净化除钴和不同添加剂对净化除钴效果的影响。实验结果表明：反应温度95℃,反应时间3h,锌粉3 g.L_^-1,铜砷渣2 g.L_^-1,铜离子400 mg.L_^-1,可将中上清液中的钴含量降低到小于0.01 mg.L_^-1,可以实现深度净化除钴的效果。     

湿法炼锌高钴渣处理工艺研究

采用锌粉置换除钴得到的高钴渣,针对现有工艺的不足,提出了一段硫酸浸出-二段高钴渣中和-过氧化氢氧化除铁-锌粉置换除镉-新型活性硫化剂（简称除镍试剂）除镍-过硫酸钠选择性氧化除锰-过硫酸钠氧化沉钴的湿法冶金工艺,实现渣中钴和镍的分离回收。对工艺流程探究,得出了较优的实验结果。硫酸浓度为150 g/L,温度80℃条件下浸出120min,钴的浸出率为96.14%。锌、镍、镉、铁、锰的浸出率均大于99%。过氧化氢沉铁率达到99.8%以上,过硫酸钠除锰可使锰除到0.13mg/L,沉淀率达到99.98%,Co沉淀率达到99.99%,氧化渣中钴含量达到49.75%。     

Market and recycling of NiMH battery

<正>Market status and future trend of NiMH battery1.Global market of small NiMH battery Global market size of small NiMH batteries declined year on year since 2011.The trend will continue to 2018,at the rate of 5%to 10%annually.Demand for small NiMH batteries will be stable gradually.Many electrical apparatuses are powered by the built-in lithium battery today,which is the main reason for the shrunk market of small NiMH batteries.But,for some products,small NiMH     

China rare earth market review

正September 1-10,2014 Affected by the National Day holiday,rare earth transaction was stagnant and the market showed a weak steady state.As there was no good news for downstream market,some products with flat demand would likely rally slightly for some time to     

Current situation and future trend of China rare earth luminescent material industry

<正>Rare earth luminescent material is one of the most important application sectors of rare earths.China enjoys the exceptional advantage to develop rare earth luminescent material for its abundant rare earth resources.After several decades'endeavor,China's rare earth luminescent material industry,headed by rare earth phosphor for lamp and LED and high efficient rare earth energy-saving light source,has been gradually developed into a scale industry.China has become a major production base of rare earth phosphor for lamps and rare earth     

China rare earth market review

正June 1~10,2014Rare earth market remained weak.Quoted price of rare earth products was similar to that in May.There was no sign of recovery in downstream market.The market of NdFeB magnetic materials and phosphor was depressed.Catalyst,polishing powder and ceramic industries remained inactive.Demand from downstream industry was soft.Consumers purchased on their needs.Suppliers had strong intention to sell.Prices of rare earth products     

2014 second batch of rare earth quota released

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Annual Report analysis of Chinese rare earth-related listed companies in 2013

<正>Chinese rare earth-related listed companies have published their 2013 annual reports.It can be understood from their reports that production and operation activities of Chinese rare earth-related companies were still heavily affected by macro economy and industrial policies.They basically followed the steps of national economy.In 2013,world economy recovered slowly but the economy     

Market opportunities and challenges for rare earth polishing powder

正1.Status of rare earth polishing powder Rare earth polishing powder with high content of cerium oxide began to replace iron oxide for glass polishing and became one of the key materials in glass polishing process since 1940.Compared with traditional iron oxide,rare earth polishing powder has many advantages,such as fast polishing rate,high polishing quality and long service life.It can achieve good surface quality and improve operation conditions.For example,in lens polishing,the polishing work that cerium     

Baotou Research Institute of Rare Earths developed a new RE alloy preparation technology

正Pyrometallurgy Laboratory of Baotou Research Institute of Rare Earths had independently developed a new preparation technology of rare earth alloy for NdFeB.The alloy can remarkably enhance the coercivity of NdFeB magnet but also evidently reduce the production cost of the magnet.The new master alloy was prepared in the kA pilot-scale electrolytic cell by the independent technology.The rare earth master alloy can be used as the raw material for NdFeB.Compared     

China rare earth market review

正November 21~30,2014Due to weak demand from downstream industries,transactions of rare earth in Chinese domestic market were inactive.It was difficult to sell any rare earth products except for dysprosium oxide and terbium oxide.Suppliers lost confidence in recent market.Demand for rare earth products was soft.Consumers continued to take a wait-and-see attitude.Rare earth export market remained slow.     

Galaxy Magnets achieved the net profit of 34.02 million yuan in the first six months of 2014

正Galaxy Magnet announced its financial results for the first half of 2014 on August 14.For the first six months ended on 30 June 2014,Galaxy Magnet achieved operation income of RMB 182.3 million,up8.40% over the same period of 2013,and the net profit attributable to the shareholders of the listed company of 34.02 million yuan,increasing 35.49% over the same period of last year.Stable performance increase was led by development of new customers and application market of magnets.