三价铬在ChCl/CrCl3·6H2O体系中的电沉积机理

采用循环伏安法、恒电流阶跃电位-时间暂态曲线研究Cr(Ⅲ)在ChCl/CrCl3·6H2O体系中的电化学行为.计时电位法计算得到333K下的扩散系数4.504×10(-10)cm2/s.循环伏安法得到电化学反应的表观活化能约为40kJ/mol.研究表明,在ChCl/CrCl3·6H2O体系中Cr(Ⅲ)还原为金属Cr是单步骤受扩散控制的完全不可逆过程.Cr(Ⅲ)在还原过程中无前置化学反应存在.     

铁基镍铬合金膜电解工艺的研究

在盐酸体系中采用膜电解电溶法处理含镍、铬的铁基高温合金。通过优化条件, 确定了膜电解过程的操作条件。研究结果表明, 在电压为1.5 V、平均电流密度为500 A/m²、Ni²⁺离子浓度为1 mol/L、阳极液酸度为1 mol/L、极距为20 mm、温度为35 ℃条件下电解, 电流效率可达90%以上, 能耗为1 200 kW·h/t左右。     

废镍合金的电化学溶解研究

采用电化学溶解法对含Co、Cu、Fe 等杂质的废镍合金在硫酸中的溶解过程进行了研究。采用EDTA 络合滴定法分析和原子吸收分光光度法测定了溶液中镍及杂质金属离子的含量。研究了电流密度、硫酸浓度、电解液温度、电解时间及电解方式等对电化学溶解的影响。得到废镍合金电化学溶解的优化工艺条件为:阳极电流密度200 A/m²、硫酸浓度1.25 mol/L、温度40 ℃, 采用方波脉冲电流电解。稳定电化学溶解时的主要技术指标为:槽电压0.8～1.0 V, 电流效率90.8%, 每吨镍直流单耗为800～1015 kW·h 。     

PbS-NaCl-KCl熔体电解中反电动势的研究

采用连续脉冲—微机函数仪法研究了PbS在NaCl—KCl熔体中的反电动势,发现在0～3A/cm~2区间有3个平台,电位分别为0.5～0.7V,1.2～1.5V和3.2～3.5V。故认为当i<0.3A/cm~2时为PbS的直接电解,而在i>0.5A/cm~2时为钠还原。     

低能耗熔盐电解金属锂电解槽的开发及研究

近年来,金属锂在全固态锂电池、铝锂合金制备中发挥着不可替代的价值,但金属锂生产成本仍然是生产企业需要解决的问题。因此,从降低能耗角度优化生产工艺及设备角度利用Solid Works三维建模电解槽结构,以及ANSYS仿真模拟软件对电解槽进行热场模拟及计算,得出最优设计方案。生产电解效率可达到91%,能耗在35 kWh/kg以下,抽氯和集锂装置可以自动运行,抽出氯气浓度90%,集锂效率可达到80%以上,且出锂量较为稳定。该设备可以更好的投入产业化生产,满足企业降低生产成本的需要,促进熔盐电解金属锂行业的发展。     

氯化物体系中镍阴极还原电化学行为

通过极化测量,对氯化物体系中镍阴极还原电化学行为进行研究,系统探讨了溶液中总镍浓度、氧化铵含量、氯化钠含量、硼酸浓度、电解液ＰＨ值及等工艺条件对阴极还原的影响,分析了镍阴极还原电化学行为变化的原因。本研究对氯化物体系中电解沉积镍粉具有指导作用。     

控制电位氯气浸出高冰镍动力学研究

研究了60—100℃的温度范围内在CuCl_2-NaCl体系中控制电位氯气浸出高冰镍的动力学。实验结果表明,该浸出过程很近似地符合有副反应或中间产物对主反应速率过程产生影响的数学模型。实验研究了反应温度、初始铜离子浓度、浸出电位、颗粒粒径等因素对浸出过程的影响,发现一定浸出电位下,浸出速率主要取决于反应温度和溶液初始铜离子浓度。反应的表观活化能为93.34kJ/mol,表明浸出反应速度是由化学反应控制。用电化学机理能较好地解释浸出过程反应机理。     

低共熔溶剂中电解分离高铅锑合金制备高纯锑粉

提出了一种在氯化胆碱—乙二醇低共熔溶剂(ChCl-EG DES)中电解分离高铅锑合金制备高纯锑粉的新方法。测试了343K下SbCl_3浓度对SbCl_3+ChCl-EG DES的黏度和电导率的影响。发现随着SbCl_3浓度的升高,SbCl_3+ChCl-EG DES的黏度逐渐增大,电导率反之。采用线性扫描伏安法研究了金属锑和金属铅在SbCl_3+ChCl-EG DES中的阳极溶解行为。结果表明,锑和铅的氧化电位均为0V左右,当SbCl_3浓度从0.05mol/L升高到0.25mol/L时,有利于高铅锑合金的电解分离。电解实验表明,在343K下,当SbCl_3浓度为0.15mol/L时,可获得团聚且不规则的锑粉,其纯度高达99.980%,电流效率为93.57%,电能单耗为749.18kW·h/t。     

温度对钢筋混凝土中氯离子含量测定的Ag/AgCl电极影响研究

根据能斯特方程,在其它条件不变的情况下,Ag/AgCl电极的电位是温度的函数。为研究温度对Ag/AgCl电极的影响,将Ag/AgCl电极放在不同浓度Na Cl溶液(0.001、0.01、0.1、0.5、1mol/L)中进行不同温度(5、15、25、35、45、55、65℃)的恒温水浴加热,进而研究Ag/AgCl在不同温度下的电位变化。结果表明:Ag/AgCl电位随温度变化不大,温度的变化对电极电位的影响较小;Na Cl浓度由大到小但对应的温度系数均较小,可忽略温度对Ag/AgCl干扰的影响。     

Zr(IV)在NaCl-KCl-K2ZrF6熔盐体系中的电结晶机理

熔盐电解精炼法是乏燃料后处理的一种重要方法,电沉积和结晶机理研究对U、Zr等金属分别回收具有重要意义。在高温熔盐三电极体系下,以铂丝作为研究电极、热解石墨坩埚作辅助电极、Ag/AgCl作为参比电极,采用循环伏安法和计时电流法开展研究。研究了温度为1023 K时Zr(IV)在NaCl-KCl-K2ZrF6熔盐体系中的电结晶成核机理,通过电化学理论分析和恒电位电解产物微观形貌分析得到锆晶核在铂电极上的成核机理为连续成核,成核长大机理为扩散控制的三维半球形螺旋生长机理。为电解精炼提纯金属锆以及乏燃料后处理的研究提供一定的参考。     

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     

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     

矿用防爆轴流对旋主要通风机叶片ANSYS模态分析及应用

高效节能矿用防爆对旋主要通风机的叶片是主要通风机运行的关键部件,叶片在运行时不断受到气流的作用力,从而使叶片产生振动,当叶片振动的频率与叶片的固有频率接近时,容易产生共振从而导致叶片的断裂。一旦叶片断裂时,对主要通风机的安全运行产生致命的影响,从而导致矿山、化工等企业发生重大事故,将会产生不可估量的损失。基于有限元分析软件ANSYS,对高效节能矿用防爆轴流对旋主要通风机叶片进行模态分析及产生对应的六阶模态频率,对主要通风机叶片的运行频率、固有频率及产生的共振问题进行了原理分析,并且解决了叶片频率共振的问题,从而为主要通风机叶片结构设计提供理论依据,并对主要通风机叶片的安全运行提供保障。     

2013 NdFeB export analysis

<正>China totally exported nearly 24,000 tonsof NdFeB products during 201 3,including 18,825 tons of permanent magnet,valued USD 1.34 billion at an average price of 71.4 USD/kg;3,277 tons of NdFeB magnetic powder,valued USD 1 01 million at an average price of 30.9 USD/kg;1,334 tons of strip casting ribbon,with total export value of USD 74million at an average price of 55.3 USD/kg;and 586     

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     

唐口煤矿深部复杂开采工作面瓦斯分源涌出规律研究

研究工作面瓦斯涌出规律对工作面瓦斯治理有重要意义。为了得到唐口煤矿深部3号煤层复杂开采条件下工作面回采时期瓦斯涌出时空演化规律,选取6304工作面作为对象,采用实测方法研究6304工作面瓦斯涌出规律。结果表明:6304工作面瓦斯涌出量为6.534 m³/min,其中煤壁占34.27%,落煤占29.62%,采空区占36.11%;沿工作面倾向由低到高,瓦斯浓度整体为上升趋势,其中1—76号架工作面瓦斯浓度小于0.20%,76—102号架瓦斯浓度上升明显,最大为0.387%;上隅角的后部采空区是工作面的瓦斯主要涌出源,上隅角1号测点瓦斯浓度0.78%,上隅角周边3号、5号、7号、8号、9号测点瓦斯浓度平均为0.643%;周期来压时,上隅角瓦斯相对平时较高。研究为针对性的瓦斯分源监控与灾害防治提供基础。