硅藻土微波酸浸提纯工艺研究

针对硅藻土酸浸提纯的工艺要求和微波作用的特点，将微波技术引入硅藻土提纯，提出了硅藻土微波预处理提纯工艺和微波酸浸提纯工艺。实验研究结果表明，微波可强化硅藻土的酸浸提纯。     

加压碱浸——常压酸浸提纯隐晶质石墨工艺

针对现有石墨提纯技术的不足,提出加压碱浸—常压酸浸工艺,考察了加压碱浸和常压酸浸各因素对提纯效果的影响。结果表明,在加压碱浸温度200℃、碱浓度250g/L、液固比3、反应时间1h、矿石粒度P90=-45μm,常压酸浸温度80℃、酸浓度2.16%条件下,提纯后石墨产品固定碳含量可达96%以上。     

加压碱浸-常压酸浸提纯隐晶质石墨工艺研究

针对现有石墨提纯技术的不足,提出加压碱浸—常压酸浸工艺,考察了加压碱浸和常压酸浸各因素对提纯效果的影响。结果表明,在加压碱浸温度200℃、碱浓度250g/L、液固比3、反应时间1h、矿石粒度P90=-45μm,常压酸浸温度80℃、酸浓度2.16%条件下,提纯后石墨产品固定碳含量可达96%以上。     

我国粘土质硅藻土矿的提纯研究

本文论述了我国粘土质硅藻土矿或含粘土等杂质较多的硅藻土矿的提纯试验研究成果，归纳总结了酸浸，选矿，干法重力层析等方法及工艺流程。     

微波作用下硅藻土酸浸除铁过程研究

研究在微波作用下硅藻土酸浸除铁过程的影响因素和工艺条件。结果表明。硫酸浓度、微波功率和浸出时间对硅藻土除铁均有影响，浸出时间是影响浸出的最主要因素，微波功率和硫酸浓度次之。随浸出时间延长。微波功率增加，硫酸浓度加大，硅藻土中的Fe2O3含量减少。Fe2O3浸出率增加。在试验条件下。较佳的工艺条件为硫酸浓度40％，浸出时间45min，微波功率260W。在此条件下获得的硅藻土产品指标为SiO283．50％，Al2O37．18％，Fe2O30．87％，达到了硅藻土助滤剂质量标准SiO2〉80％，Al2O3〈10％。Fe2O3〈2％。     

硅藻精土酸浸-煅烧增白工艺与性能表征

以经过物理选矿处理后的硅藻精土为原料,采用硫酸酸浸和煅烧进行增白工艺研究。探讨了酸浸温度、酸浸时间、硫酸浓度、液固比对硅藻土增白效果的影响,并对酸浸增白硅藻土样品的白度、化学成分、矿物成分及颗粒形貌等进行了表征。结果表明,硅藻土酸浸增白的适宜工艺条件是:酸浸温度98℃、酸浸时间4 h、硫酸浓度5 mol/L、液固比2.5∶1(m L/g)、煅烧温度600℃、煅烧时间2 h;酸浸处理能有效去除黏土类矿物和石英、长石等杂质,煅烧能有效去除有机质;经过增白处理,硅藻土白度从41.8%提高到80.6%,二氧化硅含量从82.11%提高到93.78%。     

硫铁矿还原浸出半氧化锰矿的工艺研究

以半氧化锰矿为研究对象, 采用硫铁矿还原酸浸工艺浸出其中的锰。利用正交和单因素实验考察了硫酸浓度、硫铁矿用量、反应时间和反应温度对锰浸出率的影响, 结果表明, 各因素影响锰浸出率的大小顺序为:硫铁矿用量>硫酸浓度>反应时间>反应温度, 较优工艺条件为:硫酸浓度3.0 mol/L, 硫铁矿与半氧化锰矿质量比为0.2, 反应时间2 h, 反应温度85 ℃, 液固比为3∶1, 在此条件下, 半氧化锰矿中锰浸出率达92%。     

微波作用下硅藻土提纯研究

根据热力学理论探讨了微波加快化学反应速率的机理。研究了微波作用下硅藻土提纯的影响因素和工艺条件，研究结果表明：随着浸出时间的延长，微波功率的增加，硫酸浓度的加大，硅藻土中的Fe2O3含量减少，Fe2O3浸出率增加。     

利用油页岩渣制备氧化铝和白炭黑

以油页岩渣为原料, 分别用酸浸法和碱溶法制备了氧化铝和白炭黑。讨论了焙烧活化作用、酸浸温度、盐酸用量以及酸浸时间等对氧化铝提取率的影响。实验结果表明, 油页岩渣不需活化可以直接采用酸浸法制备氧化铝,最佳工艺条件为: 酸浸温度100 ℃、酸浸时间2.0 h、盐酸/油页岩＝40.0 mL/15.0 g; 氧化铝提取率为90.6%, 纯度为91.7%。探讨了反应温度、反应时间以及碱浓度等对白炭黑提取率的影响,最佳工艺条件为: 反应温度100 ℃、反应时间6.0 h、NaOH浓度为6 mol/L; 白炭黑提取率为80.5%, 纯度为95.9%。灰渣剩余量不到原来的5%, 达到了油页岩渣生态化利用的目的。     

大田细鳞片石墨的提纯试验研究

以福建大田县产细鳞片石墨(含碳量为90.94%)为原料,采用碱酸法时其进行提纯实验研究,并分析了各工艺因素对提纯效果的影响.最佳工艺条件为:碱熔过程中焙烧温度600℃,时间90rain,NaOH溶液浓度38%,NaOH/石墨质量比26.8%;酸浸过程中酸浸温度70℃,酸浸时间120min,盐酸浓度10%,HCI/石墨质量比3.84,在此条件下所制得的石墨固定碳含量达到98.74%.     

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     

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     

2014 second batch of rare earth quota released

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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