硫酸钙晶须表面湿法改性研究

采用几种表面改性剂对硫酸钙晶须表面进行了湿法改性试验,选出了改性效果较好的硬脂酸对硫酸钙晶须进行了单因素条件改性试验,分别考察了改性剂用量、初始料浆浓度、改性温度、改性时间、搅拌速率、烘干温度、烘干时间等因素对硫酸钙晶须表面改性的影响;改性硫酸钙晶须产品采用活化指数、接触角、扫描电子显微镜、X射线衍射和红外光谱分析进行表征。试验结果表明:硬脂酸对硫酸钙晶须的改性效果较好,在最佳工艺条件下,改性产品的活化指数为1.00,接触角为123.6°。建立了硬脂酸与硫酸钙晶须的作用模型。     

硬脂酸钠对重质碳酸钙的干法改性研究

以咸丰重质碳酸钙为原料,硬脂酸钠为改性剂,采用干法改性制备了改性重质碳酸钙。采用正交试验设计探讨了改性温度、改性剂用量、改性时间和搅拌转速对重质碳酸钙改性效果的影响,利用FT-IR、XRD、SEM、Zeta电位对重质碳酸钙进行表征。结果分析表明,当改性温度为70℃,硬脂酸钠用量为咸丰重质碳酸钙质量的1.5%,改性时间为50min,转速为700r/min时,硬脂酸钠改性咸丰重质碳酸钙的活化率为85.6%,改性效果较好。经过硬脂酸钠改性重质碳酸钙的红外光谱在2 850cm~(-1)和2 920cm~(-1)处出现了-CH_2-对称伸缩振动和反对称伸缩振动峰,X-射线特征衍射峰向高角度偏移,Zeta电位从14.1m V提高到30.2m V,粒径较小,说明硬脂酸钠已接枝到重质碳酸钙表面,但改性并未改变碳酸钙晶型,改性重质碳酸钙具有良好的分散性。     

铝硅酸盐工业废渣表面改性工艺研究

以铝硅酸盐工业废渣为原料 ,分别进行了表面活性剂、偶联剂单一表面改性和复合表面改性试验研究。结果表明 ,KH- 5 6 0硅烷偶联剂与硬脂酸复合改性处理效果最佳。其工艺条件为 :偶联剂用量 0 .2 %～ 0 .5 % ,硬脂酸用量 2 %～ 4 % ,改性时间 30～ 5 0 min,搅拌速度 95 0 r/ mi     

哈密硅灰石表面改性、表征及其在防火涂料中的应用

以新疆哈密硅灰石为原料,采用硬脂酸进行表面改性研究表明,当硬脂酸用量1.0%.改性时间15min,改性温度65℃,矿浆浓度为40%时.硅灰石表面改性效果最好,红外图谱表明,硬脂酸在硅灰石表面产生化学吸附和化学键合作用.扫描电镜照片表明.硅灰石原矿粒子表面上存着很多不平的硅灰石微粒,而改性硅灰石粒子表面看到物质包覆沉积、改性硅灰石应用于防火涂料中,测试结果完全符合其国家标准质量指标要求,因此可用于防火涂料并替代40%～60%的钛白粉填料,从而降低其生产成本.     

硅烷偶联剂KH570对石英砂的表面改性工艺研究

以石英矿为改性原料,选用硅烷偶联剂KH570为改性剂,分别采用干法工艺和湿法工艺对石英砂粉体进行表面改性.得出干法改性最优条件为:硅烷偶联剂KH570水解配比为KH570、乙醇与水质量比1∶10∶1,改性剂用量1.2％,改性时间80 min;湿法改性最优工艺条件为:改性剂用量5.0％,改性温度70℃,改性时间100 min.红外光谱和扫描电镜分析表明,硅烷偶联剂KH570包覆在石英砂表面,改性后石英砂分散性得到了很好改善,湿法改性效果优于干法改性.     

重晶石矿粉表面改性研究

利用硬脂酸、硅烷偶联剂对重晶石粉进行了表面改性.结果表明,改性时间、改性温度和改性剂用量等因素对改性效果有重要影响.经活化指数测定,改性后的重晶石矿物表面的疏水性得到了明显改善;红外光谱分析表明,重晶石矿粉表面确实已经包覆了改性剂.     

凹土的表面改性及其在雨靴面胶中的应用

用硬脂酸对凹凸棒石黏土 (凹土 )进行改性 ,改性的最佳条件为硬脂酸用量为 2 %、改性温度为 80℃、改性时间为 3 0min ,所得改性凹土的活化指数达 0 .95。改性凹土在雨靴面胶中的填充试验表明 ,改性凹土可以完全替代轻钙。     

纳米碳酸钙表面改性研究

采用硬脂酸对纳米碳酸钙进行改性,并对改性产品进行了表征。硬脂酸湿法改性纳米碳酸钙的最佳条件为硬脂酸用量为2 5%,料浆浓度为9%,改性温度为90℃,改性时间为40min,搅拌速率为2500r/min,烘干温度为100℃;所得改性纳米碳酸钙产品的活化指数达0 94以上,白度在96%以上。活化指数测定结果表明,改性后的纳米碳酸钙由亲水疏油性变成了亲油疏水性;IR分析表明硬脂酸与纳米碳酸钙以化学键结合。     

电气石的表面改性研究

采用硬脂酸对电气石进行表面改性，研究了温度、时间和改性剂添加量等因素对电气石改性效果的影响。用活化指数和IR对改性前后的电气石进行了表征及机理分析。结果表明：硬脂酸与电气石表面发生了化学吸附，用硬脂酸对电气石改性过程温度低．作用时间短、改性效果好．药剂成本低，有很好的应用前景。     

硬脂酸改性氢氧化镁及表征

使用硬脂酸对氢氧化镁进行表面改性,研究了改性剂用量、改性温度和改性时间等因素对氢氧化镁表面改性的影响。在硬脂酸用量5%,改性温度70℃,改性时间90min,Mg(OH)2浆料浓度10%,转速1 000r/min的条件下制备的产品性能优良,活化指数达99.8%。使用粒度分析、粘度分析、红外光谱和热分析对产物进行了详细的表征,结果表明:氢氧化镁经硬脂酸改性后,粒度由9.83μm降至8.73μm,在液体石蜡中的粘度较改性前明显降低,硬脂酸分子在氢氧化镁表面发生吸附键合,形成硬脂酸盐,其化学组成为9CH3C16H32COOMgOH·(CH3C16H32COO)2Mg。     

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