硅铝酸钠溶液性质的研究

通过对铝酸钠和硅铝酸钠溶液的红外光谱、粘度、丁达尔效应、聚沉实验测定和分析，得出结论：αk=1．52时，p(Al2O3)=100、150、200g／L含硅铝酸钠溶液中存在大体积的铝酸根和硅铝酸根阴离子群。在αk=1．52时，р(Al2O3)=100g／L、р(SiO2)=3g／L，р(Al2O3)=150g／L、р(SiO2)=5g/L，р(Al2O3)=200g/L、р(SiO2)=11g／L的硅铝酸钠溶液中有纳米级的胶性基元，属于无机高分子溶液。     

白云石为钙镁源合成六铝酸钙和尖晶石的研究

本文以白云石[CaMg(CO3)2]和Al(OH)3为原料合成六铝酸钙(CA6)和尖晶石(MgAl2O4),分析了不同原料配比对试样的物相组成和显微形貌影响。研究结果表明:以白云石和Al(OH)3在1 550℃保温3h可以合成CA6和MgAl2O4;在该温度条件下不同白云石和Al(OH)3摩尔配比的5组试样烧结后的主要物相为CA6及MgAl2O4,六铝酸钙呈现片晶状,尖晶石呈细小颗粒状。     

Zr/Al基累托石矿物材料的研究

在室温条件下,用取代法和共聚法配制了稳定的Zr/Al二元聚合阳离子,稀溶液法制备Zr/Al基柱撑累托石矿物材料,XRD和FTIR表征Zr/Al基柱撑累托石室温下和300℃、500℃下晶体结构的变化,得出Zr/Al基柱撑累托石矿物材料的热稳定性达到500℃以上,Zr/Al二元聚合阳离子和累托石Si-O层发生了化学键合,形成了[Si-O]-[H(O)-Al(Zr)]键.EMPA分析,当Zr/Al=11时,柱撑累托石中ZrO2的百分含量为5%～6%,Zr4+进入到铝聚合阳离子中,形成了[AlO4(Zr,Al)12(OH)24(OH2)12]7+聚合阳离子.     

无机盐杂质对铝酸钠溶液晶种分解率的影响

采用对比实验法,研究了不同类型、不同浓度的无机盐杂质对铝酸钠溶液晶种分解的影响,并探讨了其影响机理。结果表明,铝酸钠溶液中氯化钠、碳酸钠、硫酸钠等杂质的存在对晶种分解会产生不利影响,当NaC l浓度大于10 g/L、Na2Os浓度大于5g/L、Na2Oc浓度大于10 g/L时,均将对铝酸钠溶液晶种分解产生明显的抑制作用。无机盐杂质的存在会影响铝酸钠溶液中氢氧化铝颗粒表面的Zeta电位值,使Zeta电位变得更负,不利于氢氧化铝晶体颗粒对铝酸根离子的吸附,从而对铝酸钠溶液晶种分解产生抑制作用。无机盐杂质使铝酸钠溶液表面张力增大,也阻碍铝酸根离子在晶体表面的吸附,对晶种分解产生不利影响。     

中高浓度铝酸钠溶液一段脱硅的动力学研究

本文主要考察脱硅时间、脱硅温度对铝酸钠溶液脱硅动力学影响,得到铝酸钠溶液一段脱硅的动力学方程为：-dC/dt=2.22?108exp(-44.9?103/RT)C1.65;此过程的活化能为44.9kJ/mol,反应级数为n=1.65。硅渣的XRD结果表明：当硅铝酸钠溶液中Al2O3浓度为170g/L、苛性比为αk=1.5、硅含量为8g/L、脱硅剂的用量为27g/ L 、脱硅时搅拌速度为300 r/ min时,升高反应温度或延长反应时间,衍射峰逐渐增强,均有利于铝酸钠溶液脱硅反应的进行,最佳反应时间为90 min、最佳反应温度为90℃。     

伟晶岩型铝硅酸盐矿物的晶体化学特征计算与分析

探讨了伟晶岩型铝硅酸盐矿物(锂辉石、长石和云母)的晶体结构,三者晶体结构最大不同之处在于Al—O配位方式不同。其中,锂辉石晶体结构中Al在硅氧四面体骨干之外,以六配位的形式组成[AlO_6]八面体;钠长石晶体结构中Al取代了Si呈[AlO_4]四面体;而白云母晶体结构中[AlO_4]四面体和[AlO_6]八面体同时存在。同时,以键价的观点对这三种矿物晶体结构中化学键的特征进行理论计算。结果发现,M~(n+)静电价强度、M~(n+)—O~(2-)键平均键长、库仑力、平均键价之间具有极好的一致性。在伟晶岩型铝硅酸盐矿物结构中,[SiO_4]四面体Si—O键是最强的,当Al取代Si时,[AlO_4]四面体中Al—O键的键强次之,[AlO_6]八面体Al—O键的键强较弱,其它金属M—O键的键强最弱。     

硅酸钠溶液水热法深度脱铝过程研究

以Na_2SiO_3·9H_2O、NaAlO_2和CaCl_2为原料,采用水热法将溶液中的铝转化成水化石榴石沉淀进行脱铝。通过对水热温度160℃、时间1～16h条件下得到的粉体进行X射线衍射和扫描电镜分析,得到硅酸钠溶液深度脱铝的最佳条件。结果表明,水热1h,反应体系中Ca_5Si_6O_(16)(OH)_2、Ca_5Si_6O_(16)(OH)_2·8H_2O和低铝水化石榴石Ca_5Si_5Al(OH)O_(17)·5H_2O絮状混合沉淀大量生成;当水热时间为10～12h时,体系中同时存在高铝水化石榴石Ca_(2.93)Al_(1.97)Si_(0.64)O_(2.56)(OH)_(9.44)与低铝水化石榴石Ca_5Si_5Al(OH)O_17·5H_2O物相,铝脱除率可达98.05%,可实现反应体系的深度脱铝。     

硅酸钠溶液水热法深度脱铝研究

以Na_2SiO_3·9H_2O、NaAlO_2和CaCl_2为原料,采用水热法将溶液中的铝转化成水化石榴石沉淀进行脱铝。通过对水热温度160℃、时间1～16h条件下得到的粉体进行X射线衍射和扫描电镜分析,得到硅酸钠溶液深度脱铝的最佳条件。结果表明,水热1h,反应体系中Ca_5Si_6O_(16)(OH)_2、Ca_5Si_6O_(16)(OH)_2·8H_2O和低铝水化石榴石Ca_5Si_5Al(OH)O_(17)·5H_2O絮状混合沉淀大量生成;当水热时间为10～12h时,体系中同时存在高铝水化石榴石Ca_(2.93)Al_(1.97)Si_(0.64)O_(2.56)(OH)_(9.44)与低铝水化石榴石Ca_5Si_5Al(OH)O_17·5H_2O物相,铝脱除率可达98.05%,可实现反应体系的深度脱铝。     

铝酸钠溶液表面张力的化工数学模型

采用正交实验方法研究铝酸钠溶液的表面张力数学模型。结果表明，Na2O浓度和温度对溶液表面张力的影响显著。Al2O3浓度影响不显著，交互相和二次相的影响可以忽略。溶液表面张力随Na2O和Al2O3浓度增加而增加。随温度升高而降低。数学模型在试验区拟合很好，由数学模型计算得出的表面张力与实际测量值偏差较小。可以满足氧化铝生产的实际需要。     

硼酸镧/铟复合纳米微粒在菜籽油中的摩擦学性能

用化学反应法制备了纳米硼酸镧,与纳米铟共混形成La2[B4O5(OH)4]3/In复合纳米微粒,用XRD、EDS对其物相组成及结构进行表征,利用四球试验机考察了不同复配比的La2[B4O5(OH)4]3/In复合纳米微粒在菜籽油中的摩擦学性能。通过SEM、XPS等手段,分析了磨损表面的形貌、元素组成和典型元素的化学状态,探讨La2[B4O5(OH)4]3/In复合纳米微粒润滑体系的作用机理。结果表明：复合纳米微粒由无定形水合La2[B4O5(OH)4]3和体心四方相结构纳米In组成。当水合La2[B4O5(OH)4]3与In质量配比为7∶3复合时,该润滑分散体系的减摩抗磨性能最佳,比纯菜籽油润滑的摩擦因数和磨斑直径分别降低51.2%和40.2%。主要是由于复合纳米微粒在磨损表面形成了以化学键、金属键结合为主吸附为次的自修复膜,使表面性能得到优化,提高了减摩性,同时补偿了磨损量,抗磨性也得到明显提高。     

China rare earth market review

正November 1~10,2014Chinese rare earth market was still inactive.Demand for rare earth products was weak.Consumers took a wait-and-see attitude for lower price.As it was an off season for rare earth products,it was expected that prices of rare earth could continue turbulence at the bottom in short terms.Due to a sharp drop,demand for rare earth from downstream recovered.Affected by new energy vehicles,wind powder and energy-efficient appliances,production of rare earth permanent     

China rare earth market review

正August 1~10,2014 There was some good news in rare earth industry recently.Restructuring plans of rare earth groups led by Baotou IronSteel Group and Xiamen Tungsten Group respectively have been approved by MIIT.And rare earth storage policy,which had been expected for a very long time,has been launched officially.Pushed by the good news,rare earth price started to rebound since August 5.Price of didymium oxide and dysprosium oxide rose about 1% to 2%,averagely.About 10% of     

China rare earth market review

正July 1~10,2014Due to weak demand from downstream industry and slow transactions,rare earth market remained weak and price of rare earth products continued to decline.There was no sign of recovery in downstream market.The market of NdFeB magnetic materials and phosphor was depressed.Catalyst,     

New energy vehicle:an opportunity for rare earth magnets

<正>Extracted from Securities Guide 1.Popularity of new energy vehicles—an irresistible market trend1.1 Progress of new energy vehicles Chinese Premier Li Keqiang said recently on a visit to Xi'an BYD Autos that new energy vehicles,especially new energy bus,can lessen environment and noise pollution.He encouraged the use of new     

注浆加固技术在十三矿-685 m进风大巷中的应用

针对煤矿开采深度不断向深部延伸,掘进巷道受深部高应力的影响越来越大,巷道围岩整体稳定性差,矿山压力显现越剧烈现象,一般锚网喷加锚索支护无法从根本上控制巷道的变形。总结了平煤股份十三矿-685 m进风大巷注浆加固技术,依据对巷道掘进之后变形监测数据的采集,对巷道变形机理进行分析研究,并对注浆时段进行了合理选择,在对巷道的注浆工艺进行了充分论证的基础上,对巷道进行了注浆。注浆后效果表明:巷道滞后注浆时间段的选择非常重要,巷道在恰当的时间内进行注浆加固施工,能有效控制巷道的变形,巷道注浆后变形量明显减小,岩体的稳定性明显增强,减少了巷道日常维修工作,降低了矿井的生产成本,保障了矿井的安全生产。     

Brief news

正China Minmetals Rare Earth Construction of Jianghua Separation Plant is set to complete at the yearend Civil works of Jianghua Separation Plant have been finished and the company is installing and debugging equipments now.It is estimated that construction of Jianghua Separation Plant will be     

Brief news

正Total transactions of rare earth in Rare Earth Ex-change Center of Hunan South Rare and Precious Metal Exchange neared 40 billion yuan from January to October From the opening in January of this year to the end of October,the total transaction of rare earth products in Rare Earth Exchange Center of Hunan South Rare and Precious Metal Exchange neared40 billion yuan.There are 16 varieties including dysprosium oxide and terbium oxide traded on the exchange center,one of the largest trading platforms for rare earth oxides in China.     

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