氟碳铈精矿空气中焙烧的热分解研究

利用ＤＴＡ、ＴＧ、ＸＲＤ及化学分析等方法对山东微山的氟碳铈精矿在空气中焙烧的反应过程进行了研究。指出氟碳铈精矿的分解过程可分为两步，首先较低温度下，（Ｃｅ，Ｌａ）ＣＯ＿３Ｆ氧化分解为（Ｃｅ，Ｌａ）Ｏ＿（１＋ｘ），Ｆ＿（１－ｘ）；随着焙烧温度的提高，（Ｃｅ，Ｌａ）Ｏ＿（１＋ｘ）Ｆ＿（１－ｘ）继续氧化分解，得到Ｃｅ＿（０．７５）Ｎｄ＿（０．２５）Ｏ＿（１．８７５）和Ｌａ＿２Ｏ＿３等，焙烧过程中部分脱氟，样品总失重率达１９．５４％。     

氟碳铈精矿焙烧反应的研究

本文利用ＸＲＤ、ＤＴＡ－ＴＧ及化学分析等方法，对氟碳铈矿的焙烧反应进行了研究。指出氟碳铈精矿在７５０℃下，焙烧５ｈ，分解反应分为两步进行，首先ＲＥＣＯ３Ｆ（本文中ＲＥ代表Ｃｅ、Ｌａ、Ｎｄ、Ｐｒ）分解为ＲＥＯＦ，然后ＲＥＯＦ继续氧化分解得到：Ｃｅ０．７５Ｎｄ０．２５Ｏ１．８７５、ＰｒＯ１．８３、ＬａＦ３等，在焙烧过程中发生部分脱氟，同时铈和镨被部分氧化为四价。同时对焙烧反应动力学进行了计算，得出：反应表观活化能Ｅ＝２２９．７ｋＪ／ｍｏｌ，反应级数ｎ＝０．９５。     

在氟盐体系中镧离子阴极过程的研究

采用循环伏安法研究了ＬａＦ＿３－ＬｉＦ二元熔体及添加Ｌａ＿２（ＣＯ＿３）＿３的ＬａＦ＿３～ＬｉＦ熔体中，９２０～９５０℃下，Ｌａ￣（３＋）在石墨电极上还原的阴极过程。结果表明：在ＬａＦ＿３－ＬｉＦ熔体中，电位在－０．８５Ｖ左右（相对于石墨参比电极），Ｌａ￣（３－）离子在阴极还原析出；在添加Ｌａ＿２（ＣＯ＿３）＿３，的ＬａＦ＿３－ＬｉＦ三元熔体中，Ｌａ（ＣＯ＿３）＿３，分解为Ｌａ＿２Ｏ＿３，Ｌａ＿２Ｏ＿３首先电解，然后ＬａＦ＿３电解，均在阴极上析出镧。镧离子的电化学反应是简单的一步反应，即Ｌａ￣（３＋）＋３ｅ→Ｌａ。     

CaO－MgO_（sat）－FeO_n－SiO_2渣系与铁液间磷平衡分配比的极

按文献［１～４］，Ｌ＿ｐ与（ＦｅＯ＿ｎ）和Ｒ之间均有极值关系存在。本文得出从不同侧面反映的Ｌ＿ｐ极值关系式和曲线：（１）按ＣａＯ／ＳｉＯ＿２＝０～０．９，０．９１～１．９和＞１．９三个区段划分的，用１／Ｔ、ｌｇ｛（ＣａＯ）＋０．７（ｍｇＯ）｝、ｌｇ（ＴＦｅ）和ｌｇ（Ｐ＿２Ｏ＿５）表述的一次多项式；（２）按ＣａＯ／ＳｉＯ＿２＝０～０．０９，０．１～０．９，０．９１～１．４，１．４１～１．９和＞１．９五个区段划分的，用１／Ｔ，（∑ＦｅＯ）、（∑ＦｅＯ）￣２和ｌｇ（１＋ＳｉＯ＿２）表述的非齐次多项式；（３）按∑ＦｅＯ＝１３％～１５％，１６％～２０％和３０％～３５％三个区段描述的Ｌ＿ｐ－Ｒ极值曲线。并发现Ｌ＿ｐ与（∑ＦｅＯ）和Ｒ之间的极值关系存在一定规律。     

溶胶－凝胶法制备La_2Zr_2O_n超微粉末

用溶胶－凝胶法合成了Ｌａ２Ｚｒ２Ｏｎ超微粉末。ＳＥＭ分析表明，Ｌａ２Ｚｒ２Ｏｎ粒子呈球形，平均粒径小于０．５μｍ。Ｘ射线衍射分析表明，在Ｌａ２Ｚｒ２Ｏｎ形成过程中未发现有中间相的存在；焙烧温度８００～９００℃时为荧石结构，１０００℃时为烧绿石结构，属于立方晶系，空间群为Ｆｄ３ｍ（２２７）。晶粒大小计算表明，平均晶粒度随焙烧温度的升高而增大，晶格畸变率则随粒径的增大而变小，红外光谱分析表明，粒子越小，表面活性越高。     

降低Nd_2O_3中杂质Sm_2O_3的工艺研究

在工业生产实践中，对Ｎｄ－Ｓｍ分组采用大捞大洗和加氨水强化萃取分离的工艺方法实现了一步萃取法除去Ｌａ３＋Ｃｅ３＋Ｐｒ３＋Ｎｄ３＋萃余液中Ｓｍ３＋的目的，经六个月运行，产品Ｎｄ２Ｏ３中杂质Ｓｍ２Ｏ３含量稳定在０．０３％以下。     

铁水预处理脱硅对脱磷影响的实验研究

在实验条件下,利用Ｆｅ３Ｏ３－ＣａＯ－ＣａＦ２渣系研究了在高炉铁水预处理过程中脱硅对脱磷的影响。结果表明,在１６２３Ｋ温度下,脱硅渣中ｗ（Ｆｅ２）３）＝１６．８％～４０％进可获得终点ｗ（Ｓｉ）含量为０．１４４％～０．０９０％的脱硅效果;对初始「Ｓｉ」含量小于０．１５％的铁水,在１５７３Ｋ温度下,脱磷渣中ｗ（Ｆｅ２Ｏ３）＝４０％即可获得８５％以上的脱磷率,而在１６２３Ｋ温度下,脱磷渣中ｗ（Ｆｅ２Ｏ３     

西南稀土矿的矿石性质及分选工艺研究

研究了西南稀土矿的矿石性质及分选工艺．原矿风化强烈，产生大约２０％的黑色风化物矿泥。－矿石中可工业利用的稀土赋存形式有矿物相和胶态相。矿物相稀土以氟碳铈矿为主，占９６％以上，重选或重浮选联合工艺可得到ＲＥＯ３０％，５０％和６０％的氟碳铈矿精矿，稀土回收率６５％。胶态相稀土则吸附在Ｆｅ－Ｍｎ非晶质氧化物矿物上，用热盐酸浸出，氨水除杂，草酸沉淀回收稀土，稀土回收率７４．３％，并副产铅。矿石和黑色风化物中稀土都强烈选择铈族稀土，∑ＣｅＯ２在９０％以上，且ＣｅＯ２＞Ｌａ２Ｏ３＞Ｎｄ２Ｏ３。     

混合碳酸稀土热分解过程的研究

用ＤＴＡ热分析技术研究混合碳酸稀土焙烧过程中的脱水过程,分解过程,用Ｆｒｅｅｍａｎ－Ｃａｒｒｏｌｌ法、Ｐｉｌｏｙａｎ法和Ｋｉｓｓｉｎｇｅｒ法对其脱水及热分解的动力学参数进行计算,并对计算的结果进行比较和验证,得到了混合碳稀土脱水过程的反应活化能和反应级数分别为８０６．９Ｊ／ｍｏｌ、０．７８,热分解过程的反应活化能和反应级数分别为８．５２９ｋＪ／ｍｏｌ、０．９５。用ＸＲＤ分析方法研究了不同焙烧温度对焙烧产物的影响,论证高温下焙烧可能产生Ｃｅ０．７５Ｎｄ０．２５Ｏ１．８７５相。     

酸浸闪锌矿过氧化氢除铁方法研究

试验了用控制添加过氧化氢的方法从含硫酸锌和硫酸铁的硫化锌矿酸浸液中分批沉淀针铁矿，发现在ｐＨ＝３．０～４．０，温度为８０℃±，反应Ｆｅ３＋＋３ＯＨ－→ＦｅＯ（ＯＨ）＋Ｈ２Ｏ能较完全地进行，溶液中Ｆｅ离子最终浓度低于５０ｐｐｍ。     

Chinalco Signed Framework Agreement for Strategic Cooperation with Harbin Municipal Government

正Last month,Chinalco signed framework agreement for strategic cooperation with Harbin Municipal Government in Harbin Xiong Weiping,Chairman of Chinalco,said that based on the strategic deployment to build world top-class mining company with the highest growth potential,Chinalco was now concentrating all efforts on making strategic transition and structural adjustment,strategic cooperation with the local governments where     

Jiangxi Promotes Jiangxi Copper Corporation To Become The World's Most Competitive Mining Company

<正>According to the latest info from Jiangxi Province State-owned Assets Supervision and Administration Commission,Jiangxi Copper Corporation was approved to become the first pilot enterprise for deepening reform.Contents of the pilot work is"Three Self"(self expansion,self decision-making,self     

Journal of Rare Earths Contents List of Vol.32(2014)

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Contributions to Baosteel Technical Research wanted

正Baosteel Technical Research,a quarterly journal,which is issued domestically and abroad,is run and sponsored by Baosteel Group Corporation.Baosteel Technical Research mainly reports the achievements in technological innovation,academic research,new product development and industrial equipment improvement by Baosteel.It will continue to follow up on hot topics and serve the company’s technological development and progress.Its readers include experts in     

Ministry of Industry and Information Technology: No Short Term Solution For Our Country’s Excess Nonferrous Metal Smelting Capacity

【正】According to the Ministry of Industry and Information Technology,the Ministry has released the 2013 Operation Report on China’s Industrial Communication Indu...     

Chinalco Signed Framework Agreement for Strategic Cooperation with Gansu Province

正Recently,Chinalco and Gansu Provincial People’s Government signed"Framework Agreement for Strategic Cooperation on Reform,Restructuring and Transition Development of Chinalco’s Electrolytic Aluminum Enterprises in Gansu",signifying that the strategic cooperation between Chinalco and Gansu Province had made new substantive progress.     

Unavoidable Economic Cycle:30% Of Nonferrous Metal Companies Were Involved In Restructuring

正Owing to continual downturn in real estate and bulk commodity markets,a number of traditional industries in China suffered unfavorable impact in performance.With the progressive disclosure of third quarter report,the no-pleasant-surprise performance of     

Baotou Rare Earth Became the World's Biggest High Performance Magnetic Material Base

正The High Performance Magnetic Material Phase II Project,an industry upgrading project implemented by Inner Mongolia Baotou IronSteel Rare Earth(Group)Hi-tech Co.,Ltd,recently basically finished equipment commissioning,signifying that the enterprise had developed the production capacity of15000 t/a Nd-Fe-B strip casting alloy and 5000t/a Nd-Fe-B magnet,thus becoming the world’s     

Introducing Two Central Enterprises to Integrate Rare Earth Industry,Shandong Rare Earth Group Breaks Surface

正With the signing of"Letter of intention for Propelling Integration of Shandong Rare Earth Enterprises"between Shandong Province Commission Of Economy and Informatization,China IronSteel Research Institute Group("China Steel Institute"),and China Rare MetalsRare Earth Co.,Ltd("China Rare Earth"),the"Shandong Rare Earth Group"jointly set up by the 3 units thus broke surface.On August 9,reporters of the China Economic Herald learned from Shandong Province     

Aluminium Production by Province or City in 2014

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