真空蒸馏-籽晶定向凝固工艺制备半导体用高纯铟

采用真空蒸馏-籽晶定向凝固工艺制备6N及以上高纯铟,考察了蒸馏温度、凝固速度及凝固次数对杂质脱除率的影响,并对半导体用高纯铟进行了表面分析及其纯度测定。结果表明,真空蒸馏温度1 273 K、保温时间60 min、定向凝固温度150~170 ℃、籽晶转速5 r/min、坩埚转速15 r/min、凝固速度20 mm/h、凝固次数3次条件下,高纯铟产品纯度达到6N及以上超高纯铟标准,该工艺所得金属铟结晶度高,呈现出片状结构,金属呈单晶相,实现了6N及以上金属铟的稳定结晶,并且金属铟没有腐蚀和表面氧化,该半导体用高纯铟制备工艺所得产品纯度高、制备过程能耗低和效率高,利于实现产业化。     

真空蒸馏法制备高纯金属钙的热力学及工艺研究

对真空蒸馏法制备高纯金属钙的热力学及动力学进行了详细的计算,对预蒸馏及蒸馏分别进行试验研究,优化了高纯钙真空蒸馏提纯工艺。确定了预蒸馏温度700℃,预蒸馏时间40 min;蒸馏温度850℃,蒸馏时间60 min。同时,研究发现不锈钢蒸馏装置内壁镀铬能有效的防止蒸馏装置材质对蒸馏产物的污染,经过一次蒸馏即可获得纯度高达99.998%的高纯金属钙。     

非高纯氧化钪制备高纯无水氯化钪熔盐的试验

采用惰性气体气流中一步快速升温脱除氯化铵和剩余结晶水工艺,利用非高纯氧化钪制备高纯无水氯化钪熔盐。工艺条件的影响试验结果表明:在脱氯化铵和剩余结晶水阶段温度为400℃、保温时间为120min、升温速度为11℃/min、氯化铵与氧化钪重量比=1.8:1、氧化钪与辅盐重量比=1:5、惰性气体流量为6.0L/min的综合工艺条件下,高纯无水氯化钪熔盐中钪的水解率为1.95%。扫描电镜形貌及电子探针微区成分分析表明,高纯无水氯化钪熔盐结晶状态较好,其他杂质元素的含量较低。     

真空蒸馏法制备高纯镁的热力学及工艺

本文对工业金属镁的真空蒸馏提纯效果及相关热力学数据进行了理论分析与计算,并在自行设计制作的蒸馏塔中进行了真空蒸馏实验研究。研究表明,控制蒸馏塔上、中、下三段的温度分别为450℃、650℃和700℃时,产物高纯镁的分布较为集中,几乎全部凝结在冷凝塔中间部位塔盘上,且蒸出率高达94.5%,经过一次蒸馏即可获得纯度高达99.9995%的高纯金属镁。     

真空蒸馏法制备高纯镁

在热力学分析的基础上研究工业金属镁的真空蒸馏提纯过程。结果表明,控制蒸馏塔上、中、下三段的温度分别为450、650和700℃时,产物高纯镁的分布较为集中,几乎全部凝结在冷凝塔中间部位塔盘上,蒸出率高达94.5%,经过一次蒸馏即可获得纯度高达99.9995%的高纯金属镁。     

干法制备无水氯化铈的研究

采用氯化铵和氧化铈为原料,利用自制成套氯化装置干法制备无水氯化铈,实现了无水氯化铈的批量生产。扩大试验结果表明:在氧化铈50 kg,氯化铵用量为理论量的2.4倍,均匀混料,反应温度450℃,反应时间32 h,料层厚度15 cm的条件下产品无水氯化铈纯度可高达99.35%。     

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。     

铟-锡合金真空蒸馏气-液平衡研究

在系统压力5 Pa～10 Pa、蒸馏温度1470 K～1570 K条件下,开展了铟-锡（In-Sn）二元合金真空蒸馏实验研究,结果表明随着蒸馏温度升高,液相中In含量从14.31 wt. %降至0.01 wt. %,表明真空蒸馏可有效分离In-Sn合金。采用分子相互作用体积模型（MIVM）计算In-Sn合金组元的活度,计算值与实验值的平均标准偏差分别为±0.0113、±0.0154,平均相对偏差分别为±11.8134%、±11.7322%,表明采用MIVM预测In-Sn合金组元的活度是可靠的。在此基础上,采用MIVM预测In-Sn合金体系的气-液平衡（VLE）数据,并与实验值进行对比,二者吻合,表明采用MIVM预测铟基合金体系的VLE是可靠的,可用于指导真空蒸馏分离铟基合金。本研究将模型预测与真空蒸馏实验相结合,不仅验证了MIVM的可靠性,还优化了真空蒸馏分离铟基合金的工艺参数,为真空蒸馏分离提纯铟基合金或处理含铟复杂物料提供指导。     

硫酸熟化—常压浸出综合回收锡烟尘中铟锌试验研究

某锡烟尘含Sn 37.43%、Zn 8.82%、In 0.56%,具有较高的综合回收价值。采用硫酸熟化—常压浸出工艺回收烟尘中的有价金属铟、锌,而锡有效富集在渣中。通过条件试验确定适宜的工艺参数为熟化温度140℃,熟化保温时间40 min,硫酸与锡烟尘质量比0.7∶1,浸出时间1.5 h,浸出温度90℃,浸出液固比4∶1 m L/g。在此条件下,铟和锌的平均浸出率分别达到96.68%和97.70%,锡的平均浸出率降低到0.52%。与常压酸浸提取工艺相比,硫酸熟化常压浸出工艺可显著提高铟和锌的浸出率,并显著降低锡的浸出率,实现了铟、锌与锡的高效分离。     

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。