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氯化铵焙烧法分解氟碳铈精矿制备晶型碳酸稀土的研究 总被引:1,自引:0,他引:1
采用脱氟剂将氟碳铈精矿中的氟转化为水溶性氟洗去,再用氯化铵焙烧法分解经预脱氟的氟碳铈精矿,直接用水浸取稀土。考察了反应温度、时间、氯化铵用量及脱氟剂用量对该矿稀土提取率的影响,脱氟精矿在焙烧温度480℃,焙烧时间1.5h,氯化剂/矿重= 2.0 时,稀土提取收率达84.3% 。其氯化选择性高,浸出液中Fe、Al、Si等非稀土杂质分别为稀土的0.10% 、0.005% 和0.016% ,经碳酸氢铵沉淀,获得了晶型碳酸稀土(折算稀土氧化物纯度92.07% )产品。 相似文献
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氧化钙对混合稀土精矿分解气相中氟的影响 总被引:1,自引:0,他引:1
研究了氧化钙对混合稀土精矿焙烧分解过程气相中氟含量的影响,采用气相色谱分析方法对焙烧过程气相中的氟进行测定,结果表明氧化钙在混合稀土精矿的分解过程中起到了固氟的作用,使焙烧过程气相中的氟含量降低60%以上。从加入氧化钙后的混合稀土精矿的焙烧产物XRD实验结果看,焙烧产物中有大量的CaF2和Ca5F(PO4)3生成,说明氧化钙对混合稀土精矿分解过程的固氟机制是CaO与其中的氟碳铈矿的分解产物REOF反应生成了CaF2,同时形成的氟化钙和氧化钙一起在800℃时能够与精矿中的独居石反应,生成Ca5F(PO4)3。 相似文献
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本文研究了稀土离子对离子选择电极测定的氟的影响,提出了用L-E混酸掩蔽消除大量称土基体的干扰直接测定稀土产品中的氟,所拟分析方法简便快速,分析结果良好。 相似文献
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采用偶氮肿Ⅲ光度法测定了稀土铝中间合金稀土总量。讨论了酸度及样品基体、干扰元素的影响。测定结果令人满意。精密度及准确度高,线性范围0.4~3.2mg/L,样品的回收率在97.1%~102.9%之间。 相似文献
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氟离子选择性电极测定载氟氧化铝中氟的含量 总被引:1,自引:0,他引:1
研究了氟离子选择性电极测定载氟氧化铝中氟,在pH=6~7总离子强度调节缓冲溶液介质中,氟离子浓度在0.95ug/mL~3.8ug/mL范围内呈良好线性关系,方法的灵敏度和选择性均较好,应用于铝电解烟气中载氟氧化铝中氟的测定。样品回收率在97%~102%之间。 相似文献
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采用优级纯HCI加二次水为介质,连续测定99.99%La_2O_3中10个非稀土杂质,采用正交设计实验L_9(3 ̄4) ̄[1],同时考虑稀土杂质的测定,对ICP-AES进行工作参数的最佳选择,并考察了基体镧的影响,指出了连续测定的最佳基体浓度和酸度,在最佳条件下,测出杂质的回收率在88.0%~107.6%之间,相对标准偏差(RSD)在3.44%~14.03%之间,检出限在0.06~3.45μg/g范围内,本方法快速、简便、准确,能满足99.99%La_2O_3产品中非稀土杂质的测定。 相似文献
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稀土氟化物中氟含量的测定:蒸馏分离,容量滴定法 总被引:1,自引:0,他引:1
稀土氟化物经高氯酸分解蒸馏的HF,HF.H2O,SiF4用硝酸镧吸收,过量的La^3+用EDTA滴定,从而算出含氟量。本方法样品加入标准回收率99.98%,应用测定含量为20%-30%稀土氟化物,其变异系数为0.37%。 相似文献
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电位滴定法测定牙膏中的氟 总被引:1,自引:0,他引:1
研究了氟的分析方法:比色法、离子色谱法、离子选择电极法。进而建立了测定牙膏中氟的新方法,利用氟离子选择电极,根据电位突跃来判断终点的电位滴定法。回收率为95%~103%,相对标准偏差RSD为0.5%~1.3%。 相似文献
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提出了用PMBP-萃淋树脂柱色谱萃取、甲酸洗脱分离稀土,在KCl介质中用偶氮胂Ⅲ显色剂光度法测定磷肥中稀土总量的方法。对三种磷肥试样测定的统计结果表明,本方法标准偏差(SD)小于1.6%、相对标准偏差(RSD)小于7%。与PMBP-苯溶剂萃取光度法测定结果相比,相对误差小于3%。本法用于磷肥中稀土总量测定,具有结果可靠、无环境污染、易于推广的优点。 相似文献
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The effect of rare earth element Ce on mechanical performance and electrical conductivity of aluminum rod for electrical purpose were studied under industrial production condition. Using optical microscope, SEM, TEM, EDS and X-ray diffractometer, the microstructure and phase composition of aluminum rod were measured and analyzed. The results indicate that the content of rare earth element Ce is between 0.05%~0.16% in the aluminum rod for electrical purpose. Its tensile strength is enhanced to some extent. The research also discovers that the tensile strength is enhanced remarkably with impurity element Si content increases. Because influence of Si is big to the conductivity, the Si content should be controlled continuously strictly in the aluminum for electrical purpose. Adding rare earth element Ce reduces the solid solubility of Si in the aluminum matrix, and the negative effect of Si on the aluminum conductor reduces effectively. So the limit of in Si content in aluminum rod for electrical purpose can be relaxed moderately. 相似文献
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Using rapes as test materials, the fastness expression and alleviation effect of rapes were studied under Cd stress condition, as the rapeseeds were dipped in the single element( La, Ce, Nd, Pr)and mixed rare earth (RE). The results indicate that, under Cd stress, the dry and fresh weight are increased by both the single element and mixed rare earth treatment, and the fastness of rape is improved. The single element of rare earth decreases the Cd content in rape roots and transmits Cd to the edible parts above the ground in which the alleviation effect of Ce is most significant. La treatment takes the second place, so that the poisonous effect of heavy metal Cd is eased. The mixed rare earth doesnt alleviate the assimilation of Cd in rape roots, but accelerates the transfer of Cd to the parts above the ground. The research puts forward that the alleviation of rare earth on Cd stress has connection with the decrease of Ca content. 相似文献
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Effects of rare earth on inclusions and corrosion resistance of 10PCuRE weathering steel 总被引:1,自引:0,他引:1
YUE 《中国稀土学报(英文版)》2010,28(6):952-956
The types,morphologies and distributions of nonmetallic inclusions in Cu-P weathering steels with and without rare earth were analyzed through a quantitative image analyzer,scanning electron microscopy(SEM)and energy dispersive spectroscopy(EDS)attached to SEM.Solid-soluble content of rare earth in the steels was analyzed by non-aqua electroanalysis and ICP.The results showed that rare earth modified the types and the morphologies of inclusions in the weathering steels.The small spherical rare earth oxysulfides and rare earth sulphides replaced the elongated MnS inclusions in the RE weathering steels.The rare earth inclusions dispersedly distributed and most inclusions were smaller than 2 μm in size.The optimum content of RE was 0.0065%-0.016% for 10PCuRE weathering steels containing about0.002% oxygen and 0.004% sulfur.Solid-soluble content of rare earth in steels was(14-20)x 10-6,which can act as a micro-alloying element.The corrosion resistance of 10PCuRE weathering steels and Q235 were studied by dry-wet cyclic immersion test.Their corrosion rates were obtained respectively.The polarization curves and pitting corrosion behaviors of weathering steels with and without rare earth were measured by electrochemical methods.The corrosion resistance of Cu-P weathering steels was improved by adding an appropriate amount of rare earth.Less and fewer rare earth inclusions largely decreased pitting susceptibility and rate of pit propagation.The pitting potential and the resistance against pitting corrosion of the RE weathering steel were significantly improved due to the modification of rare earth to inclusions. 相似文献
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针对稀土萃取过程中元素组分含量难以在线检测和实现自动控制的问题,提出通过建立多线性模型实现对元素组分含量进行软测量,并采用预测控制方法实现对稀土萃取过程组分含量的自动控制,仿真结果表明本文提出方法的有效性。 相似文献