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采用离子交换色层法用氨基膦酸螯合树脂对重稀土铥、镱、镥富集物进行动态吸附和淋洗分离研究,考察了淋洗剂浓度、酸度、淋洗液流速、温度等因素对分离的影响。结果表明,在吸附柱中,以0.1mL/(cm2.min)的流速进料时能得到较大的吸附率;在淋洗液流速为0.3mL/(cm2.min)、温度30℃的条件下,用pH=8.0、浓度0.02mol/L的EDTA淋洗重稀土富集物,可实现铥、镱、镥三者的完全分离。 相似文献
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用P_(507)萃取色谱法分离镝、钬、铒的研究 总被引:1,自引:0,他引:1
本文用萃取色谱法,以P_(507)萃淋树脂为固定相,HCl溶液为流动相。讨论了不同酸度、流速、料液组成、料液浓度、负载量、柱型及阴离子添加剂对Dy、Ho、Er分离的影响,并对不同酸度的淋洗效果作了重点分析。 相似文献
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研究了用浸渍Cyanex272的大孔磷酸树脂萃取色层分离重稀土Tm-Yb,Yb-Lu。结果表明,在淋洗液酸度2.5mol/L,稀土负载量1%,柱高径比30:1,淋洗流速1mL/min时,Yb,Lu分离效果较好;在淋洗液酸度1.8mol/L,稀土负载量0.8%~0.9%,柱高径比30:1,淋洗流速1mL/min时,Tm,Yb的分离效果较好。与使用P507萃淋树脂萃取色层分离相比,淋洗液酸度较低,而且可以减少梯度淋洗,减轻了后处理工序的生产强度,降低生产成本,对工业应用很有价值。 相似文献
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为实现我国南方离子型稀土矿的无铵浸析,以生物表面活性剂-皂角苷为浸矿剂,通过淋洗实验探讨了皂角苷浓度、溶液pH、原矿粒径、固液比对稀土淋洗效果的影响,结果表明:在原矿粒径为0.25 mm,皂角苷浓度50 g/L、pH=5.5和固液比(g/mL, 下同)1:15条件下,振荡24 h后,皂角苷对稀土的淋洗效率可达76.78 %.而在柱淋洗实验中,累积淋洗效率为43.16 %,仅不到硫酸铵的1/2;原因在于皂角苷对稀土的淋洗效率会受溶液和原矿的性质、流速等因素的影响,导致淋洗反应迟缓,拖尾期长. 相似文献
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《稀有金属》2017,(3)
目前分离镍钴最主要的方法是溶剂萃取法,但是对于高镍低钴溶液,溶剂萃取法不能取得高效而经济的分离效果。研究采用HZ818苯乙烯二乙烯基苯大孔树脂和P507,Cyanex 272萃取剂自制双萃取剂浸渍树脂,利用萃取剂的协同作用和树脂色层萃取的高分离级数分离硫酸体系中的Ni~(2+)和Co~(2+),考察了树脂的萃取容量、萃取温度、萃取pH值、淋洗温度、淋洗pH值以及淋洗速度等因素对镍钴分离效果的影响。研究表明:在Φ20 mm×200 mm的色层柱中,选用一定浓度的HAc-NaAc作为缓冲体系,控制料液pH值为4.8,以5.0 ml·min~(-1)的进料流速能取得较好的吸附效果;控制温度为28℃,淋洗流速为5.0 ml·min~(-1),用pH为4.0的HAc-NaAc缓冲溶液淋洗Ni~(2+),当淋出体积为200 ml时,改用pH 1.0的硫酸淋洗Co~(2+),并收集淋出液,得到净化的硫酸钴溶液。 相似文献
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以单一盐酸溶液为淋洗剂,采用萃淋树脂法制备超高纯氯化钕溶液。研究了CL-P507、CL-P204、001×7、001×8、D113、D900、DH100等7种树脂对RE3+、Al3+的吸附、解析、分离性能,遴选CL-P507为分离树脂、DH100为除铝树脂。单因素条件试验发现,加液方式、料液浓度、淋洗酸浓度、柱径比对流出液稀土纯度影响不显著,高料液浓度、高淋洗酸浓度、低柱径比可以获得较高浓度的超高纯氯化钕溶液,以正吸附方式加料、料液浓度30.89 g/L、淋洗酸浓度0.3 mol/L、柱径比20︰1为最优工艺条件,制备了纯度>99.999%的超高纯氯化钕溶液。工艺不使用任何延缓离子,从源头控制非稀土杂质的引入,为超高纯稀土溶液的制备提供了技术参考。 相似文献
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采用离子色谱法分离电导检测废气中甲酸的含量。考察Dionex IonPac AS18和Ion-PacAS11-HC色谱分离柱在不同淋洗液浓度条件下对甲酸的分离效果,淋洗液流速对分离的影响。讨论绘制校准曲线时标准溶液介质的选择。结果表明:当用Dionex IonPac AS18柱,5mmol/L氢氧化钾为淋洗液,以1.0 mL/min的淋洗速度进行梯度洗脱并用吸收液配制校准曲线的标准溶液时可达到预期废气中甲酸分析的目的。该法线性范围为0.1~10 mg/L和10~100 mg/L,检出限为0.007 mg/m3。用本法测定甲酸生产装置30 m高度排气筒废气中的甲酸回收率为88%~104%。 相似文献
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采用振荡淋洗方法对三种粒径(+2mm、-2mm+0.15mm、-0.15mm)某尾矿库周边铀污染土壤进行去污试验,选用盐酸、硝酸、柠檬酸、草酸为淋洗剂,通过控制淋洗浓度、液固比、时间、温度、混合淋洗等因素来确定较优的淋洗条件。结果表明:各淋洗剂对铀污染土壤的去污效果为草酸盐酸硝酸柠檬酸;当淋洗浓度大于0.5mol/L、淋洗时间大于8h或液固比大于10∶1时,其淋洗效果都逐渐趋于稳定;提高淋洗温度可显著提升淋洗效果;选用草酸+盐酸和草酸+硝酸两组较优混合淋洗组合对全粒径土壤进行淋洗时,土壤中铀去除率均达50%以上,总含铀量分别降至27.15、24.32mg/kg,均达到土壤修复目标(40mg/kg)。 相似文献
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Methodsfor the synthesis of acidic phenyl-and substituted phenylphosphonates bearing a branched longchain ester alkyl group are described.These synthetic routes are incomparably superior to other methods in vari-ous aspects including better reaction yield and higher purity of the product.The behaviour of themono(2-butyloctyl)esters and mono(2-methyldodecyl)esters of both phenyl-and o-methylphenylphosphonicacids thus obtained in extraction of lanthanum,praseodymium,neodymium and lutecium as representatives oflight and heavy rare earths,is investigated and discussed on the basis of their chemical structure.The dependenceof the extraction constants and separation factors accords with the Reactivity-Selectivity Principle in solvent ex-traction proposed by us.The composition and structure of the extracted species have been characterized byinfra-red and proton nuclear magnetic resonance spectroscopy in addition to elemental analyses. 相似文献
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Chiral separations of basic enantiomers were carried out by using a cationic cyclodextrin (CD), quaternary ammonium beta-cyclodextrin (QA-beta-CD), under counter-electroosmotic flow (counter-EOF) conditions. The special characteristics of using a cationic CD to separate cationic enantiomers is that the EOF can be reversed and the analyte-CD complexation is reduced. This is especially useful for chiral separation of cationic compounds, which strongly bind with neutral and anionic CDs (such as tricyclic amine compounds). The reduction in the binding constants between the CD and the cationic enantiomers makes it easier to control the optimum CD concentration. The application of the cationic CD also eliminated the peak tailing problem caused by electrodispersion. The effect of pH and the concentration of QA-betaCD on chiral separation has been studied. At pH 3.02, no separation for any of the enantiomeric amines was observed. At pH 8.20, chiral separation of some tricyclic compounds was achieved at very high resolution due to the counter-EOF setup. At pH 11.6, most enantiomers were neutral and chiral separation of some bicyclic compounds can be obtained. 相似文献
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《Hydrometallurgy》2006,83(3-4):137-143
The separation of In(III), Ga(III) and Zn(II) from sulfate solution has been studied using an extraction resin containing 2-ethylhexyl phosphoric acid mono(2-ethylhexyl) ester (P507 extraction resin). The effect of pH on the extraction of each metal was determined. Extraction isotherms were then constructed at selected pH. Results show that In(III) is first extracted from aqueous solutions at pH 2.0 using this resin while Ga(III) and Zn(II) are co-extracted at pH 3.0. Their separation can be carried out using HCl of different concentrations as eluants. The saturation adsorption capabilities of indium(III) and gallium(III) were evaluated as 47.2 and 31.0 mg/g or 0.41 and 0.44 mmol/g, respectively. The molar ratio of metal ion: P507 reagent on resin was about 1:3. Loaded resins can be regenerated, and the metals can be recovered selectively. Two fixed-bed columns arranged in-series were successfully used for the separation and recovery of these three metal ions from a multi-component solution. 相似文献
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H. B. Kushkhov R. A. Kardanova V. V. Khasanov I. A. Borukaeva 《Russian Metallurgy (Metally)》2018,2018(8):742-746
The results of high-temperature electrochemical synthesis of holmium–iron triad metal intermetallics in chloride melts are presented. The influence of the current density, the composition of an electrolysis bath, and the synthesis time on the electrolysis processes and the composition of the end product is studied. The electrolysis of the molten KCl–NaCl mixture containing 0.5–2.5 mol % holmium trichloride and 0.1–2.5 mol % nickel (cobalt) dichloride at a current density of 0.5–2.0 A/cm2, a temperature of 973–1073 K, and an electrolysis time of 30–90 min is shown to cause the formation of a cathode deposit in the form of a “metal–salt pear” on a tungsten electrode. This pear consists of a mixture of metallic nickel (cobalt) and HoNi, HoNi5, and HoNi3 (HoCo2, HoCo3, HoCo5, Ho2Co17) intermetallics. The intermetallic compound content in the cathode deposit is found to increase at a constant current density (1.2 A/cm2) and when the holmium chloride content in a melt or the ratio of the holmium chloride concentration to the nickel (cobalt) chloride concentration increases. Only a mixture of holmium–nickel (cobalt) intermetallics can exist in the cathode deposit if the electrolysis bath composition and the electrolysis parameters are controlled. The electrochemical synthesis of holmium–iron intermetallics was performed under galvanostatic conditions in molten KCl–NaCl–HoCl3. Iron ions are introduced in a melt via the anodic dissolution of metallic iron. The results of X-ray diffraction analysis of the electrolysis products demonstrate the fundamental possibility of synthesizing holmium–iron intermetallics. The optimum conditions of electrosynthesis of holmium–iron triad metal intermetallics are determined. 相似文献
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BA Brown DE Griffith W Girard J Levin RJ Wallace 《Canadian Metallurgical Quarterly》1997,24(5):958-964
The polymerized surfactant poly(sodium N-undecylenyl amino L-valinate) [poly(L-SUV)] has been used in micellar electrokinetic capillary chromatography for the chiral separation of various acidic and basic drugs, as well as neutral compounds. Under the conditions studied, poly(L-SUV) was shown to be a very versatile anionic chiral selector in the pH range of 5.6-11. The micelle was used for the enantioseparation of coumarinic anticoagulant drugs with various buffers under moderately acidic conditions. Neutral and alkaline buffer conditions were used to successfully separate the neutral atropisomers (+/-)-1,1'-bi-2-naphthol, (+/-)-1,1'-binaphthyl-2,2'-diamine, and Tr?ger's base. Chiral separation of the cationic paveroline drugs, laudanosine, norlaudanosoline, and laudanosoline, was influenced by pH and the use of coated capillaries. The acquired data focused on optimizing the migration times, capacity and separation factors, and electrophoretic mobilities of the various racemic mixtures. 相似文献
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A. N. Bushuev O. V. El’kin I. V. Tolstobrov A. V. Sazanov D. A. Kondrat’ev 《Russian Metallurgy (Metally)》2018,2018(8):771-776
Cyclic voltammetry is used to study the electrolytic reduction of holmium ions on a nickel electrode in a holmium chloride-containing equimolar molten mixture of sodium and potassium chlorides in a temperature range of 1073–1173 K. The potentials of formation of nickel–holmium intermetallic compounds (IMCs) are determined. Nickel–holmium intermetallic compounds are synthesized by controlled potential electrolysis. Under the selected electrolysis conditions, the prepared coating is shown to be single-phase and its composition corresponds to the HoNi2 stoichiometry. The coefficients of reaction diffusion of holmium in nickel are calculated and the activation energy of alloy-formation process is determined. 相似文献