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1.
The extraction of nickel, cobalt, copper and zinc from ammoniacal solutions of ammonium carbonate or ammonium sulphate by solutions of Hostarex DK-16 in kerosene has been investigated as a function of phase contact time, aqueous-phase pH and organicphase reagent concentration. Besides copper, Hostarex DK-16 also partially extracts iron (III) from moderately acidic solutions whereas nickel, cobalt(II), copper and zinc are extracted from neutral or ammoniacal ammonium sulphate and ammonium carbonate solutions. Extraction decreases in the following order of metals: Cu > Co > Ni > Zn. Cobalt(III) is not extracted, but the complex of cobalt(II) with Hostarex DK-16 is slowly oxidized to a cobalt(III) complex which cannot be stripped even when 10 N sulphuric acid is used. Absorption spectra for cobalt complexes with Hostarex DK-16 (purified by preparative thin-layer chromatography) in benzene also suggest oxidation of cobalt(II) to cobalt(III) in the organic phase. Nickel, cobalt(II), zinc and copper can be stripped easily from organic solution with dilute solutions of sulphuric acid. Hostarex DK-16 extracts iron very slowly, nickel moderately rapidly and copper, cobalt(II) and zinc rapidly. Slope analysis and extraction isotherms suggest that the complexes CuR2, NiR2 ·HR and CoR2·HR are present in the organic phase. Nickel can easily be separated from cobalt by extraction with Hosterex DK-16 after oxidation of cobalt in aqueous ammoniacal solution by hydrogen peroxide; however, LIX 64N seems to be a more promising extractant owing to the higher extraction of nickel under analogous conditions and the poorer extraction of zinc in comparison with Hostarex DK-16.  相似文献   

2.
分别采用液相还原改性法和微乳液法制备超细铁颗粒,用乙醇-水体系制备镍包覆铁颗粒的Fe/Ni双金属颗粒,用来进行硝酸盐的降解实验,并用扫描电镜(SEM)和X射线衍射(XRD)分析超细粉末的物相结构及形貌.结果表明:通过液相还原改性法制备的超细铁粉,颗粒形状不规则,颗粒大小在0.2~0.3 μm之间;而用乙醇-水体系制备的铁/镍粉颗粒为等轴晶粒,颗粒大小也在0.2~0.3 μm之间;加入PEG-6000可改善液相改性法和醇-水法制备的铁粉的分散性.微乳液法制备的铁粉为球形颗粒,存在较明显的团聚现象,颗粒大小在0.5~ 1μm之间.在相同条件下,不同方法制备的超细铁粉降解硝酸盐的能力由高到低依次为:微乳液法制备的铁粉>乙醇-水体系法制备的Fe/Ni双金属粉>液相还原改性制备的铁粉>不加PEG的乙醇-水体系制备的铁粉.  相似文献   

3.
The effect of powdered nickel additions (10–33 mass %) on the oxidation kinetics of double titanium-chromium carbide produced by the method of self-propagating high-temperature synthesis, and also that of plating the synthesized carbide powder with nickel (26 mass %) was studied. The effect of nickel concentration and powder particle size on the oxidation resistance at different temperatures was different. However, it can be stated that plating the carbide powder with nickel increased its oxidation resistance at all temperatures in the range 600–1000°C, excepting 700°C. The degree of oxidation of the carbide and nickel constituents were estimated. Activation energies for the initial and parabolic stages of oxidation were determined. Translated from Poroshkovaya Metallurgiya. Nos. 1/2(411), pp. 76–82, January–February, 2000.  相似文献   

4.
High-temperature oxidation of diamond powder and that coated with Ni-P has been studied by differential thermal analysis. It is shown that the temperature for active oxidation of uncoated powder is 820°C and that for composite powder is higher by 100°C. According to the thermogravimetric and DTA curves two kinds of chemical reaction are found for weight loss, i.e. with CO formation at the specimen surface (low-temperature TG curve parabolic region) and CO2 formation (high-temperature linear region). A catalytic effect of nickel on CO formation is established.Institute of Materials Science Problems, Ukrainian National Academy of Sciences, Kiev. Translated from Poroshkovaya Metallurgiya, Nos. 1/2(383), pp. 55–58, January–February, 1996. Original article submitted April 15, 1994.  相似文献   

5.
It is shown to be possible to make finely divided Fe-Co-Ni powders with given physicochemical properties. Iron, cobalt, and nickel oxalates have been made by chemical methods. Hydrogenous media have been used in the thermal decomposition of the iron oxalates to give finely divided powder that are nonpyrophoric and corrosion resistant and which have high contents of the metallic phase and given magnetic properties. These powders have been used in sealing composites for pipelines, and also as fillers in lacquers and magnetic liquids for general purposes.Institute for Colloid Chemistry and Water Chemistry, Ukrainian National Academy of Sciences, Kiev. Translated from Poroshkovaya Metallurgiya, Nos. 3/4(384), pp. 111–113, March–April, 1996. Original article submitted June 20, 1994.  相似文献   

6.
黄冰 《铜业工程》2020,(2):58-62
研究了以臭氧和氟化钠为脱杂试剂,采用"溶解造液--强氧化除铁钴--氟化除钙镁--结晶析出"为主干的工艺处理粗硫酸镍,深度脱除其中的铁、钴、钙、镁杂质的工艺可行性及最佳工艺条件。试验结果表明,以臭氧为强氧化剂,可深度脱除粗硫酸镍中的铁钴杂质,最佳反应条件为:反应温度80℃,时间8h,终点pH值4.5~5.0,反应终点溶液中铁、钴浓度小于0.005g/L;以氟化钠做添加剂,可深度脱除粗硫酸镍中的钙镁杂质,最佳反应条件为:反应温度90℃,时间2h,pH值5.5,氟化钠添加系数1.5,反应终点溶液中钙0.007g/L,镁0.005g/L;将"强氧化除铁钴"与"氟化钠除钙镁"工序相结合,可获得更好的除杂效果。  相似文献   

7.
Discrete event simulation (DES) is a suitable framework to evaluate and optimise the dynamics of sulphide smelters. In particular, iron–nickel–copper–cobalt sulphides undergo continual oxidation within a roasting or smelting operation, followed by batch oxidation within the converting operation, thus producing iron-free Bessemer matte (or blister copper, in the case of copper smelters); this semi-finished product undergoes further processing to produce nickel, copper and cobalt products, and to recover precious metals. The juncture between continuous smelting and batch converting is often an appropriate focus for the earliest phases of DES development, since it is typically a major bottleneck within nickel and copper smelters; later phases may include increasing levels of detail for auxiliary unit operations, as well as plant logistics. Moreover, DES can support matte-slag chemistry, including Gibbs free energy balances to determine the iron speciation within the slag. DES is therefore capable of linking the fundamentals of oxidation reactions to the intricacies of plant dynamics.  相似文献   

8.
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   

9.
本文介绍了攀枝花硫钴精矿浸出净化液镍钴分离及钴产品制备的试验研究。钴镍分离采用P507萃取,钴的萃取率大于99.5%,镍的萃取率在0.01%以下。有机相用硫酸反萃得到硫酸钴溶液,用盐酸反萃得到氯化钴溶液。由氯化钴溶液可制取纯氧化钴粉;由硫酸钴溶液可制备结晶硫酸钴;由萃余液可沉淀出碳酸镍粗产品。  相似文献   

10.
废高温镍钴合金浸出液净化试验研究   总被引:4,自引:4,他引:0  
在"苏打焙烧-碱浸出-氯气浸出-TBP萃取除铁-中和水解除铬-P204萃取除微量杂质-N235萃取分离镍、钴"处理废高温镍钴合金工艺的基础上,重点研究了废高温镍钴合金浸出液的净化工艺,确定了废高温镍钴合金浸出液净化的较优工艺技术参数。采用该净化工艺条件可将浸出液中的杂质元素有效地脱除,处理后所得镍、钴溶液成份满足某公司镍、钴产品生产的要求。  相似文献   

11.
ElectrodeCharacteristicsofMmNi_5-typeAlloysforNickel-metalHydrideBatteriesGengMing-Ming(耿鸣明)(DepartmentofPrecisionAlloy,Centr?..  相似文献   

12.
《粉末冶金学》2013,56(4):57-78
Abstract

A process is described for producing elongated single-domain (ESD) fine-particle magnets. The 150-Å. ESD iron or iron–cobalt alloy particles are prepared by controlled electrodeposition into mercury, followed by thermal growth and treatment with a third metal to attain optimum particle shape and magnetic properties. The particles are then aligned by a magnetic field, compacted under pressure, freed of mercury by vacuum distillation, and embedded in a suitable matrix. This is ground to a coarse powder and fed into automatic presses for realigning and compacting to the final magnet shape. The factors controlling each step of the process are discussed, and the advantages of magnets with artificial microstructures synthesized by this approach are pointed out. The process described produces commercial ESD iron and iron–cobalt magnets with energy products of 2·2 and 3·5 million gauss-oersteds, and laboratory ESD iron and iron–cobalt magnets of 4·2 and 5·0 million gauss-oersteds.  相似文献   

13.
The reducibility of several types of lateritic nickel bearing ores was investigated. The ores were reduced with hydrogen over a temperature range of 673 to 1273 K and reaction times from 5 to 80 minutes. The fraction of nickel, iron, and cobalt reduced to the metallic state was determined by leaching the reacted samples with a bromine-methanol solution followed by atomic absorption analysis for the individual elements. The reducibility of nickel increased with increasing iron concentration of the ore. Increased reduction temperature greatly raised the amount of nickel reduced for ores with high iron concentrations. The cobalt reducibility decreased with increasing iron concentration of the ore. Changes in reduction temperature affected cobalt reduction less than nickel reduction. The observed changes in reducibility have been attributed to the formation of phases which incorporate nickel and cobalt. The major ore components were plotted on the ternary phase diagram of the SiO2+(Al2O3)-MgO-FeO system. It is shown how this plot can be used to predict the reducibility of different types of lateritic ores. Formerly with the Department of Metallurgy and Materials Science, University of Toronto, Toronto, ON, Canada  相似文献   

14.
The solubility of nickel and cobalt in silica saturated iron silicate slags in equilibrium with nickel-gold and cobalt-gold alloys has been investigated under controlled oxygen pressures in the temperature range of 1250 to 1350°C. It was found that the metal solubility increased with 1) decreasing temperature, 2) increasing oxygen pressure, and 3) increasing metal content of the alloy. The solubility of cobalt in the slag was found to be much higher than that of nickel. The solubility of the metal in the slag from its alloy can be explained by a simple oxidation process.  相似文献   

15.
综述了国内外镍、钴粉末,特别是超细和纳米镍、钴粉末制备技术的研究和镍、钴资源的再生利用状况;概述了国内外镍、钴粉末的应用及生产状况;分析了我国镍、钴粉末生产企业现状;展望了未来10年镍、钴粉末生产工业的发展趋势,提出了我国镍、钴粉末生产工业发展的对策。  相似文献   

16.
In our earlier studies [1–4], conditions were optimized for leaching converter slag with ferric chloride/dilute sulphuric acid for the recovery of cobalt, nickel and copper. By using both leachants most of the copper, nickel and cobalt values could be solubilized. Subsequent treatment of the leach liquors for separation and recovery of metals was difficult due to the presence of large quantities of iron in relation to other metal concentrations. In the present work, an attempt has been made to develop a process based on pressure leaching of the slag with dilute sulphuric acid in which iron contamination could be minimized by oxidation and hydrolysis. Various parameters including leaching time, pulp density, particle size, concentration of acid and oxygen partial pressure were studied to optimize the solubility of metal values. Under optimum conditions about 90% copper and more than 95% each of nickel and cobalt could be extracted with only 0.8% extraction of iron.  相似文献   

17.
The reducibility of several types of lateritic nickel bearing ores was investigated. The ores were reduced with hydrogen over a temperature range of 673 to 1273 K and reaction times from 5 to 80 minutes. The fraction of nickel, iron, and cobalt reduced to the metallic state was determined by leaching the reacted samples with a bromine-methanol solution followed by atomic absorption analysis for the individual elements. The reducibility of nickel increased with increasing iron concentration of the ore. Increased reduction temperature greatly raised the amount of nickel reduced for ores with high iron concentrations. The cobalt reducibility decreased with increasing iron concentration of the ore. Changes in reduction temperature affected cobalt reduction less than nickel reduction. The observed changes in reducibility have been attributed to the formation of phases which incorporate nickel and cobalt. The major ore components were plotted on the ternary phase diagram of the SiO2+(Al2O3)-MgO-FeO system. It is shown how this plot can be used to predict the reducibility of different types of lateritic ores.  相似文献   

18.
镍钴粉末生产现状及发展趋势   总被引:10,自引:0,他引:10  
本文综述了国内外镍、钴粉末,特别是超细和纳米镍、钴粉末制备技术的研究和镍、钴资源的再生利用状况;概述了国内外镍、钴粉末的应用及生产状况;分析了我国镍、钴粉末生产企业面临的现状;展望了未来十年镍、钴粉末生产工业的发展趋势,提出了我国镍、钴粉末生产工业发展的对策。  相似文献   

19.
The reactions of three types of binders based on cobalt, iron (V-21), and copper and nickel (B-13) in the production of diamond tools by hot pressing are considered. Pressure intensifies the reactions of the basic components of cobalt and B-13 binders with diamond. Active solution of diamond in cobalt is observed. In B-13 binder, the diamond reacts with the solid solution based on α-Fe to form iron carbides Fe3C. At diamond-binder contact, active chemical reaction leads to embrittlement of the binder and the appearance of cracks in chip manufacture. Adding AM 14/10 diamond powder to V-21 binder and sintering at 860°C for 9 min does not change the parameters of the iron-based solid solution. In other words, the binder-diamond reaction is considerably slower, and no embrittlement of the diamond-binder contact zone is observed.  相似文献   

20.
The utilization of ozone for the separation of cobalt from nickel sulfate was investigated by determining the oxidation rate for Co(II) and Ni(II) ions under various ozonation conditions at 60°C. The oxidation reaction was observed to follow a first order rate with respect to the ozone partial pressure of the O3-O2 mixture gas and to be promoted considerably by vigorous agitation. The oxidation rates were virtually constant down to a fairly low concentration of the oxidizable ions. Nickel ion was found to be oxidized more easily at lower pH in the mixed sulfate solutions than in solutions of a single sulfate. At pH 2.5–5.0, ozone oxidation seems to be effective to separate cobalt ions selectively from nickel sulfate solutions, due to the extremely slow oxidation of the nickel ion in comparison with cobalt.  相似文献   

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