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By Takahiko Okura, Satoshi Okano, Hiromichi Takebe

"Fine zinc concentrates tend to become sticky when roasted in a fluidized-bed reactor. The oxidation of high-purity ZnS powders and ZnS concentrates with different particle sizes were studied in terms of phase changes and particle morphologies. The sample materials were directly oxidized to ZnO in a roasting process performed over 700°C. Zinc oxide particles with diameters less than 0.5 ìðé formed at 700°C; the particle size increased by grain growth at 900°C. The coarse ZnS concentrate formed the oxysulfate ZnO2ZnS04 when roasted at 700°C; the sulfate transformed to ZnO at higher temperature.1. IntroductionRoasting is an important step in zinc extractive metallurgy because more than 80% of the world's zinc is produced from zinc sulfide concentrates using the roast-leach-electrowinning [1,2]. Currently, zinc concentrates with a finer particle size distribution are used to enhance recovery rate. However, the finer zinc concentrates tend to produce a sticky calcine in a fluidized-bed roaster [3].The factors that affect products in a fluidized-bed roaster include particle size, contaminant, O2 and SO2 partial pressures, and the feeding method of ore to the roaster. This study examined roasting behavior of high-purity ZnS powders and ZnS concentrates with different particle sizes. The phase changes and particle morphologies of the calcine samples producted from theZnS powders were studied."

Jan 1, 2012

By Edilson Marques Magalhães, Danielly Da Silva Quaresma, José Antônio da Silva Souza, João Nazareno Nonato Quaresma, Emanuel Negrão Macêdo

"The production of alumina from bauxite using the Bayer process generates the residue known by red mud. This material can be used as a source for concentration and recovery of valuable metals such as titanium. The greatest difficulty of concentrating titanium compounds is the large amount of iron oxide present in red mud > 30% by weight. This paper shows the extraction of the iron oxide, increasing the concentration of the titanium compounds. The red mud is leached with H2SO4 at 30% concentration and temperature range of 60°C, 80°C and 90°C. Analysis of the leached and concentrated was made to verify the effectiveness of the iron oxide extracting process and the titanium compounds concentration viability.2- IntroductionIn the state of Para is located the Industrial Unit Alumina of North of the Brazil S/A (Alunorte), created to produce and commercialize alumina, aluminum oxide, Al2O3. The ALUNORTE with Aluminum Brasileiro S/A (Albras) and Mining Rio do Norte S/A (MRN) complete the production cycle of aluminum in the state. Although the production of alumina has a importance great for the socio-economic status, as in any area other, generates a amount large of waste, thus causing environmental impacts. Pará State has produced 25 million tons of bauxite (Pinto, 2010), of which 60% were transformed into alumina plant in Pará and Maranhão by ALUNORTE by ALCOA, generating approximately 9,000,000 tons of waste known as Red Mud (RM). Due to the high reactivity this material is considered dangerous, and currently there is no operating process capable of reuse all the material produced at any refinery. The search for industrial processes in order to reuse these wastes can contribute to reducing the overall impact of the production process of alumina. In this context, this paper estudied, within the research line of Solid Waste valorization the mining industry and metallurgy, a process that makes possible the red mud as a source of raw material, in other words, seeks to maximize the use of red mud as raw material for concentration and or recovery of titanium compounds in both the crystalline form of anatase, rutile and ilmenite, avoiding the predatory extraction of natural resources of these materials. Applying definitely the concept of self-sustainability of the mining industry and metallurgy."

Jan 1, 2012

By LeoJ. Miller

Exploration for an ore deposit commences with an outline of the regional ore controlling environment and is followed by the application of tools to focus the target area. One of the most essential focusing is the mapping of the mineral assemblages within the area of the ore. Key elements of mineralizing fluids, either epigenetic or syngenetic, enter into mineral assemblages that extend far beyond ore deposits. Portions of these assemblages may consist of new matrix minerals or alteration of previously existing minerals. Today, ore deposits are divided into genetic classes and each class is d8fined by a specific geological environment. Ore deposits within a given class are associated with a mineralogy, that is characteristic of the ore deposit class. So faithful is the mineral assemblage surrounding, or within an ore deposit, that recognition of the assemblage may be sufficient to define the class. Porphyry copper deposits have long been noted for their halos of alter-ation minerals. The outermost ring of chlorite, epidote and calcite extend thousands of feet away from the main ore zone. The mineral associated with porphyry copper deposits have been well documented by our distinguished speaker Paul Kerr, at Santa Rita (1), and Silver Bell' (2), and by excellent papers from S. C. Creasey, 1959 (3), Sales, 1948 (4), T. S. Lovering, 1949 (5), our Co-Chairman John Guilbert, 1970 (6), and many others. Several recent porphyry copper mines have been discovered in recent years by utilizing the mineral assemblage model described by Lowell and Guilbert, 1970 (6). Dave Lowell applied his own model of mineral halos for the discovery of Kalamazoo at San Manuel (7), Arizona, and Casa Grande West, Arizona. The purpose of this paper is to outline the application of mineralogy for discoveries of deposits other than porphyry copper mines and in particular, to ore discoveries in which mineralogy has played a key roll.

Jan 1, 1981

By Huimin Lu, Lian Zhou, Qiang Li

"A three-dimensional mathematical model is developed for the regenerative rotary hearth furnace with 40 meters medium diameter. The influence of combustion switchover and outlet pressure on the fluctuation and distribution of temperature and pressure is studied with numerical simulation method. The results showed that the temperature field and flow field is suitable for requirement of industrial production; the fluctuation of the temperature field and pressure is acceptable; the influence of outlet pressure on the furnace pressure is great.IntroduceRotary hearth furnace which is originally utilized as heat treating and reheating industrial furnace, now is also used for carbon based DRl production. With the need of market and the concern of resource recycling and environmental issues, the DRl production from ore or from waste material by rotary hearth furnace attracts more and more attentions from steel industry [1,2].When rotary hearth furnace works, the feed pellets are charged on the hearth and rotate within an annular furnace chamber with the process of reduction. For the sake of rapid reduction, usually the depth of the pellet is one or two layers, accounting for less than 90% of the volume of furnace. As result, the exhaust gases carry away a lot of heat, so that energy utilization efficient is low [3]. Currently, in order to reduce the consumption of energy and improve the production efficiency, many methods have been adopted. The regenerative combustion technology is one of the most promising."

Jan 1, 2013

By Heng Yi

The salt lake brines that lithium is extracted from have high chloride levels making the brine very corrosive to stainless steel extraction column internals. This is a significant problem in column scale-up to industrial production. Two types of corrosion-resistant ceramic internals, the hybrid ceramic internal and ceramic plate, were designed and tested under pilot conditions for future industrial application in this field. The hydrodynamic results (Yi et al. Ind Eng Chem Res 56 (4):999–1007 (2016), [1]) show that holdup of hybrid ceramic internal is higher than that of ceramic plate by around 50%, while Sauter mean diameter when using the hybrid ceramic internal is smaller than when using the ceramic plate by around 30%. This results in a larger mass transfer area, hence better mass transfer efficiency for the hybrid ceramic internal. Axial dispersion and mass transfer parameters are also examined (Yi et al. Ind Eng Chem Res 56(11):2049–3058 (2017), [2]). The results show that the column with hybrid ceramic internals has 50% lower axial dispersion coefficient and 50% higher mass transfer coefficient, leading to higher mass transfer efficiency. The transfer unit height of the column using hybrid ceramic internals can be as low as 0.2 m, showing very good efficiency. This is promising for near-future applications. Two-phase computational fluid dynamics (CFD) models have been developed for the two columns with ANSYS FLUENT commercial software. CFD successfully predicts the higher holdup and lower axial dispersion coefficients for the hybrid sieve plate pulsed column as measured in the experiments, and the cause for the difference in performance has been explained with information from CFD.

By Robert G. Robins

Precipitation of ferric arsenate is an effective method for removing arsenic(v) from hydrometallurgical process solutions. The solubility and stability of this compound. FeAs04.2H20, has received some attention in recent years and the reported solubilities of amorphous and crystalline material have varied considerably. This paper reviews previous studies and reports some recent work with a consistent model to explain the variable results. Free energy data for ferric arsenate and its associated dissolved complexes are presented.

Jan 1, 1990

By Shadia J. Ikhmayies

"Nanocrystalline fluorine doped tin oxide (Sn02:F) thin films were produced by the spray pyrolysis technique (SP) on glass substrates at a substrate temperature T, = 450 ° C. The hydrated stannous chloride (SnClz.2H20) was used as a precursor and ammonium fluoride (NH4F) and hydrofluoric acid (HF) were used as the doping compounds. A comparison between the compositional, morphological and optical properties of the films obtained by using the two doping compounds was performed by using scanning electron microscope (SEM) observations, energy dispersive spectroscopy by X-rays (EDAX) and transmittance measurements. It is found that the films prepared by using HF have larger grain size, and higher fluorine content than the films prepared by using ~- In addition these films have higher transmittance and higher direct optical bandgap energy. These results are interesting for the use of Sn02:F as a forecontact in CdS/CdTe solar cells.IntroductionTin dioxide is an n-type, wide bandgap semiconductor (about 3.5 eV) and in the form of thin films, it is a transparent conducting material, characterized by high optical transmission (80- 90%) [l]. Sn02:F is the most widely used transparent-conducting oxide material. The transparent-conducting thin films of this oxide are used as electrodes in a variety of optoelectronic devices, as heat mirror coatings in 'smart windows' for buildings, in automobile and airplane windshields, in incandescent light bulbs, in flat-plate and concentrating solar collectors. Tin oxide and zinc oxide, in thin film configuration are technologically important materials because of their applications in photovoltaic cells [2].Among various dopants for Sn02, fluorine is often preferred, because fluorine doping results in films with high transparency and good conductivity [3]. By exploring the literatures, it was found that different sources of fluorine were used to produce Sn02:F thin fihns, among which are ammonium fluoride (NH4F) and hydrofluoric acid (HF) are the most used. Some researchers used~ [2, 4-7] and others used HF [3, 6-8] for doping Sn02 films. Gordillo et al.[7] used both of NH4F and HF and showed that the resistivity of thin films obtained by using HF was lower than that of similar films obtained by using NH4F by a factor of 2.2. They also found that the films obtained by using HF have more random orientations."

Jan 1, 2013

By Florian Kongoli

The optimal operation of the blast furnace depends considerably on the properties of the sinter fed into the furnace. As a result, the optimization of the sintering processes has a direct effect on the overall effectiveness of the iron making processes. In order to produce a good sinter special care needs to be taken in order to assure it has a good permeability and reducibility and it is able to retain these properties for a certain time. If the sinter starts to melt down early in the upper part of the blast furnace, where its solid state reduction is essential, permeability decreases, the gas channels get blocked, reductibility diminishes and serious problems may also follow. Among the factors that influences the above mentioned sinter properties are the oxygen potential and fluxing components. Nevertheless, their effect on the phase relations during sintering and sinter reduction conditions has not yet entirely clarified and confusion exists in literature. This quantification becomes even more important today where many new minor components such as Al2O3 and MgO enter the sinter through raw materials. This work quantifies the effect of oxygen potential and fluxing components such as alumina and magnesia on the liquidus and phase relations of the sinter primary melts in the iron rich portion of CaO-FeO-Fe2O3-SiO2 system at sintering conditions. This is carried out by the means of new type of industrial diagrams in the form of Fe/CaO vs. SiO2 that can directly help the optimization of the sintering processes.

Jan 1, 2006

By W. J. Guay

Scrubbing of simulated copper reverberatory furnace gases containing 1.0 percent sulfur dioxide with the minus 74 ~m fraction of the San Manuel tailings has shown sulfur dioxide removals of almost 100 percent over an effluent pH range of 3.1 to 4.6 and a wide range of liquid to gas ratios with absorptions of 11 to 17 Kg of sulfur dioxide per tonne of minus 74 um slimes. The high reactivity of the tailings slimes with S02 indicates that the reaction rate is not controlled by the slow dissolution of calcium carbonate in sulfurous acid which characterizes scrubbers using ground limestone. The interpretation of these results has been considerably enhanced by wet chemical analysis and emission spectrographic analysis which show that calcium and iron account for about 90 percent of the SO2 absorption with the rest being accounted for by aluminum, magnesium, potassium, and sodium. Mineralogic examination confirms the, chemical and spectrographic analyses showing that the major constituent removed from the slimes is calcium carbonate, with lesser amounts of chlorite and montmorillonite (silicates containing iron, magnesium, aluminum, and calcium) being removed.

Jan 1, 1981

By M. Demuth, B. Holleis, M. Potesser, D. Spoljaric

"In 2005, Messer Group established a technology competence centre for metallurgy in Gumpoldskirchen (Austria), with the aim to develop oxygen burners which satisfy today's and upcoming standards of legislation as well as customer requirements. With the assistance of the Development Sponsorship Fund (FFF) of Austria, cooperation with the University of Leoben was agreed on. With the long term experience of the Gas-Warme-Institut ""GWI"" in Essen (Germany) and the University of Leoben, different new burners have been developed.The efficiency of industrial combustion processes can be increased in two ways (which can be seen in Figure 1 ), either by preheating the fuel and combustion air or by adding oxygen. Due to the high 79 % Nz ballast in air combustion, only low flame temperatures can be reached. This results in high heat loss in the exhaust gas, caused by the low combustion efficiency. Oxygen can be introduced into the combustion chamber using different techniques:• Oxygen fuel burners• Direct oxygen injection into the fuel air flame• Underlaying of the fuel air flame• Enrichment of the combustion airIn Figure 2, the theoretical flame temperature for the stoichiometrical combustion of natural gas is plotted as a function of oxygen enrichment. Therefore, it can be concluded that even low enrichment values produce higher flame temperatures and result in higher combustion efficiency."

Jan 1, 2012

By Adam Powell, David Dussault

"Electric Field-Enhanced Smelting and Refining is a process for driving the reaction between carbon in hot metal and iron oxide in slag, for example, in a steelmaking reactor. This process involves inserting electrodes into the slag and metal phases, such that the overall reaction FeO + C -> Fe + CO is separated into two half-cell reactions: Fe2+ + 2e· -> Fe at the cathode in the slag, and C + O 2 • -> CO + 2e· at the anodic slag-metal interface. Without the electrodes, the reaction is very slow, but with electrodes, the additional surface area available to the ferrous ions for reduction accelerates the reaction even without any applied bias. When a bias is applied to the electrodes, the electric field across the slag further accelerates the overall reaction.With or without applied bias, the process is first-order in the ferrous ion concentration, and limited by ferrous ion transport to the cathode. To complicate matters, as the liquid iron is reduced at the cathode, the Mullins-Sekerka instability leads to formation of dendrite-like liquid iron fingers which grow into the slag. Because of this, the design of the cathode can have a significant effect on the overall process kinetics, and understanding of the dynamics of these fingers and of their effect on mass transfer is necessary for the intelligent design of the overall process and the cathode in particular.Toward this end, a detailed mesoscopic two-phase slag-metal model is presented here which describes multi component diffusion in the slag and fluid flow in both phases in the vicinity of the cathode. Diffusion in the slag is driven by chemical and electrical potentials. The phase boundary is modeled as a diffuse interface using a phase field approach. Because this electrochemical reaction occurs at high-temperature, the kinetics of charge transfer and adsorption through the double layer are fast relative to transport, permitting the use of simple linear reaction kinetics. This also eliminates the need to discretize the double layer, with the result that charge neutrality may be assumed everywhere in the domain. Introducing electric field dependence of the gradient potential and well height coefficients in the free energy function allows the model to capture electrocapillarity at the interface."

Jan 1, 2001

By Leonardo Mota, Lucas L. da Costa, Milton B. Filho, Sergio N. Monteiro, Helion Vargas, Tammy G. R. Portela da Silva

"A natural biofoam extracted from the buriti palm tree has shown characteristics for potential substitution of synthetic foams. In the present work, a photoacoustic thermal characterization was performed on buriti biofoam samples. An open photoacoustic cell technique and a photothermal rise method performed under continuous laser illumination were employed in order to determine the thermal diffusivity and the specific heat capacity of such material. In addition to their intrinsic values (finger print), these physical parameters represent the light-into-heat conversion efficiency and the amount of heat stored per unit volume, respectively. The results showed that the buriti biofoam presents thermal properties that permit its use as an effective insulation material.IntroductionSolid foams are very light materials with increasing engineering applications [1]. A natural biofoam obtained from the petiole of the buriti palm tree (Mauritia flexuosa) has been recently investigated [2-4]. The evaluation of the buriti biofoam properties and the characterization of its microstructural aspects have shown that this biofoam has a potential as a new engineering material with very low density. Additionally, its reduced open porosity and low absorbed humidity revealed a promising material for packing and floating applications. In fact, this buriti biofoam, extracted from the palm tree natural of the north region of Brazil, is being used by the low income population as a modest substitute for Styrofoam® [1].As a potential insulating material, the buriti foam needs to be characterized in terms of its thermal and acoustic properties. A preliminary investigation [3] on the thermal behavior of this natural biofoam by thermogravimetric analysis, TGA, and its derivative, DTG, as well as differential scanning calorimetry, DSC, revealed parametric conditions associated with water loss and structural decomposition. Both the surface humidity and the release of hydration water were determined. Different decomposition events were attributed to both, more rigid as well as to more flexible molecular segments. Table 1 depicts technical data obtained so far for the buriti biofoam. These data are compared to those corresponding to Styrofoam®."

Jan 1, 2011

By C. M. Dentan

Conventional testing of crude kaolin ores emphasizes physical properties as they relate to end uses of kaolin products. This approach to evaluating crude ores does not reveal the basis of behavioral differences between typical coarse and fine kaolins from central Georgia. Optical and scanning electron microscopy in combination with XEDS have been employed to characterize both coarse Cretaceous and fine Tertiary kaolin in order to shed light on the reasons for the gross differences in their properties. Routine evaluation of various parameters was also carried out. Bulk densities were 1.48 g cc-l for the coarse clays and 1.53 g cc-1 for the fine clays. Surface areas were 15 m2 9-1 and 25 m2 9-1, respectively. Brookfield viscosities were low for the coarse clays at 70% solids, and high for the fine clays. The situation was reversed for Hercules viscosities. Sixty percent of the coarse clays had particles of less than 2 um and the fine clays had 90% less than 2 cm. Micrographs of thin sections prepared from blue-dyed epoxy-impregnated crude ores and of SEM fabric samples demonstrated vivid differences in texture. Cretaceous kaolins appeared to be completely recrystallized residual products of former aluminous sediments, while Tertiary kaolins retained their essentially sedimentary character. Differentiation of the coarse and fine kaolins is rapidly accomplished by both optical and scanning electron microscopy, and should be considered a valuable analytical technique in evaluating kaolin ores.

Jan 1, 1981

By M. Kawakami

In relation to the designing of a new-type blast furnace, the reaction of carbonaceous materials with CO2 is expected to occur at as low temperature as possible. In order to get a highly reaetive carbonaceous material at low temperature, the reaction kinetics was investigated by measuring such quantities as the reaction rate from weight loss, the amount of CO adsorption and specific surface area by BET method. The reaction rates were large in the order of the Bintyo char, metallurgical coke, graphite and glassy carbon. If the rate was converted to the rate per unit area, however, those of the Bintyo char was smaller than that of graphite. Thus, it is suggested that the rate of the Bintyo char is influenced by the pore diffusion of CO2. The rate had a positive relation with the amount of CO adsorption, showing that the rate determining step would be the desorption of CO from the active side on the surface. The rate independent of surface area was derived, combining all the obtained data.

Jan 1, 2003

By Yuanbo Zhang, Daoyuan Zhang, Youlian Zhou, Guanghui Li, Tao Jiang

"Modified humic acid (MHA) has been developed by Central South University (CSU) and authorized in China. It has been reported that MHA is an effective binder for oxidized pellets prepared from specularite concentrates. In this research, effects of MHA binder on roasting behaviors of the specularite pellets are studied. MHA is an organic binder, containing much carbon, hydrogen, oxygen, etc. During the roasting, MHA can provide some heat because of combustion of hydrocarbon, which is beneficial for the recrystallization of Fe2O3 in the specularite pellets at high temperature. Simultaneously, part of hematite particles within the pellets are firstly reduced to magnetite, then, magnetite is oxidized into secondary hematite, which obviously improves the roasting performance of specularite pellets.IntroductionOxidized pellets have been widely used in steel production as a kind of high quality burden for blast furnace ironmaking [1]. In recent years, production of oxidized pellets is developing very fast. Therefore, the supply of high quality magnetite concentrates, which is the most suitable for pellet production, becomes scarce. It is imperative to pursue new alternative materials for oxidized pellet production [2]. Specularite concentrates have attracted widespread attention due to the advantages of high total Fe grade and low impurity content. However, due to the poor ballability and firing performance, specularite has not yet been widely applied into pellet production [3, 4]."

Jan 1, 2012

By Yang Guangqing, Shao Jiugang, Zhang Jianliang, Wan Dan, Fu Yuandi, Guo Hongwei

"Resource of metallurgical coke is becoming scarce, and although coke can be partially replaced by pulverized coal injection, there are many restrictions for further increase in coal ratio. Mixed charge of ore and lump coal from top to replace more coke was studied in this paper. Softening-melting property of the burden was affected by charge of lump coal. Softening-melting properties of mixed charge of ore and coke, mixed charge of ore and lump coal were tested respectively. Results show: the property of the burden mixed with coke is superior to the burden mixed with lump coal; lump coal would not deteriorate softening-melting property of the burden and some of them can even improve softening-melting property of the burden. Top charge of lump coal would not deteriorate softening-melting process, and this should be a new way to increase coal consumption to decrease coke rate.IntroductionThe blast furnace is still the predominant process for the reduction of iron ore and will probably remain so for the next decades. Metallurgical coke is becoming scarce and expensive, so the cost of hot metal can be decreased by reducing the consumption of metallurgical coke[l]. Coke can be partially replaced by pulverized coal injection, currently the highest rate of pulverized coal reached 266kg/tHM, most of blast furnace PCR is about 150kg/tHM, and it is very difficult to further increase of PCR. Nut coke is charged into blast furnace mixed with iron ore, not only for improving utilization of metallurgical coke, but also for lowering the coke rate. Presently the majority of blast furnaces in the world use nut coke although its amount is very different: from 10-20 to 70--100 kg/tHM and more[2-4].The effect ofnut coke in blast furnace is extensively researched, and the main conclusions recommend: to improve gas permeability of cohesive layer in blast furnace, to promote reduction of iron burden, protect metallurgical coke from the solution in the shaft due to higher reactivity of nut coke. There is no special requirement for the strength of nut coke[5-8]. Nut coke is also used for sintering fuel, which may lead to the shortage of the nut coke charging into blast furnace. So lump coal mixed with iron ore is considered to be charged into the blast furnace, not only to reduce the cost of grinding coal, but also to increase the use amount of coal."

Jan 1, 2013

By I. Ohnaka

Although many works have been reported on the semisolid casting, the mold filling behavior of semi-solid alloys has not been so well understood. This paper compares the physical and numerical simulation results on the mold filling behavior. Physical simulation was performed by using solid-water mixture. The numerical simulation was made under the assumption of one phase flow with an effective viscosity. It was found that the solid particles stabilize the flow greatly if the kaction solid exceeds about 0.4, because viscosity increases greatly. The overall flow behavior can be estimated by the numerical simulation. Interesting flow behavior was also found which can not be observed in the case of one phase flow and which is difficult to simulate by the one phase flow assumption.

Jan 1, 1997

By James A. Sommers

Combustion of niobium nitride powder in a stream of oxygen results in several niobium oxide phases, depending upon reaction parameters. Under rapid oxygen flow, the oxidation produces a molten mass which coalesces into droplets of ca. 2 mm dimension and effectively quenches to leave NbO2 and other lower oxides of niobium, despite the ambient atmosphere of oxygen. A preliminary survey of reaction parameters which govern the split between reduced and oxidized products is presented. This technique offers novel synthesis means for binary oxides when mixtures of NbN and other materials are combusted together, since the niobium moiety is generated in a molten state.

Jan 1, 1995

By S. Tandon

Equilibria studies of selenium distribution for sodium-borate slags were initiated at 1473k under reducing condition as a function of slag composition and alloy composition. The Se distribution coefficient (% Se in slag/% Se in metal) increased from 0.4 to 2.9 with increase in basicity (0.53 to 0.86) for Cu-0.446% Se alloy. However, the results are not very useful from industrial application viewpoint. Therefore, in order to improve the distribution of Se, CaO (10% to 50%) was added to the sodium-borate slag of basicity 0.864. On addition of 502 CaO, the distribution coefficient increased roughly by 100% for slag composition - 44.5% Borax, 22.2% Na2C03, 33.3% CaO and Cu-0.44677 Se alloy. Further, the value of this distribution coefficient has been found to increase by an additional 80% on addition of 20% CaF2 to the above slag for all Cu-Se alloy compositions. Also with increase in initial concentration of Se, the distribution coefficient has been noted to increase.

Jan 1, 1992

By Chen Ya

Layered LiMn0.5Ni0.3Co0.2O2 was prepared from Mn(NO3)2, Ni(NO3)2, Co(NO3)2 and LiOH by co-precipitation and solid state reaction. XRD, C-V and galvanostatic charge-discharge methods were used to examine the structural and electrochemical characteristics. The LiMn0.5Ni0.3Co0.2O2 delivered a high discharge capacity of 167 mAh/g between 2.5 and 4.3 V with excellent cycling stability.

Jan 1, 2006