Search Documents

By M. D. Lawton, P. Steen

"Drilling results from the established levels at AngloRouyn Mines Limited had indicated inadequate tonnages to meet the planning schedule. It was decided to develop the main zone of the orebody below the bottom working level of the mine. The orebody dips north at an average of 50 degrees and plunges to the west at about 10 degrees. Due to the need for rapid development of this area, a decision was made to use trackless equipment.This paper describes the method used and highlights the use of small 5-ton diesel trucks as carriers for the 2-cu.yd LHD machine. The method achieved advances of about 1,000 feet per month, at a dip of 12 degrees over a length of close to 2,000 feet, using as few as 20 men per day."

Jan 1, 1971

By Yasuo Iizuka

We have had studied CO oxidation on unsupported Au powder (mean particle size, ca.100nm) manufactured by evaporating ultra high purity gold metal (>99.99%) in inert gas and reported that it showed some activity after oxidizing pretreatment in O2 at 423 K?453 K. However, recent XPS analysis of the Au powder revealed that it contains much amount of impurity metals such as Ag and In at levels which far exceed those expected from the impurity level of raw gold metal in the bulk. Several samples of Au powder containing different amount of impurity metals were prepared to examine whether the activity depends upon the existence of surface impurity or not. Activity measurements were performed at 273 K after undergoing the powder under various pretreatment conditions. Although the activity of Au powder varied to some extent according to the pretreatment condition, it is strongly correlated to the surface concentration of Ag. Such dependence was not found for In, indicating that the activity of unsupported Au powder is mainly due to the existence of Ag in the surface layer. The activity attributable to ?particle size effect? was not recognized for Au powder with a mean particle size larger than 80 nm.

Oct 1, 2003

By Y. M. Shneerson, I. V. Fomenko, M. A. Pleshkov, E. A. Ospanov, A. A. Shakhalov, S. S. Naboychenko

Low-grade copper concentrates (with copper content less than 20%) often contain impurities such as arsenic, zinc, lead, mercury, antimony and bismuth. The pyrometallurgical treatment of such concentrates is associated with several problems, which will ultimately affect the cost and the quality of copper cathodes as well as by-products. SRC Hydrometallurgy proposed a complex hydrometallurgical technology which allows the removal of impurities and the enrichment of low-grade copper concentrates to a quality which will be more suitable for pyrometallurgical processing. Laboratory batch tests and pilot plant results for the pressure leaching steps are shown in this paper. The key parameters of the leaching steps were determined and optimized. The quality of possible by-products were also determined. The developed flowsheet includes two pressure leaching steps: pressure oxidation (POX) and hydrothermal alteration (HTA). Both operations are carried out at 170°C with subsequent flotation of POX and HTA residues and recovery of copper, zinc and lead into separate concentrates for further processing. The development of the flowsheet was based on the Balkhash Zinc Plant (Balkhash, Kazakhstan), which had been non-operational since 2009. The developed flowsheet for processing of low-grade concentrates will utilize 80% of the existing equipment of the Balkhash Zinc Plant, thus leading to a significant reduction in required capital expenditure. INTRODUCTION As the age of copper mining operations advance, copper grades continue to diminish and impurity levels increase. Therefore, copper producers are forced to look for new innovative hydrometallurgical technologies which are able to handle low-grade raw materials and solve problems associated with impurities in an economically justifiable way. New technologies allow to extract valuable components selectively and to process low-grade concentrates which had previously been marked as non-technological and economically unviable. Hydrometallurgical technologies for processing of copper-containing materials can be divided into two main categories: chloride and sulfate (atmospheric, autoclave and bacterial) based technologies. Since the 1970s, many autoclave techniques for the processing of copper-containing materials have been developed and implemented (Naboichenko, 2002; Dreisinger, 2005; Habashi, 2009; Shneerson, 2011). The mineralogical composition of the ore (or concentrates), geographical location of the deposit, distance from industrial areas, availability of existing treatment facilities, availability of skilled labor, cost of electricity and cost of neutralization are some of the factors which are usually considered when the appropriate technology is selected (Halbe, 2002).

Jan 1, 2019

By A. F. Laurin, A. L. Dorr

"Because of its wide areal extent, its numerous lithological facies and its high degree of metamorphism, the Quebec portion of the Grenville province has only partly been explored and prospected. Rock types that are economically among the most interesting in the Grenville are those of mafic and ultramafic compositions, because of their great potential for coppernickel and chromium-platinum. The peculiar mode of occurrence and the distribution of these igneous masses in which copper-nickel mineralization is known to occur indicate' two common geological features: (1) aerial photographs and/or topographic maps strongly' suggest close spatial (and possibly temporal and genetic) association of most of these mineralized mafic and ultramafic intrusions with circular structures; (2) when plotted on a large-scale map comprising the Quebec portion of the Grenville, these circular structures fall along two lines which could correspond to major tectonic features. Even though the genetic links among the mineralized mafic-ultramafic masses, the circular structures and the linear features are not yet fully understood, their associations are believed to be empirically valid and should therefore be used as geological tools by those interested in exploring the Grenville for copper-nickel and possibly chromium-platinum deposits. It should be noted that these mafic and ultramafic bodies do not appear to be spatially related to anorthosite complexes."

Jan 1, 1971

By Abani R. Samal

The Fe assay values from the diamond drill-holes within a magnetite deposit of magmatic origin are utilized in this study. Only assay data from the unoxidized magnetite mineralization was utilized. The data from the overlying hematite mineralization zone was not used. A threedimensional block model estimated using ordinary kriging (OK) is used for analysis purposes. To estimate the non-linear standard deviations (s) and the confidence intervals (CI) of block estimates a discrete Gaussian variogram model is used in this project. The change-of support coefficient (rv) and the block-support correction are used in the ?block-anamorphosis?. A new calculated value of rv is 0.7283, implies that its influence in the block-anamorphosis is not significant. The CIs are calculated from the block-gaussian variables; then back transformed to the raw values. At 95% probability, the CI for the kriged block estimates of Fe values are calculated using Gaussian kriged estimates of the Fe and the corresponding standard deviations (Gaussian). The results indicate that the block estimates with a high influence from relatively small amount of samples can be identified as high-risk estimates.

Oct 1, 2009

By A. Y. Senchenko, S. G. Rybkin, A. V. Aksenov

In gravity processing of gold-containing ore the target produced concentrate which is high gold grade primary concentrate contains a significant amount of cassiterite (SnO2). The plant attempts aiming at concentrate processing using a standard pyrometallurgical technology did not provide any positive results. The present paper is dedicated to development and testing of improved technology for pyrometallurgical processing of rich gold primary concentrate with high cassiterite content. According to material composition study primary concentrates produced at the plant contained 1.5–2.0% Au, 0.1–0.3% Ag, 55–65% SnO2, 20–25% Fe2O3, and 10–15% Fe3O4. The developed technology included alkaline nodulizing of primary concentrate mixed with sodium hydroxide and carbonate at 350–650°? with cake production. In blend nodulizing stannum and iron passed into sodium stannate (Na2SnO3) and sodium ferrate (NaFeO2) respectively. The blend of cake and fluxing agents was smelted at 1,150–1,200°? resulting in dore gold and slag production. Sodium stannate with 360°? melting point is well dissolved in slag system Na2OSiO2- B2O3-CaO. During plant tests 18.5 kg of high gold grade primary concentrate were processed, 1350 g of dore gold and 75 kg of slag were produced. Dore gold contained 16.5% Au, 0.95% Ag, 78.0% Sn, 3.1% Fe. Slag contained 12.4 g/t Au, 6.7 g/t Ag, 9.8% Sn, and 5.6% Fe. Gold recovery to target alloy was equal to 99.58 %, 87.8% of Sn passed into slag. This new technology was accepted for application at the plant.

Jan 1, 2016

By Z. Mubarok

An overview of the problems encountered the electrorefining of copper anodes containing high levels of nickel and antimony is presented. Our investigations have been focusing on the passivation behaviour of the anodes with high contents of Ni, Sb, Sn, and Pb, the formations of kupferglimmer and floating slimes. The results of linear voltammetry, chronopotentiometry and electrolysis test revealed a noticeable lower resistance of the anodes to passivation in comparison to those with lower contents of Ni, Sb, Sn, and Pb. Anode containing kupferglimmer exhibited oxygen gas evolution during the passivation state. Scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) indicated that tin can replace and/or join antimony in the kupferglimmer structure. Under specified experimental conditions, floating slimes precipitations took place with high Ni, Sb, Sn, and Pb anodes prior to the end of one anode period.

Jan 1, 2007

By W. M. Williams

"Although manganese is a metal virtually unknown to the layman, it is hardly necessary to point out to the engineer the importance of manganese in modern metallurgy, an importance intimately linked with iron (and steel), the basic materials of engineering construction for hundreds of years and certain to remain so for long into the future. World steel production will approach and perhaps reach 1 billion tons/year in the 1980s; with a manganese content between 0.5% and 1 % in ordinary steels, and more in specialty steels, manganese use worldwide will soon approach 15 million tons annually. Manganese was discovered and isolated in Sweden in 1774 by Karl Wilhelm Scheele (who also discovered molybdenum), but the element was only of scientific interest for several decades. By the early part of the nineteenth century, however, manganese oxide had become commercially available and was in use for colouring glass and for the production of chlorine. Commercial application in metallurgy appears to have been limited to the manufacture of crucible (or ""cast"") steel, a highquality product made by carburizing wrought iron, and melting it in small batches to make ingots which could be rolled and used for special applications, e.g. for the manufacture of fine tools or for ""steeling"" the cutting edges of implements such as wrought iron axes and chisels.* However, it was not until Bessemer's epoch-making invention of cheap steel in 1856, and the dramatic expansion of the steel industry thereafter, that manganese assumed the importance that it holds in modern steelmaking."

Jan 1, 1999

By Ron Jessulat

"IntroductionBrunswick Mining and Smelting Corp. Ltd. is a IO 500 tid base metal producer. Development is carried out by Jarvis Clark MJM-21 3-boom development jumbos, using Tamrock E400, 410 and 550 pneumatic drills. Typical drift size is 13 ft by 18 ft with a 12-ft advance per round. Blast holes are 1 ½ in. in diameter while reamed holes are 3 in. in diameter. AN/FO is the principal blasting agent, being loaded by C-I-L model60R intermediate loader. The detonators are NONELS and DETINELS. Sulphide dust explosions occur during blasting when dusts from certain minerals such as pyrite and pyrrhotite are ignited by name from the detonating shots. The result is a secondary unwanted explosion with a characteristic shock wave and name front that are very destructive to mine services such as ventilation ducting, electrical cable, and ventilation control doors.A typical reaction in the Brunswick orebody occurs according to the chemical formula:4FeS 2 + IIOs-2Fe2O3 + 8SO2 + 3458--(Enright , 1988)The hematite (FeO3) is deposited as a red dust in the blast area while the toxic sulphur dioxide gas (S00 contaminates the underground workings . The presence of S02 gas disrupts production until it is purged from the area by the mine ventilation system or dissipates slowly in those areas where the vent ducting has been melted by the name front or torn down by the shock wave.Sulphide dust explosions exact a high economic toll. Direct costs in damaged materials and wages are probably exceeded by the value of lost production and disruption to the mining cycle. In addition, the health and safety concerns associated with sulphide dust explosions cannot be ignored."

Jan 1, 1993

By Feng Tianran, Lu Shijie, Shen Zhengchang, Han Zhibin, Tan Ming

"As a kind of non-metallic material, high-purify quartz sand has been widely used in many fields. Flotation is a popular way to process quartz sand. But it is in difficult position for flotation to get high-purify quartz product due to large amount of coarse particles contained in the feed. In this paper, a design principle of special flotation cell for high-purify quartz sand has been put forward base on ore property analysis and laboratory test, and the pilot scale special flotation cell has been developed to meet the requirement of the quartz sand flotation process. The special flotation cell for high-purify quartz sand is featured by middle positioned impeller, false bottom and draft tube, which could decrease the rising distance of mineralized bubble and strengthen the circulation capacity of the lower part of the flotation cell. Hydrodynamic study indicates that high air dispersion degree and strong lower slurry circulation could be produced by pilot scale special flotation cell, which is helpful to create a suitable hydrodynamic environment for quartz sand processing.INTRODUCTIONNatural quartz is a non-metallic mineral, which is widely used as raw material in multiple industry process (Shifu, 2006). High purity quartz, especially containing more than 99.9% silicon dioxide, is characterized by high temperature resistance, small thermal expansion coefficient, highly insulating and so on. The demand of high purity quartz has been rising along with social and economic development, now high purity quartz is widely used in the field of photovoltaic industry, electronic information, communications and aerospace industry.Quartz is a kind of main rocking-forming minerals in the nature. There are seven genetic types, such as natural crystal, quartz sandstone, quartzite, vein quartz, konilite, natural siliceous sand, granite quartz (Baolei, Shuilin, & Dianchao, 2012). The natural crystal is primarily used as raw material to refine high purity quartz, but it is not available for two reasons. On the one hand, the natural crystal is extremely expensive and poor in resources reserves, which can not satisfy the need of large-scale industrial production. On the other hand, the chemical component of natural crystal is instability, it may lead to low stable product performance in large industrial applications, and it is also difficult to achieve raw materials standardization. Therefore, there are a lot of studies to search for other technological methods to obtain high purity quartz from other genetic quartz types."

Jan 1, 2016

By Sergio Fuentes

During the past fifteen years, mines utilizing the block caving method have improved performance and systematically reduced total mining costs. This paper describes improvements in mine design, mine planning and mine management, including methods enabling the Chilean and International mining industry to ensure cost savings and productivity growth while using the block caving method. These improvements have encouraged the re-evaluation of underground operations at operating and closed open pits, and challenge surface mining applications as the only low cost mining method. This paper describes a strategy to estimate the optimum open pit to underground transition time during the life of a mine.

May 1, 2003

By Bob Rappolt

Discussion Points Part 1: Global Mining Industry/Related Issues ? Historical Metal Price Trends. ? Historical LME Metal Stockpiles. ? China?s Demand for Metal. ? World Population Growth, Demands and Development. Discussion Points (cont?d) Part 2: Canadian Mining Industry ? Where are we? And where are we going? ? What progress have we made in the past 20 years regarding: ? Safety -Employee Levels ? Labour -Relative Compensation ? Productivity - Technological Advance ? Where do we stand regarding mineral production? ? What does the future hold for us?

Apr 1, 2005

"The Dome Mine, located in South Porcupine Ont. has been in operation since 1910 and is owned and operated by Placer Dome Inc. The current milling facilities were constructed in two phases with the first being commissioned in 1982. It consists of a grinding, gravity separation, thickening, and leaching circuits. The second phase was commissioned in 1988 with the addition of the CIP, stripping, electrowinning, and carbon regeneration circuits.It is now common practice in the gold processing community to add liquid oxygen to leach circuits to increase both recovery and kinetics. Along with these benefits the metallurgical group at the Dome realized the potential to replace compressed air with liquid oxygen as a source of oxygen for the dissolution of gold. A plant trial of liquid oxygen was undertaken during the fall of 1991. The results of this first test were favourable enough to warrant further investigation, and a second plant trial was conducted in December 1991.The data generated as a result of each trial revealed that oxygen could be economically substituted for compressed air as a source of dissolved 02. The energy savings in required horsepower enabled a rapid payback period. Thus the project was approved in the spring of 1992 and l should be operational during the final quarter of 1992. INTRODUCTIONIn a continuing effort to reduce operating costs and improve recovery at the Dome mill it was decided to investigate the feasibility of adding liquid oxygen (02) to the leach circuit. It is now common practice in the gold processing community to add 02 to the leaching process to increase both kinetics and recovery. It was anticipated that an increase in kinetics would allow us to eliminate one or more leach tanks while maintaining acceptable recoveries. The metallurgical group felt that along with these benefits, the potential was also there to reduce power consumption through the reduction in the processing of compressed air which is quite costly (12 cents/1000 cubic feet per minute in 1991)."

Jan 1, 1993

By Shinji Muraishi, Shinji Kumai, Yasutaka Kedo, Takashi Kambe

"Magnetic pulse forming (MPF) is one of the extreme high-speed forming processes. A metal sheet which is accelerated by electromagnetic force is collided onto a mold and fine and sharp details of the product can be obtained. The deformation mechanism of the MPFed metal cannot be understood only by the microstructure observation of the deformed metal. The deformation behavior of the metal should be investigated also by considering the local microstructure change with strain, strain rate and temperature change during deformation. Numerical analysis is an effective method to achieve this requirement. In this study, pure Al and Cu sheets were deformed by MPF. Impact velocity of the metal sheet was calculated by using ANSYS Emag-Mechanical. Based on the obtained impact velocity, the deformation behavior of the metal sheet was reproduced, and local strain, strain rate, and temperature were analyzed by using ANSYS AUTODYN. The relationship between the local microstructure change of Al and Cu sheets and the deformation parameters was examined.INTRODUCTIONMagnetic pulse forming (MPF) is one of the high-speed forming processes using electromagnetic force. Fine and sharp details of the product can be obtained, and springback after deformation is extremely reduced in comparison to the conventional forming processes(Psyk, Risch, Kinsey, Tekkaya, & Kleiner, 2011). Figure 1 shows a schematic diagram of MPF. A metal sheet is placed over the coil in the discharge circuit. The discharge current runs through the coil, and magnetic fieldis producedaround the coil. An eddy current is inducedin the metal sheet. Interaction between magnetic field and eddy current creates electromagnetic force. The metal sheet accelerated by electromagnetic forcecollides ontothe mold. Forming is completed in a few tens of micro-seconds.MPF is suitable for metals with a high electrical conductivity like Al and Cu.The MPFed metal may have characteristic microstructure because of high strain rate deformation."

Jan 1, 2018

By R. H. Keyes Duval

"The one point left off the table was pumping costs, i.e. the cost of pumping to the cyclones.At East Malartic 5 x 5 S R L pumps that had been used to pump the classifier overflow were used to pump the rod and ball mill discharges to the cyclones. Maintenance costs on the pumps rose from $105 in 6 months to $1000 per month. The pumps had to be operated at 1150 rpm and impellers lasted only 5 to 6 days. These pumps were replaced by 6 x 6 S R. L. pumps operating at 825 rpm, but at this speed the coarser sands settled and plugged the pipe lines and the speed was increased to 925 rpm. The maintenance cost is now $100 per m::rnth which is 0 003 cents per ton milled. The impellers now last 1 month and the casing linings 6 months.Density meters are often used on cyclone overflows and sometimes on the cyclone feed. Haliburton weighted tube density meters are used in some plants. They are cheaper than the radioactive density controller, $2500 as compared to $ 6000The angle of the discharge spray from the apex can be used to judge the quality of perform1nce of a cyclone.For ordinary metallurgical applications the inside slope of the cyclone is not too important but for fine separation steeper slopes are used.The cyclone is a versatile tool and will handle considerable variations in feed tonnage - probably up to 15%. Above this variation the number of cyclones used has to be increased or decreased or the tonnage fed to them has to be adjusted"

Jan 1, 1965

By C. Barnett

"A description of the Geco orebody has been given by W .L. Brown and R.C.E. Bray (1). The mill flowsheet and equipment were described by M.J.S. Bennett, D. Wild and C. Lawton (2). Mill capacity is now 4, 150 tons per operating day of copper, silver, zinc and lead ore. A recent flowsheet has been published in the - Canadian Mining Manual (1966).Soon after the start of production in September 1957, it became apparent that large tonnages of sand would be required by the mine for backfill pruposes. Initial experimental work on the preparation of sand fill from the flotation tailings was begun in late 19 59. Cyclones of local manufacture, in a variety of sizes, were tested quite successfully. There were, however, several obvious advantages with some of the custom-built cyclones and a recommendation was obtained from the Techniquip Company. A single Krebs D-10-B cyclone was tested experimentally in 1960.INITIAL TESTWORKExperimental results showed that with our relatively coarse grind (in the order of 53 % minus 200 mesh) 75 - 80% of the flotation tailings could be recovered as backfill sand with one stage of treatment. Percolation rates of four inches per hour were obtained with cyclone inlet pressures in the range of 20 - 25 psi and feed densities of 20 - 23% solids."

Jan 1, 1968

By John Blackshaw

NEW sources of supply of tungsten concentrates became necessary when the flow from the Far East was blocked in 1942. In Canada, one source has been noted in the workings of the Hollinger mine at Timmins, Ontario. For many years, a small amount of scheelite had been removed with the gold ore, and an appreciable tonnage of scheelite still remained in the mine. At the request of the Dominion Government, a plant was built to recover this scheelite in the form of a concentrate that could be used by the alloy-steel industry without further preparation. The plant began operating early in March, 1942, and a small tonnage of ore, carrying scheelite and gold values, has been treated daily since then. The possibility of recovering the scheelite had been considered on several previous occasions. Each time the proposal had been given up because the total profits from the enterprise were estimated to be insufficient to repay the capital cost of building the recovery plant. At the time the plant was built, additional information had been gathered about the tonnage and grade of the scheelite ore in the mine, and several thousand tons of ore grading higher than 0. 25 per cent WO3 (tungstic trioxide) were known to be available.

Jan 1, 1943

By Caitlyn J. McKinley, Ahmad Ghahreman, Maziar E. Sauber

Ever-growing global needs for critical metals, such as rare earth elements (REE), and base metals, such as copper and nickel, and their environmental impact motivated the pursuit of sustainable flowsheets. Regeneration of hydrochloric acid in chloride-based leaching flowsheets as a critical unit operation is an example of such endeavours. This study presents an efficient hydrochloric acid regeneration method from a magnesium chloride solution waste by addition of sulphuric acid in relatively low temperatures. The effects of temperature, initial magnesium chloride concentration, amount of sulphuric acid added, and airflow are examined. Experimental work are focused on temperatures between 80 and 95°C, initial magnesium chloride concentrations of 2 to 5 M, 100% to 220% stoichiometric sulphuric acid additions, and airflows between 200 to 600 mL/min. The developed technology recovers hydrochloric acid at a high rate and concentration with a relatively small environmental footprint. INTRODUCTION The mining and metals sector is under increasing environmental and economic pressure to make more efficient use of chemical reagents and energy in the production process. This affects several areas of process and flowsheet design such as the selection of the most appropriate unit operations and the overall design of the process steps paying heed to sustainability. Owing to the inherent inefficiencies of physical and chemical processes used in the mining industry, there will be materials and streams generated that are not a desirable part of the envisaged flowsheet. Thus, methods are implemented to recover and recycle such effluents. If the recovery and recycling are not economical, then procedures are followed to neutralize and dispose these effluents. In many cases, these effluents are potential contaminants or hazardous materials, and their disposal should be looked at in a much larger context. The safe management of the contaminants and hazardous effluents is a daunting problem in the mining industry and is fraught with technological, economic, social, and political challenges.

Jan 1, 2019

By C. -S. Xie, J. -H. Kong

The microstructure and mechanical properties of X80 hot-rolled thick steel strips with a thickness of 17.5mm produced in Wuhan Iron & Steel Company (WISCO) are introduced in the paper. The steel strips as fabricated through proper thermomechanical processing (TMP)/ on-line accelerated cooling (OLAC) processing have shown high strength and toughness, low brittle transition temperature, good weldability, and high Shear Area (SA) percentage in Drop Weight Tear Test (DWTT). The microstructure of the steel strips is characterized with mainly acicular ferrite, and fine dispersed Martensitc-Austenite (M-A) phases. It is determined that the mechanical properties are improved due to the presence of the fine M-A phases and precipitates, which could be formed by reducing the finish rolling and coiling temperatures.

Jan 1, 2005

By Sarah Bélair, Denis Beltrami, Deka Moussa Ragueh, Valérie Weigel

"Scandium is a highly valuable element belonging to the rare earth elements (REE) but it has different chemical and physical properties from those of lanthanides. This metal is generally used in aluminum-scandium alloys and in fuel cells but the development of its market is slowed down by its high price (more than 1000 US$/kg for a 99.0% grade product). Indeed, the low scandium content in the continental crust (an average of 22 ppm) and the difficulties to extract it selectively from solutions containing high impurity concentrations increase the cost of the recovery processes. Nowadays, scandium is primarily recovered as a byproduct.ERAMET is developing a hydrometallurgical process in Gabon (Mabounié) in which the scandium content in the deposit reaches 10 to 100 ppm. The Maboumine project consists in the extraction and purification of uranium, niobium, tantalum and REE from Mabounié ore. In the frame of this hydrometallurgical project, ERAMET had also studied the feasibility to recover scandium as a byproduct. During the ore leaching, uranium and rare earth elements including scandium are solubilized into the pregnant leach solution (PLS). Among the various methods investigated to recover scandium from the PLS, liquid-liquid extraction using Primene JM-T as extractant was chosen and tested first at laboratory scale and then at pilot scale. Selective stripping of the loaded organic was carried out by using phosphoric acid solution, allowing the selective recovery of scandium from thorium and zirconium partially extracted from the PLS by Primene JM-T under the process conditions."

Jan 1, 2016