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By M. A. Tomlinson, A. Di Feo, T. C. Cheng

"Goldcorp is evaluating the potential for economic reprocessing of historic tailings at several sites, including the Aunor A facility located in Timmins. The overall project is investigating the ability to recover value, remove sulphide minerals and alternative tailings re-deposition strategies. Desulphurization of tailings will eliminate potential acid generation while improved tailings re-deposition could reduce long-term liabilities and closure costs. Through a task-share project between CanmetMINING and Goldcorp, tailings obtained from Aunor A site have been characterized using mineral association analysis and diagnostic separation techniques. The selected tailing samples contain about 2 g/t of gold. Mineralogical analysis has identified coarse agglomerates bound with gypsum and significant free gold, confirmed by high recoveries in cyanide leach tests. However, despite no evidence of surface passivation on the minerals, conventional flotation techniques were found to be ineffective in concentrating gold or sulphides due to the high fines content and highly agglomerated particles.INTRODUCTION Aunor Mine is one of the historic mines that belongs to Porcupine Gold Mines (PGM) in Timmins, Ontario. PGM has undertaken an extensive mine closure program to remediate the legacy and closed mines with the funding supported by operating mines since 2006. Over the course of 100 years of operation in the Porcupine camp, it is estimated (Stevens et al., 2013) that about 130 million tonnes of tailings have been generated. Aunor Mine produced 2.5 million troy ounces of gold between 1940 and 1984, while processing over 7.6 million tons of ore. The original gold grade of Aunor Mine ores was about 10 g/t. With 95% gold recovery at the time, an estimate of 0.5 g/t of gold remains in the Aunor Mine tailings. Aunor Mine has two tailings impoundment areas: designated as Aunor A and Aunor B. The two sites are similar in size, about 7 hectares each. The amount of tailings in the Aunor A site alone is about 3.2 million tonnes. In 2017, bulk tailings were sampled from five designated locations in Aunor A. They were characterized using mineral association analysis and diagnostic separation techniques. The bulk tailings samples contained about 10% total sulphur, 10% iron, 2% arsenic and 2 g/t of gold. The prime objective of this collaborative work between CanmetMINING and Goldcorp is to facilitate the timely development and deployment of innovative tailings reprocessing solutions, specifically in the areas of desulphurization, and recovery of metals. This work targeted specific tailings of interest to Goldcorp which goals are to improve its environmental footprint and to reduce long-term liability. Thus, it is imperative to look for innovative reprocessing options that can overcome not only technological challenges but also achieve economic benefits to offset the costs associated with reprocessing the tailings. Moreover, the greater goal is to demonstrate and deploy tailings reprocessing solutions to solve one of the industry’s most difficult challenges for a sustainable mining industry in Canada."

Jan 1, 2019

By Karl J. C. Harries

"The Table of Contents that follows is only an example and is the Table of Contents from an actual negotiated agreement. It is merely intended to show how an agreement might be set out and the nature of possible provisions. As a negotiated agreement the format was dictated by the negotiations. It is not offered as a precedent of what should be contained in a joint venture agreement (“JVA”), the “proper” sequence of Articles, or a complete listing of the contents of joint venture agreements generally. The set-up used for an agreement should be decided by the parties and be one they consider flows in a logical and workable sequence. This example sets out the “deal” first, followed by the provisions relating to how work is to be carried out and then by administrative provisions necessary to make the agreement work. If you are more comfortable with, say, having the Committee provisions at the beginning, by all means have it drafted that way -- you are going to have to live with the agreement and work under it.Notes:1. The Table of Contents provisions appear in bold print. The italicized sections are annotations, which have been provided in some cases where the heading may not clearly describe the contents. They are not intended to be comprehensive, but refer to some specific matters that are considered to be of interest or to need some clarification.2. The subject matter of many of the articles and paragraphs is discussed or commented upon in the text of the book. Some of section cross-references have been provided. Such references are only to sections where the topic is a principal subject and no attempt has been made to provide a comprehensive indexing.3. Although this particular agreement is a three-party agreement, *B* and *C*, the Owners, are required to act as a unit (see para. 1.09. – § 8.44.), making the agreement effectively a two-party agreement. The parties insisted upon having a decision-making Committee and structuring the agreement accordingly. As is explained in § 8.11., such an arrangement is not recommended and can result in problems.5. See also §§ 8.24., 8.41. and 14.13. for discussions on tables of contents, summaries, and headings."

Jan 1, 2003

By Tom Shumka

INTRODUCTION ?The Electro-Magnetic Crack Detection (EMCD) technique is an electromagnetic inspection method used for detecting and sizing surface breaking flaws. ?It works well on structural material or welds, ferrous or non-ferrous metals. ?EMCD?s rapid scanning is achieved using a hand-held probe. ?EMCD provides reliable crack detection and sizing (length and depth). Cracks can be sized accurately. ?EMCD dramatically reduces most cleaning requirements as there is no need to clean to bare metal. ?EMCD is capable of inspection through thin metallic coatings, or through non-conducting coatings up to 10mm thick. ?EMCD allows full data storage for back-up, off-line view and audit purposes.

Oct 1, 2010

By Janos de Warga

"After a short introduction to the history of the semi-conductor theory, the paper describes the principles of electron and hole flow in the semiconducting materials, the operation of the PN junction, and the rectification process in multi-layer devices (diodes and SCR's). The various methods of purification and zone-refining of the silicon are illustrated prior to the discussion on the most commonly used junction-forming processes (alloying, diffusing, etc.). Modern device fabrication and packaging operations are illustrated. Factory testing, evaluation, electrical parameters and guaranteed rating characteristics are listed. It is explained in this paper how the various device parameters affect the electrical performance of the finished unit and how the finished unit characteristics (turn-on, turn-off time, etc.) will influence the equipment rating. In concluding, some typical items of equipment are highlighted, and the applications of these semiconductor rectifiers in the chemical, mining, pulp and paper, and steel industries, etc., are dealt with."

Jan 1, 1967

By Denis Raymond, Yvon Trudeau

"Abstract-The Orion gold mine, located 7 km northeast of the town of Malartic, Quebec, was discovered in mid-1985. Underground exploration was undertaken in 1986Ieading to commercial production in 1988. The upper part of the orebody was exploited above the 125 m level and a total of 131 090 t at an average grade of 5.31 g/t gold were extracted.This paper describes the authors' current knowledge and interpretation of the geology, gold distribution, and structure of the Orion No. 8 ore zone deposit. The deposit is an epigenetic lode gold occurrence somewhat unique in that both quartz-vein type and pyritic type of gold ore occur side-by-side. It is located within the Marban-Norlartic Deformation Corridor (MNDC) formed during a first deformation stage (D1). The MNDC is a well-defined regional structural feature in the Val d'Or- Malartic mining camp. Primary gold mineralization is associated with the D1 event and is represented by pyritized , silicified and brecciated basaltic lavas enclosed by ultramafic flow units. The ore zone is concordant with the MNDC. Felsic intrusions are spatially related with the ore zone, but their role in the genesis of the ore has yet to be defined.A second deformation event (D2) resulted in local folding, a second schistosity (S2) and reverse faulting. Gold remobilization, the formation of the gold-bearing quartz breccia and the emplacement of the main quartz vein at the No . 8 zone deposit were associated with this event."

Jan 1, 1992

By Yvon Trudeau, Deni Raymond

"The Orion gold mine, located 7 Ian northeast of the town of Malartic, Quebec, was discovered in mid-1985. Underground exploration was undertaken in 1986 leading to commercial production in 1988. The upper part of the orebody was exploited above the 125 m level and a total of 131 090 t at an average grade of 5.31 g/t gold were extracted.This paper describes the authors' current knowledge and interpretation of the geology, gold distribution, and structure of the Orion No.8 ore zone deposit. The deposit is an epigenetic lode gold occurrence somewhat unique in that both quartz-vein type and pyritic type of gold ore occur side-by-side. It is located within the Marban-Noriartic Deformation Corridor (MNDC) formed during a first deformation stage (D1) The MNDC is a well-defined regional structural feature in the Val d'Or - Malartic mining camp. Primary gold mineralization is associated with the D1 event and is represented by pyritized, silicified and brecciated basaltic lavas enclosed by ultramafic flow units. The ore zone is concordant with the MNDC. Felsic intrusions are spatially related with the ore zone, but their role in the genesis of the ore has yet to be dermed.A second deformation event (D2) resulted in local folding, a second schistosity (S2) and reverse faulting. Gold remobilization, the formation of the gold-bearing quartz breccia and the emplacement of the main quartz vein at the No. 8 zone deposit were associated with this event."

Jan 1, 1992

By Charles Amoah

Abosso Goldfields Limited has been optimizing the comminution circuit at the Damang Mine Operation for the treatment of 100% primary ore. The optimization process started at a base rate of 343 tph when treating primary crushed primary ore, and was increased to above 600 tph with partially crushed primary ore. Abosso Goldfields engaged Orway Mineral Consultants (OMC) to assist with the optimization process in 2009 and the two companies have been working together since, to further refine the process. Continuous improvement was achieved through crushing circuit modifications, changes in operating processes and grinding control system utilization. This paper discusses the improvements developed for the increase in milling capacity and improvements in final product size.

Jan 1, 2012

By Tai Sik Lee

Why ISRU into Space Exploration are important NASA and International Mission statements calls for the sustainable human exploration of the Moon, Near-Earth asteroids, and Mars Common Exploration Goals and Objectives are Strongly influenced by ISRU Extend Human Presence: Continually increase the duration and level of self sufficiency at all destinations Develop Exploration Technologies and Capabilities: Develop and validate tools, technologies, and systems that extract, process, and utilize resource to enable exploration missions Perform Science to Support Human Exploration: Characterize available resources at destinations Stimulate Economic Expansion: Encourage commercial services and create new markets, including markets for discovered resources Enhance Earth Safety: Test techniques to mitigate the risk of asteroid collisions with Earth

May 1, 2013

By Qing-hua Tian, Li-then Cheng, Xue-yi Guo

In order to recycle valuable metals from silver separated residue, a novel method using alkaline smelting at low temperature was proposed. The main factors affecting the main metal recovery such as the smelting temperature, smelting time, liquid-to-solid ratio and alkali addition were investigated comprehensively. The behavior of the main metal elements, such as Pb, Sn, Sb and Bi in silver separated residue was also discussed. The results indicated that amphoteric metals such as Pb and Sn can be smelted into the melt, while other metal elements, such as Sb and Bi were left in the residue.

Jan 1, 2011

By Martin P. Raffield

Placer Domes? Campbell Mine, situated in northwestern Ontario, is undergoing an assessment of the efficiency of the operation which is necessitated by the low gold price and a reducing ore reserve grade. A decision has recently been taken to move away from a functional based departmental structure (underground, engineering, geology, etc.) towards a team-based system where crews, engineers, geologists and supervisors are responsible for the planning and operation of a particular area of the mine. The objective is to improve communication and understanding of the goals and achievements and to ensure a forum is available for the generation of ideas. It is intended to increase the accountability and decision-making ability of the teams in an effort to achieve the mines? safety and production targets. This paper presents a critical review of the progress of this organisational change process and its successes and failures at the time of writing.

Oct 1, 2001

By H. Matsuoka, M. Kawata, K. Mitsuhashi, C. Tokoro, T. Kato

Copper sulfide minerals such as chalcocite, bornite, and chalcopyrite exhibit high floatability, thus they can be recovered as a froth product by adding only a collector in flotation process. However, when their surface is oxidized, the floatability decreases and the simple addition of collectors is no longer effective. In this case, flotation activators are required to improve the floatability. Sodium hydrosulfide (NaHS) acts as an activator for chalcocite and bornite by re-sulfurizing their oxidized surface portions. Nevertheless, the flotation conditions still require optimization in order to achieve a satisfactory recovery of copper minerals. This work addresses the study of the effect of pH and NaHS dosage on the flotation of a complex Chilean copper ore containing chalcocite, bornite, and chalcopyrite. Flotation experiments were conducted using a Denver-type flotation cell and by investigating the effect of two NaHS dosages (50, 100 g/t) and three pH values (8, 9, 10). Following this process, the surface interaction between the minerals and NaHS were analyzed using zeta potential measurements. INTRODUCTION In recent years in the mining area of metal resources, the complexity of ores and the fineness of grind required to liberate minerals have become serious problems. When ores are complex, several valuable minerals may interact with each other and reactions may become more complicated compared with an ore containing only one valuable mineral. Therefore, more processing steps may be required than for a simple ore. When the valuable minerals exist as fine grains, it is difficult to liberate them and more grinding time is required. Furthermore, the probability of collision of fine particles with bubbles in the flotation process declines and it takes much time to recover them. Flotation is one of the most applied methods to separate valuable minerals from unwanted ones using the difference of hydrophobicity (or hydrophilicity). In the flotation method, the air is fed to a cell filled with the pulp of the mineral of interest and agitation is implemented to introduce air and generate bubbles. The hydrophobic particles attach themselves to the bubbles and float along with the bubbles while the hydrophilic particles remain in the pulp. Copper sulfide minerals such as chalcocite (Cu2S), bornite (Cu5FeS4), chalcopyrite (CuFeS2) are widely known abundant copper resources. Generally, flotation is used to recover and concentrate these minerals. Copper sulfide minerals usually have high floatability. However when their surfaces are oxidized, their floatability becomes lower. When the sulfide surfaces are oxidized, activators are added before flotation to modify the surface property of the Copper sulfide minerals so that they can be floated. Sodium hydrosulfide, NaHS, is known as one of the activators. Zhao (2018) reported that NaHS is often used as a sulfurizer for oxidized sulfide minerals (Becker (2014), Clark (2000), Newell (2006), and Newell (2007)). In earlier work, the authors performed flotation tests on a sample of Chilean copper ore which contained chalcocite, bornite, and chalcopyrite using a Denver-type flotation apparatus. The sample was ground to P80 70 µm with a rod mill and ball mill. In these tests, the following conditions were used: natural pH (about pH 8.5), flotation time of 45 min, 60 g/t AP3477 (sodium diisobutyl dithiophosphate) as collector, and MIBC (methyl isobutyl carbinol) at appropriate dosage as frother. NaHS was applied at the dosage of 0, 67, and 120 g/t, respectively at the conditioning. The concentrates were collected at 6, 18, 30, and 45 min. The weights of the concentrates and tailing were measured and they were assayed for copper by ICP-AES (Optima 5300 DV, PerkinElmer Inc.). The flotation recoveries of the copper minerals were calculated from the results of MLA (mineral liberation analyser) (MLA 650, FEI) measurements.

Jan 1, 2019

By K. A. Natarajan, M. N. Chandraprabha

Selective separation of minerals from complex sulphide ores is a challenging task and it is often difficult to get commercially acceptable individual concentrates by conventional selective flotation using inorganic collector reagents. Microbially-induced mineral beneficiation has proved to be more effective, economically viable and an environmentally benign process for the effective separation of various minerals. Applications of microbially-induced mineral beneficiation are demonstrated in this paper with respect to beneficiation of complex multimetal sulfides. The role of adapted microorganisms and bioreagents in the beneficiation of complex sulphide minerals are also illustrated.

Jan 1, 2009

By J. Bouchard, M. Levesque, D. Georges-Filteau, P. Radziszewski, G. LeBlanc

"Grinding mills are infamous for their extremely low energy efficiency. This paper reports the results of an investigation that characterized energy outputs in industrial grinding mill circuits. It identifies and discusses the potential for recovering energy from grinding circuits. Agnico-Eagle Goldex Division, Mine Canadian Malartic, and New Gold New Afton Mine participated in the study by providing operating data for three semi-autogenous grinding mills and four ball mills. Results showed that on average, 79% of the supplied electrical energy was converted to heat absorbed by the slurry, 8% was lost through the drive system, and approximately 2% was transmitted to the ambient air. Only 9% of the input energy was actually used for grinding. The remaining 91%—wasted as heat—could potentially be recovered using suitable technologies or integrated energy management systems. This topic remains to be further investigated. ¦ KEYWORDS Comminution processes, Energy recovery potential, Grinding mills RÉSUMÉ Les broyeurs sont tristement célèbres pour leur rendement énergétique médiocre. Cet article présente les résultats d’une étude qui caractérise les rendements énergétiques des circuits industriels de broyage et examine les possibilités de récupération d’énergie dans les circuits de broyage. La mine Goldex d’Agnico Eagle, Mine Canadian Malartic et la mine New Afton de New Gold ont participé à l’étude en fournissant des données de fonctionnement pour trois broyeurs semi-autogènes et quatre broyeurs à boulets. Les résultats montrent qu’en moyenne 79 % de l’énergie électrique fournie sont convertis en chaleur absorbée par la pulpe, 8 % sont perdus dans le système d’entraînement et environ 2 % sont dispersés dans l’air ambiant. Seuls 9 % de l’énergie primaire sont, de fait, utilisés pour le broyage ; les 91 % restants (perdus sous forme de chaleur) peuvent potentiellement être récupérés à l’aide de technologies adaptées ou intégrées dans des systèmes de gestion de l’énergie. Cette question demeure toutefois ouverte. ¦ MOTS CLÉS broyeurs, potentiel de récupération de l’énergie, procédés de comminution INTRODUCTION Grinding is largely recognized as a very inefficient process; energy efficiency estimates range from < 1 to 2% (Fuerstenau & Abouzeid, 2002; Tromans & Meech, 2002, 2004) when comparing the input energy to that required for generating new mineral surfaces. Criticizing an “ill definition of the reference for the output energy,” Fuerstenau and Abouzeid (2002) proposed a “more meaningful baseline” would be “the energy for producing new surface area by the ¬mens.” Based on this reference, they concluded that “the ball mill is reasonably efficient energetically,” exhibiting an efficiency of approximately 15% for quartz."

Jan 1, 2019

By J. E. Dutrizac, Alba Sunyer

The factors affecting the precipitation of arsenic-free alunite (KAl3(SO4)2(OH)6) were investigated in a series of laboratory experiments. Although the amount of alunite precipitated increased with increasing retention time, temperature, solution pH and the concentrations of Al(SO4)1.5 or K2SO4, the composition of the products remained nearly constant. The preferred conditions identified for the precipitation of arsenic-free alunite were then used to assess the behaviour As(III) and As(V) during alunite precipitation at 98°C. Increasing additions of As(III), as NaAsO2 or As2O3, resulted in a slight increase in the amount of precipitate formed at pH 2.80. However, X-ray diffraction analysis showed all the precipitates to be alunite, and <0.2% As(III) was detected in the products. In contrast, increasing additions of As(V), as KH2AsO4 or As2O5, resulted in significant increases in the amount of precipitate formed at pH 2.80 or 3.00. Furthermore, the arsenate (AsO43-) contents of the precipitates increased up to 15%, and the sulphate contents decreased, as the As(V) concentration of the synthesis solution increased from 0 to 9 g/L. X-ray diffraction analysis of the products detected only alunite, but there was a progressive expansion of the alunite cell with increasing arsenate content. The implication is that arsenate substitutes for sulphate in the alunite structure. Preliminary observations on the environmental stability of the arsenate-bearing alunite using the TCLP protocol gave solubilities <0.4 mg/L from a precipitate containing 8.5% AsO4 and 7.8 mg/L from a product containing 19.5% AsO4. Thus, it appears that alunites containing less than -10% AsO4 would be an acceptable vehicle for the disposal of arsenic from hydrometallurgical processing solutions.

Jan 1, 2011

Of the many organic impurities present in Bayer liquor, sodium oxalate is known to have one of the most detrimental effects on the Bayer process. Because of its limited solubility, it will co-precipitate with gibbsite during the precipitation stage which results in many operational challenges for the refinery. Despite the importance of this phenomenon, the interaction mechanism between gibbsite and sodium oxalate is not well understood. In this study, the growth of sodium oxalate on three main morphologies (random agglomerates, prims and hexagons) of water-washed and caustic-washed gibbsite was observed under synthetic Bayer conditions using in situ optical microscopy. After a short induction period, oxalate started to nucleate on gibbsite crystals, and grew with a needle-shaped morphology which eventually developed into oxalate bundles. In addition, the results indicated that caustic washing was able to partly decompose gibbsite crystals and thus make the gibbsite surface rougher, which provides more potential sites for oxalate nucleation and growth. The growth rate of oxalate crystals on the basal (001) face of water-washed gibbsite was 1.33 µm/min determined by the time-lapse imaging of in situ optical microscope.

Jan 1, 2014

By K. C. Corin, Z. G. Song, J. G. Wiese

In the present investigation flotation was used as a diagnostic to understand the effects of changes to the media during the grinding stage. The observations from flotation for different media are discussed in terms of particle size distribution, water recovery, solid recovery and valuable mineral recovery. The chemical parameters; pH, redox potential (Eh) and dissolved oxygen (DO) levels were measured. A Base Metal Sulphide (BMS) ore was ground under media of different shapes and compositions to determine the effect of different rod/ball material on the flotation performance of the ore. For a given grind (D80 = 75 µm), media shape had no effect on flotation performance of a BMS ore. Different grinding media had significant effect on slurry chemical properties and flotation performance. Mild steel rods (RMMS) produced the highest solids recovery, nickel and pyrrhotite (Po) recovery, with the highest ethylenediaminetetraacetic acid (EDTA) extractable iron and the lowest DO level. Chrome steel balls and stainless steel rods produced the lowest metal recovery, EDTA extractable iron and the highest DO level. A complementary study was conducted to investigate the effect of using different grinding media compositions, viz, ceramic, forged steel, 15% chrome steel, stainless steel and a mixture of stainless steel and 15% chrome steel (50:50) balls were investigated using a Platinum Group Mineral (PGM), UG2 ore. Grinding products of five different media produced the same solids and water recovery, but the grades and recoveries of Platinum Group Elements (PGE) and chromite were different. Grinding products of ceramic media showed the best flotation performance, with the highest PGE recovery and the lowest Cr2O3 recovery. While grinding products of stainless steel balls (SS) produced the lowest PGE recovery and highest Cr2O3 grade and recovery in the concentrates.

Jan 1, 2016

By F. H. Samuel, H. Tahiri, S. Valtierra, H. W. Doty, A. M. Samuel

L&apos;affinage des grains dans les alliages d&apos;aluminium consiste à augmenter le nombre de sites de cristallisation de la phase a-Al afin d&apos;obtenir une structure fine. Les alliages mères de type Al-Ti-B sont largement utilisés comme raffineurs des grains. Cette étude a pour but d&apos;établir des mécanismes convenables d&apos;affinage des grains dans l&apos;alliage A356 en utilisant cinq alliages mères et deux températures de coulée (750°C et 950°C). Les résultats montrent que la phase a-Al prend une forme selon l&apos;alliage mère ajoute; les échantillons coules a haute température montrent une taille de grain plus grosse; les températures de germination et de croissance augmentent avec I&apos; augmentation du Ti ou du B et la taille des grains diminue. L&apos;alliage mère Al-4%B montre une puissance remarquable en comparaison d&apos;autres alliages mères. Pour cet alliage mère, le titane résiduel dans l&apos;alliage A356 réagit avec le bore pour former TiB2 qui, par la suite, agit comme un germe actif pour la phase a-Al.

Jan 1, 2006

By B. Fang

Electrochemical behavior of an X-80 pipeline steel, including frequency-sweep electrochemical-impedance spectroscopy (EIS), time-sweep EIS at a constant frequency and open-circuit potential (OCP) monitor, was investigated using four-point bending specimens subjected to a stress-corrosion cracking (SCC) test in a near-neutral pH environment, The capacitive loop became smaller with test duration, revealing an increase in the corrosion rate, The resistance obtained in the constant-frequency EIS test showed two regions, of which the region with a remarkable decrease in resistance transformed into a region of slow decrease, whereas the capacitance increased with test time indicating that iron dissolution was fast at first, and then a corrosion product or film formed and covered the surface, leading to the pitting formation.

Jan 1, 2005

By L. Li

Iron removal is a common procedure in hydrometallurgy of non-ferrous metallic ores. Chemical precipitation and solvent extraction are currently the main methods employed for separation of iron from copper leach solution. However, chemical precipitation methods have the problem of producing large amounts of iron precipitates, and/or requiring high temperature and high pressure conditions for precipitation. The precipitates are difficult to separate from the solution. Emulsification is a general problem for solvent extraction, which causes loss of extractants and contamination of the electrolyte. A common problem for solvent extraction and chelating ion exchange processes is the difficult iron stripping process. Therefore, finding an efficient and environmentally friendly method for iron removal is of great significance. In this paper, new processes of using ion exchange resins to remove iron from copper leach solution have been investigated. Salicylic acid, amino carboxylic acid, amino phosphonic acid and hydroxy-oxime resins were employed to adsorb iron from a simulated copper leach solution containing 40 g/L of Cu2+ and 36 g/L of Fe3+. It was found that a hydroxy-oxime resin, named Z-Fe, has excellent adsorption selectivity on Fe3+. Desorption behavior of the resin was studied by two step elution using dilute H2SO4 and oxalic acid solution, respectively. After optimizing the adsorption-elution processes, the extent of removal of iron from the simulated copper leach solution using resin Z-Fe was 90%, while copper recovery could reach 100% in closed circuit processing.

Jan 1, 2016

By Therese Schneck

The presence of xenon isotopes from in-situ spontaneous fission of short-lived Pu244 has been confirmed in Hadean detrital zircons from Western Australia. Hadean and meteoritic zircons can retain secondary overgrowths developed after primary cristalization at 3.97-3.94 Gyr. On the moon, the metal grain in sample 66095,78 is mantled by troilite, schreibersite and cohenite. High chlorine content FeCl2 is deposited around metallic FeNi. The magnitude of Pollonium-210 to Radon-222 on the Aristarchus plateau spectrum indicates a past greater activity. The Earth Moon system from Nb/Ta systematics is consistent with a Moon iron core delayed to 3,9 Gyr.

Aug 1, 2010