Search Documents

By Dale Scott

"The Aggregate Resources Inventory Program was initiated 10 produce reports which assess the aggregate resources of municipalities designated under the Pits and Quarries Control ACI, 1971.Each report consists of three copies accompanied by a text. The text describes the local mineral aggregate resources, extractive activity and characteristics of the ""Selected Deposits"". The first map shows the known sand and gravel resources and their quality. The second map indicates selected sand and gravel resources of primary, secondary and tertiary significance. The third map indicates both bedrock resources and bedrock areas suitable f or extraction. These maps and the text are prepared in a formal suited for use by planning personnel.Recently, the Aggregate Resources Inventory Program has undergone evolutionary changes. New sources of data are being utilized in the inventory reports; in particular, detailed field assessment by inspecting, sampling, drilling and backhoe pitting. Liaison and joint assessment with district and regional Mineral Resources staff of the Ministry of Natural Resources, and personnel of the Ministry of Transportation and Communications, are key components of the Program.Twenty-two reports were available to the public as of December 1980, with a further thirty-six awaiting publication. Our present production rate is 3.5 reports per month. The reports appear to be well accepted by the municipalities and have proven effective in conserving prime aggregate resource areas.IntroductionThe urbanization of Southern Ontario has resulted in a major increase in the production of industrial minerals, such as sand, gravel, clay, shale, gypsum and stone, for use as cru shed aggregate, building stone, lime and cement.Although mineral aggregate deposits are plentiful in Southern Ontario, they are fixed-location, non-renewable resources. The potential for extractive development is usually greatest in urban fringe areas where land-use competition is extreme. Comprehensive planning and resource management strategies are required to make the best use of available resources, especially in those areas experiencing rapid development. Such strategies must be based on a sound knowledge of the total mineral aggregate resource base at both local and regional levels."

Jan 1, 1982

By Dale Scott

"The Aggregate Resources Inventory Program was initiated 10 produce reports which assess the aggregate resources of municipalities designated under the Pits and Quarries Control ACI, 1971.Each report consists of three copies accompanied by a text. The text describes the local mineral aggregate resources, extractive activity and characteristics of the ""Selected Deposits"". The first map shows the known sand and gravel resources and their quality. The second map indicates selected sand and gravel resources of primary, secondary and tertiary significance. The third map indicates both bedrock resources and bedrock areas suitable f or extraction. These maps and the text are prepared in a formal suited for use by planning personnel.Recently, the Aggregate Resources Inventory Program has undergone evolutionary changes. New sources of data are being utilized in the inventory reports; in particular, detailed field assessment by inspecting, sampling, drilling and backhoe pitting. Liaison and joint assessment with district and regional Mineral Resources staff of the Ministry of Natural Resources, and personnel of the Ministry of Transportation and Communications, are key components of the Program.Twenty-two reports were available to the public as of December 1980, with a further thirty-six awaiting publication. Our present production rate is 3.5 reports per month. The reports appear to be well accepted by the municipalities and have proven effective in conserving prime aggregate resource areas.IntroductionThe urbanization of Southern Ontario has resulted in a major increase in the production of industrial minerals, such as sand, gravel, clay, shale, gypsum and stone, for use as cru shed aggregate, building stone, lime and cement.Although mineral aggregate deposits are plentiful in Southern Ontario, they are fixed-location, non-renewable resources. The potential for extractive development is usually greatest in urban fringe areas where land-use competition is extreme. Comprehensive planning and resource management strategies are required to make the best use of available resources, especially in those areas experiencing rapid development. Such strategies must be based on a sound knowledge of the total mineral aggregate resource base at both local and regional levels."

Jan 1, 1982

By C. H. B. Leitch

"The Bralorne-Pioneer deposit produced more gold than any other deposit in British Columbia over its 70 years of operation (130 kg or 4 million oz of Au, from 7 million tonnes of 18 glt ore). Mineralization is related to a suite of late Cretaceous albitite dykes of 85 to 90 Ma age. It thus occurred long after and is genetically unrelated to the Early Permian (275 Ma) Bralorne diorite and soda granite.The major veins strike about 110 degrees and dip north at 70 degrees, with slickensides plunging 45 degrees east that indicate last movement was reverse. Major ore shoots in the veins occupy somewhat less than 20% of the vein and plunge steeply west, roughly perpendicular to the slickensides. The structures that contain the veins probably formed at around 95 to 90 Ma during a strike-slip episode with easterly directed maximum compression.Disseminated pyrite, pyrrhotite, and minor chalcopyrite occur within envelopes up to several metres from the veins. Arsenopyrite is confined to vein selvages. Local sphalerite and galena appear to correlate with gold-rich portions of the veins. Traces of tetrahedrite and stibnite have been observed but tellurides have not. Gold is found principally as thin smeared flakes of the native metal in the black sulphidic septae of the strongly ribboned veins. Hydrothermal alteration envelopes around the veins grade outwards from intensely foliated quartz - ankerite - sercite (±fuchsite) to less sheared calcite - chlorite - albite to unsheared epidote -calcite.Open-space vein filling textures found in the deep (mesothermal) environment at Bralorne can be explained by a fault- valve model. High-angle reverse faults may have acted as fluid-pressure activated valves on geopressured reservoirs, causing large cyclic fluctuations in fluid pressure that promoted mineral deposition in an episodic fashion . The faults that were mineralized were reactivated sub-vertical former strike slip faults, oriented at a high angle to the northeast-directed stress in a compressive regime."

Jan 1, 1990

By N. Thompson

The Right Hon. Viscount Long, late Secretary of State for the Colonies, in his inaugural address to the Empire Mining and Metallurgical Congress in London last June said: "I am more and more? convinced by every day experience that the development and strengthening of the Empire must depend upon individual effort and action, and that it is useless to look to Governments for assistance." I am inclined to agree with Viscount Long, to this extent, that the initiative must come from individual effort, but Government assistance is necessary to put the results of that effort and action into effect. It is perhaps fitting at a gathering of this kind to remind ourselves of the part the mining industry has played, not only in the development of the British Empire but in the world at large, in the promotion of modern civilization. We do know that all human progress has been coincident with the early discoveries in the recovery and treatment of metals and, as the centuries have passed, the human race has become more and more dependent on these sciences as factors of all progress, and no nation has ever become powerful and prosperous that has lacked adequate mineral supplies, or having these, has allowed them to be exploited by other nations.

Jan 1, 1925

By Ken Wood, Luc Duval

"The development and operation of the milling circuits treating the different Selbaie orebodies are discussed in this paper. The project is reviewed from metallurgical evaluation through construction to present operating status. The current flowsheets are described, with discussion of some unusual features.IntroductionThe Selbaie concentrator commenced initial production in August 1981, treating underground B zone copper ore in a single 1500 t/d circuit. Throughput was increased to 1650 t/d in 1985. The mill was expanded in 1986 to treat ore from the A-I zone open pit; an independent circuit was added to selectively treat 5000 t/d of copper-zinc ore. Current total mill throughput through both circuits averages 7200 t/d with the production of approximately 270 t/d of copper concentrate and 230 t/d of zinc concentrate.This paper describes the stages involved in bringing the project from initial laboratory testing to its current status as one of the most important producers of silver, copper and zinc in Quebec and a major employer in the region."

Jan 1, 1990

By U. Erb, L. Monaco

"Electrodeposited nanomaterials are increasingly implemented in advanced industrial applications in the aerospace, automotive, defence, electronic and energy sectors due to their outstanding physical, chemical and mechanical properties, including increased strength and wear resistance, and superb magnetic properties. As with the development of any class of new materials, the corrosion behaviour of these electrodeposits requires considerable attention. This presentation reviews major developments in the understanding of the corrosion behaviour of nanocrystalline metals, alloys and metal-matrix composites over the last 20 years, with emphasis on how their intrinsically high density of intercrystalline defects does not compromise their corrosion resistance as initially expected.INTRODUCTIONOver the past 20 years there have been considerable advances in the understanding of the corrosion behaviour of nanocrystalline metals, alloys and metal-matrix composites. In this paper, the corrosion properties of nanocrystalline nickel, cobalt, zinc, and copper and some of their alloys are reviewed with emphasis on how a reduction in grain size affects their corrosion behaviour in different environments.It is possible to synthesize nanocrystalline material with microstructural refinement down to the range of 1 to 100 nm using a large number of processing methods. There are five basic synthesis methods that can be used to classify the different techniques: vapor-phase processing, liquid-phase processing, solid-phase processing, chemical synthesis, and electrochemical synthesis. Depending on the synthesis method, different microstructures (equiaxed, textured), shapes, and forms (films, particles, bulk material) may be produced. In addition, other factors may be introduced (eg. residual porosity or amorphous phases), aside from microstructural refinement, which can contribute to the observed properties (Erb, 2010). In order to interpret and categorize the resulting microstructures, a dimensional structure modulation scheme was introduced by Siegel (1996) in which zero-dimensional nanomaterials refer to individual particles, clusters, etc. One-dimensionality results from a layered (less than 100 nm thick) structure. Two-dimensional nanomaterials are thin, layered structures containing grains (less than 100 nm) within each layer. Finally, three-dimensional nanomaterials are bulk structures with an average grain size less than 100 nm."

Jan 1, 2012

Agenda ? Where?s Victor ? What work was done to get approval to spend $982m ? a brief history ? Some project facts ? The triple bottom-line accomplishments to date ? Construction A Brief History of Victor ? 1960?s ? first sampling in area ? 1980?s ? stream samples and Victor kimberlite discovered ? 1990?s ? test / bulk samples ? 1999 / 2000 ? large bulk samples ? 2000 / 2003 ? technical evaluation through to Feasibility Study, permitting process

May 1, 2006

By W. E. Coates

The social ecology of surface mining in urban areas is illustrated by a case study of a recent application for the opening of a new gravel pit in the city of Guelph, including the design of a progressive extraction-rehabilitation sequence for the property, investigation of the ecological impact of the proposed operation, history of the application procedure for a zoning change and the relationship of the operating plan to provincial legislation controlling surface mining.

Jan 1, 1972

By M. Epiney, A. Ghahreman, R. Kim1and

"In the presence of sulfidic refractory ores, increasing the dissolved oxygen (DO) concentration can positively affect the gold leaching rate. To identify the role of DO in gold cyanidation, electrochemical behavior was studied in the presence of 3 different ores. Sample 1 was a low sulfide pyrite ore, contained 5.14% pyrite, 0.19% galena and 3.09% S. Sample 2 was a pyriticore as well, contained more sulfide as 8.35% S, and 12.4% of pyrite. Sample 3 was a tailing of silicate gold ore, still containing75 g/tAu, 0.13% Pb and 0.18% S. Gold cyanidation kinetics were studied by cyclic voltammetry (CV) and chronoamperometry tests. With sample 1, the gold oxidation peak current density from CV curve was increased to 1.38mA/cm2under oxygen injection, while it was only 0.66 mA/cm2with air injection. From chronoamperometry test, the reaction rate was also faster under oxygen injection. Sample 2 showed similar behavior with sample 1, but the gold oxidation peaks higher than sample 1, i.e. 1.75 and 2.27 mA/cm2, under air and oxygen injection, respectively. However, it seemed that the gold oxidation was impeded by sulfide ions for a longer period. In the presence of sample 3, the gold oxidation peak was the highest among three ores –2.75mA/cm2under oxygen injection, because of its lowest sulfide content. However, from chronoamperometry test, it was also shown that the gold oxidation was impeded because of a significant amount of Pb in the ore sample.INTRODUCTIONIt is well known that gold is leached under oxidative condition (Marsden &House, 2006). Through the most representative and oldest gold leaching technique, cyanidation, more than 90% of gold can be selectively leached from an ore. According to Elsner’s equation, gold is leached in cyanide solution by forming cyanide complex [Au (CN)2–], and oxygen is consumed as an oxidant(Eq. 1)."

Jan 1, 2017

By G. Gabra

"A process of leaching niobium oxide from pyrochlore concentrate using hydrofluoric acid is described. Variables such as acid concentration, temperature, reaction time, solid/acid ratio, agitation speed and particle size are correlated to the recovery of niobium oxide.The relatively low activation energy (1,86 Kcal/mole) and the dependence of reaction rate on agitation suggest that the process is diffusion controlled. The optimum conditions for extracting niobium oxide from the leach solution, using either methyl isobutyl ketone or tributyl phosphate have been determined.IntroductionMost of the commercial production of niobium and tantalum has been derived from the treatment of columbite - tantalite minerals.In recent years (1960) , pyrochlore mineral has been found to be an alternate source of niobium . This mineral varies widely in composition and contains in addition to the main elements of calcium , sodium and niobium, some tantalum, fluorine, rare earth elements, titanium, alkali an d alkaline earth elements.It is well known that the province of Quebec possesses several pyrochlore niobium deposits totalling approximately 151 million ton s at an average 0.45% niobium oxide(1). One of the deposits, the St-Honor carbonatite, was brought into production by Niobec Inc. in 1976. Flotation o f this material produces a concentrate of about 60% Nb205(2).In view of an expanding niobium market in recent years and the presence of large niobium deposits in the province, a research and development program was initiated at the Centre de Recherches Miner ales to evaluate known processes for the separation of niobium and tantalum from each other as well as their purification . Some work has also been undertaken at the CRM to develop an improved extraction process. T his work will be the subject of further communication s."

Jan 1, 1985

By John J. Barakso

A summary of geochemical dispersion processes is presented. Secondary and tertiary dispersion of uranium was examined at several uranium prospects in British Columbia. The vertical migration of uranium from bedrock (primary dispersion) through overburden into the various soil horizons, and into snow and plants, was studied, and relationships were sought to explain the dispersion patterns in the secondary and tertiary environments. Soil developments were examined to obtain information on factors affecting the dispersion of uranium in soil profiles and tertiary substances; samples were analyzed for a number of elements. Biogeochemical data indicate that plant geochemistry is a possible exploration aid in areas of heavy overburden owing to the high selectivity of certain plants for specific elements. Some new data on the geochemistry of snow are discussed as a matter of research interest in the tertiary dispersion of uranium. Analytical techniques and problems are discussed, particularly extraction techniques, which must be carefully chosen to give reliable information on uranium dispersion.

Jan 1, 1979

By Jarrett. K. M.

Nobody has, as yet, made a perfect machine. Therefore, when a machine is operating and functioning as it is designed to do, there is always some vibration present. This is easily and simply measurable with present-day equipment and any increase in the amount of vibration will indicate a potential failure. When an increase is noted, vibration analysis can pinpoint the cause of the potential failure and remedial action can be taken before an unscheduled shutdown is necessary or a breakdown occurs.

Jan 1, 1972

By H. Sato, Y. Sato, T. Ooishi, K. Sakamoto

"Sumitomo Metal Mining Co., Ltd.(SMM)'s Niihama Nickel Refinery(NNR) produces high quality Nickel cathode, Cobaltcathode and other by-products using hydrometallurgical refining process called “MCLE”(Matte Chlorine Leach and Electro-Winning). In 2005,NNR started to use nickel and cobalt mixed sulfide (MS) produced by one of the SMM’s subsidiaries Coral Bay Nickel Corporation(CBNC)’s HPAL plant in Philippines, although its main and the only raw material until then was nickel matte. With start-up of the second HPAL plant at Taganito in 2013, NNR expanded its production capacity of nickel cathode from 41,000 to 65,000 tpa and finally achieved its target in 2015 by producing 65,980 tpa. SMM developed the technologies to improve poor reactivity of MS and installed new facilities to cope with increased Cobalt and Sulfur production at that time. This paper describes the technical approach to increase MS treatment with high efficiency.INTRODUCTIONThe Sumitomo Metal Mining Co., Ltd.(SMM)Niihama Nickel Refinery(NNR) produces Nickel cathode, Cobalt cathode and other by-products using Matte Chlorine Leach and Electro-Winning (MCLE) process technology. SMM uses nickel matte and nickel & cobalt mixed sulfide (MS) as raw materials for the MCLE process. Table 1 shows typical composition of these raw materials. Nickel matte had been only raw material until 2005, and with start-up of Coral Bay Nickel Corporation (CBNC) operation in the Republic of the Philippines, MS became major part of it. In 2009, when CBNC doubled its production capacity, NNR also expanded its plant capacity of electrolytic nickel from 36ktpa to 41ktpa, keeping an eye on the possibility of 65ktpa with oncoming SMM’s second HPAL in Philippines. Poor reactivity of MS was the prime concern at that time because our intention was to increase production with MS. Nickel extraction rate deteriorated with increasing usage ratio of MS in raw materials. To keep high nickel extraction rate under high ratio of MS, NNR developed a new leaching technology. Another concern arising from treatment of MS was Cobalt and Sulfur contents that are much more than those of nickel matte as shown in Table 1.NNR introduced new technology of solvent extraction process as to Co/Ni separation process in order to keep cost competitiveness instead of the conventional cobalt oxidation–neutralizing method. As to sulfur products, new sulfur productive facility was installed to improve the exposure to sulfur dust and the hot working conditions for workers. As a result of process development and installation of new facilities against the problem with MSusage,65 ktpa production was achieved in 2015."

Jan 1, 2017

By S. Hosseinpour

Chromate conversion coatings (CCCs) are usually applied to these alloys to enhance their resistance to localized corrosion and to improve paint adhesion. The special properties of these coatings such as their low electrical contact resistance (ECR) make them suitable for satellites. This study is aimed to develop advanced CCCs with the proper appearance, morphologies and surface roughness and to evaluate their role on the ECR and thermo physical properties on hardened aluminium alloy of Alclad-7075-T6. Coating characterization was performed by means of scanning electron microscope (SEM) and atomic force microscope (AFM). ECR of coatings were measured by special laboratory designed instrument and a and c were measured by Emissometer and Reflectometer respectively. In addition, corrosion performance of the CCC-coated alloys was determined by 168 hr exposing to salt-spray testing in accordance with ASTM-B117. The results of accomplished experiments on the developed CCCs in this study have been agreeable concerning available acceptability criteria for satellite surfaces.

Jan 1, 2007

By Euler De Souza, J. Daniel Stinnette, Julian Varaschin

"This paper outlines some of the factors that affect the airflow required for the ventilation of modern diesel-powered equipment and of electric equipment and examines how they can be applied in determining reasonable ventilation rates for Tier IV compliant diesel equipment and for electric equipment operating in mining environments. Airflow calculations for modern diesel-powered equipment and for electric equipment are more complex and must be based on a combination of factors that are unique to each mine. Methodologies for ventilation rate determinations for each case are proposed in this paper.INTRODUCTIONTraditionally, airflow requirements for production and support equipment operating in underground mines have been determined by multiplying the vehicle power by a ventilation rate that was either mandated by regulations or determined empirically from known quantities. However, in light of the drastic reductions to diesel equipment emissions mandated by the US EPA Tier IV and EURO Stage 4 regulations, there is still a great deal of uncertainty in the underground mining industry among those responsible for the ventilation of planned new mines or the expansion of current mines. The question remains, what ventilation rates should the ventilation system designer apply for modern diesel equipment?Also, given the ongoing development of grid/battery-electric equipment and active construction of fully electric mines, it has become critical to determine adequate airflow rates per brake kilowatt of electric engine power. One of the most important criteria for determining ventilation rates for electric equipment is the amount of heat they generate, as this is the most significant emission produced by electric equipment (which do not produce exhaust gases or particulates). Therefore, ventilation rates required to dissipate heat from electric equipment must be suitably determined for all electric vehicle fleets operating in underground mines."

Jan 1, 2019

By D. Furrer, M. Dallaire

The arrival of Image analysis in the last 20 years has changed the world of quantitative metallography. Many standard measurement techniques which were previously manual can now be done with fully automated systems. This reduces subjectivity and operator fatigue and therefore enhances the quality of the statistical results. In many laboratories, Titanium Alloy microstructures continue to be evaluated by traditional methods, where quality of results is subject to operator fatigue and level of experience. Advances in Camera technology have tremendously improved image acquisition. One can often see clearly at 500x what can not be observed at 1000x, allowing for a larger area to be analyzed, without the inconveniences associated with very high magnification objectives. Powerful and versatile Image analysis software combined with a high precision motorized stage gives access to a multitude of applications, which were extremely challenging or impossible until now. Image Analysis tools such as Multilayer Grab, which reconstructs an uneven image into one plane of focus (ex. Observation at high magnification of texture resulting from etching) and Mosaic which builds an image from a number of fields of view (ex. Reconstruction of very large grains at low magnifications) expand even further the power and flexibility of IA systems. This presentation will describe how automated methods are applied to the point count method and grain size measurement. We will show how cameras and software work together to permit quantitative measurements of primary alpha and prior beta microstructures, as well as lamellar alpha plate thickness in titanium alloys.Automated and semi automated quantitative measurements of various Titanium microstrures have been assessed, using the Clemex Vision PE. Examples of the methods and steps used are presented.

Jan 1, 2006

By Xiu-Xiang Tao

This study investigated bio-liquefaction of lignite and its model compounds of thymol, bezioc acid and quinoline by a fungus, Hypocrea lixii AH. It analyzed, during bio-liquefaction, enzyme activity of oxidase, LiP, Lac, MnP and polyphenol oxidase, and degradation products by UV-Vis, FTIR, 13C NMR and GC-MS. The results showed that the bio-liquefaction percentage (by mass) of lignite was up to 44.86 %. The bio-liquefaction products of lignite were mainly aniline, amide, ether, carboxylic acid ketone and ester. The aromatic ring number was 1-3 with an aromatic carbon ratio of 0.328, which indicated rings opening, bonds breaking and oxidation reaction. By considering with the enzyme activity analysis results, it showed that LiP and Lac catalyzed reactions to open aromatic cycles and to break bonds; esterase to break ester bond; and peroxidase in oxidation reaction.

Aug 1, 2013

By Janice Zinck, Maziar E. Sauber

"To counter the recent uncertainty in the rare earths market, diversify the supply source, and help meet the future demand in this sector Canada initiated development of several new rare earth deposits. In the past few years, a number of various studies on rare earths plant design have taken place mainly covering process development, process selection, and flowsheet design. The purpose of this paper is to provide an overview of known domestic and potential resources and reserves of rare earths and their status quo with a focus on the metallurgical processes using the information available in the public domain. Plant designs currently under consideration in Canada are reviewed and evaluated. An outline of the areas of opportunity for selective innovation and technology development in the rare earths flowsheet development and the associated risks and rewards is provided.INTRODUCTIONThe rare earth elements (REE) have a very small annual market, but they are categorized as very strategic metals vital to global economic growth due to their indispensability to the development of modern defence system, green technologies and electronic applications. The International Union of Applied and Pure Chemistry (IUPAC) defines the REE as the 15 elements on the lanthanide series on periodic table of elements, plus yttrium and scandium. REE are classified as light rare earth elements (LREE; La to Gd), and heavy rare earth elements (HREE; Tb to Lu). Physical properties and chemical reactivity of yttrium is similar to those of HREE, thus it is categorized as such. Properties of scandium are not similar enough to classify it as either a LREE or HREE (Weng et al., 2015; Sappin & Beaudoin, 2015). However, the mining industry does not always abide to this definitive classification of the split between LREE and HREE. Therefore, in a comparative study of projects, there is a need to pay attention to how the elements are classified."

Jan 1, 2016

By O. Worku, J. H. Masliyah, Z. A. Zhou

ABSTRACT The viscosity of concentrated kaolinite or illite clay in aqueous suspensions was measured in the presence and absence of a small amount of montmorillonite (<1 wt%). To avoid solids settling and to increase the sensitivity of the suspension viscosity measurements, solids concentrations higher than 38 wt% were used. The pH of the suspensions and the concentration of calcium and bicarbonate ions were found to significantly impact the viscosity of the clay suspensions. The results showed a significant increase in the viscosity of kaolinite suspensions with the addition of as low as 0.25 wt% of montmorillonite on a solids weight basis. In addition to illustrating the role of water chemistry in modifying slurry rheological properties, our study demonstrated that viscosity measurement could be a simple, yet sensitive technique for determining the content of smectite clays, such as montmorillonite, in a complex mix of various types of clay.

Jan 1, 2012

By T. Feldmann, G. P. Demopoulos

The adsorption of gold complexes on inorganic metal oxides has been mainly discussed in geochemical literature, but it is also of interest to the hydrometallurgical industry. This is so because it could be responsible for valuable metal losses or because it could potentially serve as alternative adsorbent material to activated carbon in certain cases such as from hot and acidic process slurries. This paper constitutes an early investigation into this subject by focusing on the effectiveness of FeOOH, Fe3O4 and Al2O3 as sorbent materials. All tests were done in a batch stirred-tank reactor under atmospheric conditions with synthetic gold(III)-chloride solutions at 23°C and 80°C, in the pH range of 1.6 to 9.0. Detailed kinetic tests were performed at different pH values (3 and 6) on FeOOH and Fe3O4 with solutions having gold concentrations from 5 mg/L to 130 mg/L. The adsorption of gold was found to be best both in terms of kinetics and loading characteristics at 80°C and pH=6. This was explained by a change in Au(III)-Cl speciation from a gold(III)-chloride complex to a gold(III)-chloride-hydroxy complex. By far, magnetite (reagent grade chemical) yielded the best gold adsorption characteristics making it an interesting sorbent material for further development considering that it can be advantageously recovered from slurry streams via magnetic separation. On the other hand, the tendency of gold(III)-chloro complexes to adsorb on metal (hydro) oxides needs to be taken into account to minimize undesirable metal losses in chloride-containing leaching media.

Jan 1, 2015