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By D. K. Bose, R. H. Rakhasia, V. D. Shah, J. C. Sehra

A series of experiments was conducted to determine the effects of roasting temperature, soaking period and quantity of soda ash added. At a laboratory scale, under optimum conditions of roasting at 873 K for 2 700 s with soda ash 10 wt% in excess of stoichiometric, molybdenum recovery was 99%. The investigations indicate the technical feasibility of producing high-purity MoO3 by combining the roasting process with carbon adsorption/desorption. The process uses low-cost chemicals, can be scaled up readily and is free of the SO2 pollution generated by conventional roasting, as the sulphur content of the concentrate is converted to sodium sulphate

Jun 18, 1905

By John W. Lane, Richard A. Ronzio, Frederick N. Bender

Climax Molybdenum Co. operated a hydrometallurgical plant at Climax, Colo., from August 1966 to August 1968 to recover molybdenum from an oxidized ore. The feed, tailings from sulfide flotation, was first upgraded by cycloning. The concentration plant handled 6000 tpd of feed and produced 2000 tpd of slime concentrate. The concentrate was leached by a sulfuric-sulfurous acid solution at 65°C. The molybdenum was solubilized in the form of "molybdenum blue." Activated charcoal was added to the leach tailings in a resin-in-pulp type circuit. Molybdenum was adsorbed on the charcoal. The charcoal was screened from the pulp and washed. The washed charcoal was pumped to columns where it was ammoniated and air-blown. The oxidized molybdate then was washed from the charcoal. The eluate was evaporated until ammonium dimolybdate crystallized out. The ammonium dimolybdate was calcined to molybdenum trioxide.

Jan 1, 1973

By John W. Lane

Climax Molybdenum Company, a Division of American Metals Climax, Inc., operated a hydrometallurgical plant* at Climax, Colorado from August 1966 through August 1968 to recover molybdenum from a mixed oxide and sulfide ore. The ore treated for this addition to the existing plant contained sufficient Molybdenite values to be mined for Molybdenite recovery alone, so that the oxidized molybdenum recovery could be regarded as a byproduct operation. Climax is located at an elevation of 11,300 feet. All process equipment, except thickeners, was enclosed in buildings. Annual snowfall is approximately 250 inches per year. Paved highways and rail service to the plant are maintained and kept open all year. Most of the employees live in the town of Leadville, which is approximately twelve miles from the plant site. The sulfide flotation plant handles 40,000 to 45,000 tons per day of ore. The mine is one of the world's largest underground mines.

Jan 1, 1971

By Blaskett K. S

The physical properties of monazite and the minerals with which it is associated in east coast beach sands are studied and discussed. Possible means for improving recovery are examined. In particular, it is suggested that the practice of splitting the heavy mineral concentrate into two parts as a preliminary to treatment in separate "rutile" and "zircon" mills can be modified in a simple fashion by the addition of an extra magnetic separation stage so as to aid monazite recovery.INTRODUCTIONBeach sand deposits on the east coast of Australia are a major source of rutile and zircon, and supply 80 per cent or more of world requirements. The deposits also contain a small amount of monazite, averaging about 0.5 per cent of the total heavy minerals. Yet despite a steady price in recent years of £150-160 per ton, monazite production has remained relatively small.On the basis of rutiIe production, potential monazite production on the east coast was about 1,500 tons in 1956, but only 102 tons of high-grade concentrate was produced. The main deterrent to increased production has probably been the capital cost of the necessary equipment. Separate electrostatic and magnetic equipment and separate table concentration and drying constitute a considerable outlay for a by-product contributing 4 to 5 per cent of the revenue from rutiIe.It is the purpose of this paper to discuss monazite concentration generally and to suggest modifications to flowsheets, which may facilitate monazite production while maintaining the main objective, simple and cheap means for maximum rutile production.

Jan 1, 1958

By Hideaki Tokuyama

Recovery of Ni from acidic wastewater of metal surface treatment has been investigated for reuse of the metal and water. Ion exchange equilibria between Ni ion and a strong acid cation resin, DIAION SKIB, and effective diffusivity in resin particle have been studied and they related to the concentration of HCI. The amount of adsorbed Ni for unit quantity of resin decreases with the increase in HCI concentration. This trend is remarkable for acid concentration above 0.1 kmol/m3,. The exchanging ratio of Ni2+ to H+ in resin particle is I/2 and the values of equilibrium coefficient K and maximum exchange capacity Q are I.62 and 3.16 keq/m3 -dry resin, respectively. Effective diffusivity D. determined from the observed breakthrough curve increases with increasing concentration of DC!. A prototype of moving bed has been developed and applied for the recovery of Ni from model solutions of wastewater prepared by mixing HCl and NiCl2. This apparatus allows us to control the resin flow rate by changing the cross sectional area of hole I the Teflon plate installed at the bottom of resin bed. Characteristics of Ni recovery have been clarified under various liquid flow rates. In any case for Q1, Ni ion has been effectively recovered on SKIB resin and the removed fraction was more than 99.5 %. Higher loading ratio of ion is attained at larger liquid flow rate.

Jan 1, 2003

By Hui Wang

With the great increasing use of nickel metal hydride batteries recently, the waste of this kind batteries have been paid for close consideration. For the main reason that the waste of the batteries contained precious metals and lanthanide which cost great lose. This paper introduces the pyrometallurgical process of recovering nickel and cobalt from the waste of the nickel metal hydride batteries. Particularly, the waste for the process was from factory during the producing program. The use of designed solvent to divide nickel and cobalt in melted state from the waste is described. Also, the result of the nickel and cobalt and melted gangue that mainly consist of lanthanide oxide are included in details. The aim of the paper is to find out a simple and feasible way to reuse waste from nickel metal hydride batteries.

Jan 1, 2009

By Monica M. Jimenez Correa, Jorge A. Soares Tenorio, Denise Crocce Romano Espinosa, Paula Aliprandini

The surface zone of nickel laterite ore is generally considered as residue. However, because of the depletion of ore sources and the increase in demand, this previously discarded zone may now be processed economically for nickel and cobalt. After leaching and removal of the impurities, the solution contains cobalt, magnesium, manganese and nickel. Solvent extraction is a hydrometallurgical technique used in the separation of metals from aqueous solutions. Cyanex 272 and D2EHPA are extractants used to separate nickel from cobalt. The mixture of extractants can change the performance during the metals extraction. This work aims to evaluate the solvent extraction of nickel and cobalt when Cyanex 272 and D2EHPA are mixed. The results showed that the increased concentration of D2EHPA in the organic phase increased the extraction of nickel and magnesium. However, cobalt extraction was reduced and the manganese extraction was not altered.

Mar 1, 2018

By A. Deepatana

This study compares the use of an aminophosphonate chelating resin Purolite S950 and a sulphonic acid strong cation exchange resin Purolite C160H to recover nickel and cobalt from the synthetic bioleach solutions. Batch adsorption of metal citrate is performed as a function of metal citrate concentration (15~2000 mg/L) and solution pH (0.01M and 0.1M citric acid). The adsorption mechanism as inferred from the fit to Langmuir (LM), Freundlich (FM) and Redlich-Peterson (RP) models demonstrates that nickel citrate adsorbed onto C160H appears monolayer in comparison to that adsorbed onto S950 exists multilayer. In contrast, cobalt citrate adsorption onto both C160H and S950 agrees with the LM model. The results have shown that loading capacities of nickel and cobalt citrate onto C160H are 60 and 65 mg/g whereas those observed onto S950 are 16mg/g and 6 mg/g respectively. These are achieved in metal citrate prepared in 0.1 M citric acid. Resin regeneration is conducted in using 2 M nitric acid solution. The results show high efficiency of nickel and cobalt citrate elution from Purolite C160H. Findings from this study suggest Purolite C160H is a suitable adsorbent for recovering nickel and cobalt from bioleaching solutions.

Jan 1, 2014

By Qian Xu, Guangshi Li, Xionggang Lu, Xingli Zou, Hongwei Cheng, Cong Xu, Changyuan Lu

The roasting of nickel-bearing sulfides is a complex but important process which has not been adequately characterized. Combination of X-ray diffraction and scanning electron microscopy has been proved to be useful for such experiments. The leaching results of nickel, copper, iron and cobalt was analyzed by ICP methods. Process possibility of polymetallic sulfide concentrates through a three-step procedure (oxidation roasting - chlorination - water leaching) was suggested. Ammonium chloride could react with nickel/copper oxides to produce intermediate complexes. At the temperature range of 280~340 oC, these complexes further decomposed to the corresponding simple chlorides. Roasting sulfide concentrate using NH4Cl is effective for complex ores.

Jan 1, 2016

By P. Tim Johnson

Relentless increases in demand for nickel and vanadium for uses such as steelmaking, catalysts and battery materials, plus the growing financial and environmental costs of their primary extraction, have led to much interest in potential secondary sources of these metals. The presence of such metals in heavy fuel oils, bitumen and related materials offers both opportunities and challenges for potential extraction methods, especially with the growing production and importance of metal-rich fossil fuels around the world. For several decades, Tetronics’ DC plasma smelting technology has been used for the recovery of metals such as nickel and chromium from stainless steel melt dusts and other wastes in compact, environmentally-friendly and efficient plants. This paper explores the suitability of DC plasma smelting as part of a wider flowsheet with feed preparation and aluminothermic reduction techniques for smaller-scale extraction operations based on this important niche secondary source of these key metals.

By R. B. Sudderth, C. R. Merigold

Greater, emphasis is being placed on recovering nickel from laterite ores by ammonia leaching techniques. New methods are required for lower cost, non-polluting techniques to separate more efficiently the metals of interest. Liquid ion exchange techniques meet these requirements with the added advantage of producing salable electrowon nickel cathodes at the plantsite. A complete solvent extraction- electrowinning process is described, including preliminary engineering and cost data for a typical plant producing 50 million pounds of nickel per year.

Jan 1, 1973

By Kim Verbeken, Evelien Van de Steene, Marc Verhaege, Jeriffa De Clercq

"AbstractThe industry is confronted with stricter discharge levels and an increasing awareness to avoid toxic waste (such as heavy metal containing sludge obtained in physicochemical water treatment) and recover valuable metals. This can be realized by ion exchange or by electrodeposition. Both techniques however show an optimum concentration range to efficiently remove and/or recover metals: electrolysis can recover the metal in its metallic form but suffers from low efficiency when applied to diluted solutions, whereas ion exchange can only be applied economically in the low ppm range.A combination of ion exchange followed by electrodeposition was applied to an industrial wastewater. The strong acidic ion exchange resin was stripped with H2SO4 giving a solution of 9g/L nickel. From this solution, nickel was electrodeposited in an ammonia buffer on a Ti-mesh cathode with high current efficiency. It is shown that organic compounds (surfactants, brighteners, …) present in the industrial wastewater do not influence the recovery process.IntroductionAlmost all rinse waters emerging from metal plating plants are generated during the washing operation of plated materials. These solutions with low metal content must either be recycled within the process or be discarded to the surface water after decreasing their metal content to acceptable levels determined by the local environmental regulations, which become more and more stringent. Today, the most commonly used practice is a physico-chemical treatment (precipitation) and a resin post treatment to meet the standards. A more sustainable approach should use a technology to recover efficiently the metal or metal salt without the production of sludge and the effluent should be consistent with environmental regulations."

Jan 1, 2008

By Beatriz Amarai Campos, Jorge Alberto Soares Tenorio1, Denise Crocce Romano Espinosa, Adriana Johanny Murcia Santanilla

"The aim of the present work is to investigate the recovery of nickel from obsolete cell phones printed circuit boards. The printed circuit boards were firstly submitted to a grinding process and then leached in sulfuric acid. Nickel was extracted from aqueous solution using Cyanex 272. Aqueous/organic ratio was 1/1. The effect of both pH and modifier addition on selectivity of extraction was investigated.IntroductionCurrently, electric and electronic equipments (EEE) have become a necessity to the modern life. Associated with this necessity comes the continuous and increasing replacement of those equipments by new ones. The accelerated technology advances are responsible for the generation of electric and electronic waste. This waste can be dangerous not only to human health but also to the environment. Waste of electric and electronic equipments (WEEE) has a variety of components and metals in its composition becoming a potential pollutant to the environment when not properly discarded. Its wrong disposal causes a loss of materials that could be recovered and reused. Therefore WEEE treatment is an important matter because it can assist the reduction of waste generated and the recovery of valuable metals.Printed circuit board (PCBs) is an essential component of EEE and is typically very complex from a chemical point of view. Several metals may be present in its composition, such as cooper, nickel, iron, zinc, lead, tin and silver1''. This characteristic hinders the development of a simple treatment, making it necessary the application of chemical and mechanical processing for their recycling'4'. The UN estimates that approximately 20 to 50 million of tonnes of WEEE are generated worldwide each year."

Jan 1, 2011

By F. Barriga-Ordonez, J. A. Finch, L. Calzado, S. R. (Ram) Rao

Sludge, formed by lime treatment of acidic drainage and stored in tailing ponds of the Sudbury region, contains 5-7% Ni, mostly in a mix of hydroxides with Fe (~ 10%), Mg (~ 10%) and Cu (-0.5%), and Ca (-3.5%) as sulphate. Investigations were conducted to recover nickel by a 2-stage process. In the first stage, the sludge was leached with sulphuric acid at pH 3.2. About 90% of the nickel was extracted, producing a solution, which contained mainly nickel (2 g/L) and magnesium (3.7 g/L). In the second stage, nickel was separated by treating with ozone which recovered 99% of the nickel in the Ni(III) oxidation state as -85% pure nickel oxide-hydroxide (NiOOH) precipitate. The oxide settled and filtered readily. A potential use of the product in battery making is suggested. The leach residue contained 0.5% Ni making it less toxic for disposal. Some physical properties of nickel oxy-hydroxide and process parameters including ozone consumption will be discussed.

Jan 1, 2005

By Mikiya Tanaka, Mikio Kobayashi, Mansour A. S. A1Ghamdi, Kenji Tatsumi, Yukinori Saiki, Hirotaka Senba

"In order to recover nickel ion in a spent electroless nickel - phosphorus alloy plating bath and, at the same time, to remove impurities such as iron and zinc, the applicability of solvent extraction with LlX84I as the extractant has been investigated using actual spent solution. Although the extraction efficiency of nickel from the spent solution is considerably lower than that from the nickel sulfate-nitrate solution, nickel in the spent solution is selectively extracted with high efficiency at the pH of 6 - 7. The extracted nickel is effectively stripped by sulfuric acid at a pH of less .than· 3. On the basis of these results, a· flowsheet for recovering nickel from the spent solution is proposed Chemical equilibrium calculations of the spent solution has shown that the complex formations of nickel with anions such as lactate and phosphonate ions become predominant in the pH range between 2 and 6. This results in the depression of nickel extraction efficiency from the spent solution as compared with that from the .nickel sulfate-nitrate solution. By combining these aqueous equilibrium calculations with the· extraction model considering the extraction stoichiometry and the aggregation of the extractant in the organic phase, the extraction behavior of nickel is quantitatively predicted.IntroductionElectroless plating is indispensable for the recent advanced industries such as the electronic and mechanical industries. Electroless plating baths are repeatedly used by supplying the metal salts; however, the accumulation of the counter anions of the metal ions, the components formed by the oxidation of the reducing reagents in the plating baths, and the metal ions as impurities dissolved from the surface of the objective materials degrades the· quality of the plating. Thus, the baths are finally treated by a precipitation method to form a large amount of metal sludge, which is disposed in dumping sites. Therefore, from the standpoints of environmental protection and resource preservation, it is highly desired to establish a recycling process of the plating baths with minimum emission. Solvent extraction seems to be one of the 'suitable methods to recover metals from the spent electroless plating baths, because the concentration of the metal ion in the baths is relatively high, which is advantageous to solvent extraction as compared with the ion-exchange and adsorption methods. Some studies about the application of solvent extraction have already been carried out using simulated spe11t electroless plating baths [1-3]."

Jan 1, 2000

By J. L. Holman

The Bureau of Mines is investigating recovery of Ni, Co, Cr, and other metals from mixed contaminated supera110y scrap. The scrap is melt-refined and cast into anodes for electrodeposition of recyclable Ni-Co alloy. Melt oxidation using roasted superalloy grinding sludge as oxygen source can divert the Cr to the slag but with excessive Ni-Co loss. Melt oxidation-carburization or direct melt carburization retains -95 pct of the Ni-Co in the anode alloy. With direct carburization, -90 pct or more of the Cr and other refractory metals report to the anode alloy, largely as carbide phases insoluble in electrolysis. Electrorefining data relate parameters such as controlled cathode potential, Fe and Cr impurities, pH, and compartmented cell use, to current efficiency and Ni-Co deposit quality. Recovery of -90 pct of the Ni-Co in the scrap can be achieved. Preliminary experiments to recover Cr, W, and other metals from the anode sludge and other byproducts are discussed. 347

Jan 1, 1987

By H. Pempel, J. Markowski, P. Ay

"Metal-coated thermoplastic parts find more and more functional and aesthetic applications in the interior and exterior of cars. The vapor-deposited or electroplated coatings are usually composed of a plurality of nickel- and chromium-containing layers, which are applied to copper-containing carrier layers on the polymers. Previously, recycling processes are mainly focussed at the recovery or thermal utilization of the plastics. Targeted and selective recycling of the metallic coatings is usually not carried out. Together with several SME, BTU developed a process, in which a complete and separate recovery of all components in high purity is possible with biotechnological methods. The bioleaching is carried out with iron and sulfur-oxidizing bacteria, especially Acidithiobacillus ferrooxidans. The copper-containing layers are dissolved in the solution; chromium- and nickel-containing particles are precipitated as solids. After the bioleaching, a mechanical separation of the individual metal-containing components and their separate workup are carried out. End-products are metallic copper, a nickel- and chromium-containing solid and the cleaned plastics. The bioleaching ensures a high purity of the end products. Through the use of bacteria, which are also found in nature, the process is environmentally friendly. Compared to chemical leaching using inorganic acids, considerably shorter leaching times can be achieved. In addition to the optimization of the leaching process, the R/D-project also includes the development and testing of the apparatus technology.INTRODUCTION The material complexity of many end-user products has increased in recent years, especially in the fields of electrical appliances, vehicle technology and medical technology. However, the demands on functionality, safety, comfort and energy efficiency still play a greater role in product design as factors such as sustainability and usability. For example, if a car still holds more than 70% of steel in the 1980s, a vehicle nowadays includes a larger proportion of a variety of difficultly separable plastics and composite materials, as well as complex metal composites. This relates in particular to composites made from such different materials as metals and plastics. The processing and recovery of the components of those complex material mixtures is difficult for recycling companies."

Jan 1, 2017

By David B. Spencer

This paper describes a process for separating non-ferrous metals such as aluminum, copper and zinc, from other residential and industrial waste by means of permanent magnets. Although the separator may be used in the recovery of non-ferrous metals from auto scrap, most of the testing to date has been aimed at recovery of non-ferrous metals from municipal solid waste, especially recovery of aluminum from the heavy fraction of a resource recovery plant. In most resource recovery plants the incoming solid waste material is first shredded and then air classified into a light and a heavy fraction. The light fraction which contains mostly paper, cardboard, etc., can be used either as a fuel for power generation or in the production of new paper products. The heavy fraction which remains consists mostly of glass, ceramics, wood, ferrous metals and non-ferrous metals. The ferrous metals may be removed from the heavy fraction by conventional magnetic separators. After primary shredding, most of the glass and ceramic is fine in size and may be screened away leaving a residue of wood, cardboard, and non-ferrous metals. This residual heavy fraction is the input material for the separator described in the present paper.

Jan 1, 1975

By Clyde S. Brooks

This paper undertakes to assess what opportunities exist for the economical recovery of non-ferrous metals from spent catalysts. The most promising recovery appears to lie with metals such as Co, Mo, Ni, W, heterogeneous catalysts used on a large scale in petroleum processing. Nickel is a metal with diverse applications on a large scale notably in hydrocarbon steam reforming and in vegetable oil hydrogenation. In addition, several of the precious metals, notably Pt, Pd, and Rh, find extensive use in fossil fuel processing and in automotive and power plant flue gas control. The hydrometallurgical and pyrometallurgical alternatives for processing are identified and discussed, especially with citations to illustrate reduction to commercial practice. Promising directions for adaptation of appropriate, economic separation technologies for recovery of non-ferrous catalytic metals generated in significant amounts for the secondary metal markets are identified. Recycling

Jan 1, 2000

By E. Martinez

A heavy mineral sand sample was tested containing 13% heavy mineral consisting of rutile, zircon, and ilmenite. Eleven tests were run at a mill site with a Mineral Deposit Limited MG 4 spiral to determine the effect of the addition 0; magnets to the spiral compared to conventional gravity separation. Different magnet configurations and field strengths were tested. Optimum results were obtained with the spiral retrofitted with magnets. The heavy mineral content of the concentrate was increased from 55.5% in the control to 64.2% with the magnets. The 8.7% improvement in heavy mineral recovery was due not only to the weakly-magnetic ilmenite, but also to increased recoveries if the non-magnetic zircon and rutile. The increased recoveries were achieved with no loss of concentrate grade.

Jan 1, 1992