Preliminary List of Abstracts (Alphabetical Order)

1ST INTL. SYMP. ON RARE EARTH AND PLATINUM GROUP METALS:MANAGING AND PROCESSING

Chalmers Tekniska Hoegskola (Chalmers University of Technology) was founded in 1829 following a donation by William Chalmers, director of the Swedish East India Company, and it was transformed into an independent foundation in 1994. Recycling issues have come more and more in focus in recent years. All needs to be recycled, from plastic bottles to nuclear waste, in order to achieve a sustainable society. What is not so often realized is that most recycling issues are composed of many different questions ranging from highly technological to purely philosophical or including behavior science. At Chalmers, the recycling activities started already in the 50ies and 60ies when Professor Jan Rydberg was making pioneering work on separation and recycling of metals with high purity from different waste fractions. The main method used then and now was hydrometallurgical methods. In the early 60ies, a well-known apparatus, named AKUFVE and an extended version SISAK-technique have been invented.The group has evolved along the years but the red line has been kept: Recycling and separation of metals by means of solvent extraction mainly from nuclear waste have been conducted.A dedicated professorship and the first PhD student for Industrial Materials Recycling started in 2007 and in 2012 a second professorship in the same area was promoted. A Competence Center for Recycling (CCR) has been started, where a much wider know-how competence bank has been gathered (e.g. Biology, toxicology, physics, practical philosophy and others), thus ensuring a broad, cross-cutting approach to such complex subject.The current group has several well equipped laboratories for work with radioactive isotopes, high temperature chemistry, ash treatment, solvent extraction (from basic to pilot scale research) and recycling of nuclear waste and nuclear fuels research by means of hydrometallurgical methods. Also, a corresponding fleet of analysis techniques is existent as well.The newest research interest of the recycling branch of this group is: Batteries (e.g. Hydrometallurgical treatment of NiMH batteries - the first ever graduate PhD in the field of Industrial Materials Recycling); WEEE (recycling of REMs from phosphors from lighting products; Recycling of ITO and REMS from LCDs; Recycling of REMS from CRTs, recycling of magnets from different electronic devices), industrial waste spills (e.g. CIGS solar cells sputtering waste). All the above projects will make the subject of this lecture, where new methodology and advances in recycling of REMs will be largely discussed.

In this laboratory scale research, the extraction of scandium from a lateritic nickel-cobalt-scandium ore was investigated. After the physical, chemical and mineralogical characterization of representative lateritic ore sample, the optimum conditions of sulfuric acid pressure leaching were determined by using a 2-liter titanium autoclave. Temperature and duration of leaching, addition of acid amount, particle size and oxidation-reduction potential (ORP) control by the addition of sulfur were among the parameters studied there. The experimental findings indicated that about 90% of the nickel and cobalt and 80% of the scandium present in the lateritic ore studied could be extracted under the optimum conditions determined experimentally.

Nowadays, energy efficiency and renewable energies are central concerns to develop sustainable energy. Among the diversity of technologies, Proton Exchange Membrane Fuel Cells (PEMFCs) represent a promising alternative to cater for energy requirements in the next decades. PEM fuel cells release electrical energy through two electrochemical reactions performed on platinum nanoparticles supported on carbon and separated by a polymer membrane. Currently, the commercial membrane electrode assemblies (MEAs) contain a Pt-loading between 4 mg.cm-2 and 0.15 mg.cm-2. This loading represents 0.5 % to 2.0 %wt of catalytic element in the MEAs. It is widely accepted that the high cost and limited supply of platinum are considered as issues to large scale commercialization of PEMFCs. To overcome these hurdles, the strategies aim at reducing the Pt-loading for minimizing the system cost and recovering the platinum to secure the platinum supply. The conventional approach to recover platinum from MEAs includes a pyro/hydrometallurgical process combusting the PEM and the carbonaceous diffusion layers, dissolving the resultant ash in aqua regia and purifying the precious metal using standard refining.In this study, we put forward a hydrometallurgical approach to recover 80% platinum from MEAs by a separation of the membrane and catalyst layers, lixiviation and recovery by precipitation. The residual platinum in solution (2g/l) was treated by ion exchange resins (IERs). A large study has been dedicated to define the most suitable resin among three different resins. The IERs have been studied in unequilibrium and equilibrium conditions of sorption. The prediction of the rate-limiting step and kinetic parameters were investigated. Moreover, the Langmuir, Freundlich, and Temkin-Pyzhev isotherm models were applied. These data are critical for defining the best conditions for sorption and design appropriate sorption treatment plant. Finally, desorption has been studied regarding: Nature, concentration, pH and ionic strength of the solution.

For many companies, understanding the environmental impacts of their products and operations is rising up the business agenda. Business drivers include: - Legislation on energy consumption, hazardous substances and conflict minerals. - Volatile material and energy prices. - Product marketing, brand value and Corporate Social Responsibility- Stimulus for product innovationDespite these significant and growing pressures, many companies have not yet been able to implement systems or tools to effectively manage the environmental issues associated with the product they develop.It is acknowledged that approaches such as Life Cycle Assessment (LCA) generally require significant knowledge and expertise, both to perform the analysis and to understand the results. Furthermore, the LCA approach is substantially divorced from product development activities as it is generally applied at the end of the product development process. This results in poor engagement of designers and engineers with environmental issues and a general lack of support (or capability) to address these issues within the organisation.This paper introduces an on-going, industry-based project that is attempting to overcome these implementation barriers by adopting a risk-based approach to the management of product sustainability issues. Working with partners from the aerospace, defence and security sector, the project aim is to integrate product sustainability into the strong culture for business risk management that already exists within companies in this sector. By presenting product environmental sustainability issues in terms of the business risks they engender and by integrating with existing business risk management systems, it is believed that a business risk-based approach will result in a wider understanding of environmental issues and ultimately result in these issues being managed as a normal part of the engineering design process.

In this talk, we present a new class of stable metallic nanostructural materials combining nanoscale porosity and nanoscale crystallinity. We report a low temperature chemical synthetic way enabling preparation of stable nanostructural metals and their alloys. Based on numerous examples of pure metals and binary alloys of platinum group, we show that the proposed route provides tight control over morphology (down to nanometer scale), chemical composition (ratio of metallic elements) and phase composition of final metallic material. We found that the crystallite size of an alloy/metal and the smallest size of a pore are both affected not only by a preparation temperature, but also by a number of coexisting crystalline phases. The phase composition of binary alloys is very close to the thermodynamic equilibrium for eutectic and peritectic-type systems (Rh-Ru, Ir-Pt, Ir-Ru, Ru-Pt). The unique porous structure of the presented new metals is composed of interconnected nanoscale metal ligaments interpenetrating with the pores whose size ranges from a few microns down to a few nanometers. The free volume occupies more than 90% of the total material volume. Pores and metal ligaments exhibited obvious features of self-similarity over the whole observed structural size range. To sum up, with the characterization data obtained at the presented new materials, we can discuss their possible applications for fundamental and research purposes. We will also discuss the expected implications of a proposed preparation path which, in our opinion, can be considered as "a cold alternative" to a traditional "hot" melting-solidification preparation of alloys.

Phase equilibria in the DyBr3-MBr (M = Li, Na, K, Rb, Cs) binary systems were established by differential scanning calorimetry (DSC). The composition of eutectics was always determined by the Tamman method.The DyBr3-LiBr phase diagram exhibits two eutectics and has two stoichiometric compounds. The first compound, Li3DyBr6, melts congruently at 803 K. The second one, Li6DyBr9, decomposes in the solid state at 656 K. The composition of two eutectic mixtures was determined as x(DyBr3) = 0.156 (787 K) and 0.321 (791 K). The DyBr3-NaBr phase diagram exhibits incongruently melting compound Na3DyBr6 and one eutectic located at DyBr3 molar fraction x = 0.409 (T = 711 K). Na3DyBr6 undergoes a solid-solid phase transition at 740 K and melts at 762 K. The DyBr3-KBr phase diagram exhibits two eutectics and two stoichiometric compounds. The first compound, K3DyBr6(s), undergoes a solid-solid phase transition at 694 K and melts congruently at 991 K. The second one, K2DyBr5(s), melts incongruently at 733 K. The compositions of two eutectic mixtures were determined as x(DyBr3) = 0.159 (886 K) and 0.454 (689 K). The DyBr3-RbBr phase diagram exhibits two eutectics and three stoichiometric compounds. The first compound, Rb3DyBr6(s), undergoes a solid-solid phase transition at 726 K and melts congruently at 1059 K. Rb2DyBr5(s) melts incongruently at 737 K and RbDy2Br7(s) at 748 K. The compositions of two eutectic mixtures were found to be: X(DyBr3) = 0.116 (886 K) and 0.458 (702 K). The DyBr3-CsBr phase diagram exhibits two eutectics and two stoichiometric compounds. The first compound, Cs3DyBr6, undergoes a solid-solid phase transition at 724 K and melts congruently at 1086 K. The second one, Cs3Dy2Br9, melts incongruently at 891 K. The compositions of CsBr-Cs3DyBr6 and K3Dy2Br9-DyBr3 eutectic mixtures were determined as x(DyBr3) = 0.102 (T = 862 K) and 0.579 (T = 795 K), respectively.

Rare Earth (RE) metals are used as various functional materials, including permanent magnets, hydrogen storage alloys and luminescent materials. The consumption of neodymium (Nd) and dysprosium (Dy) is increasing dramatically because of an exceptionally high demand for Nd-Fe-B-(Dy) magnets and a significant amount of the magnets is wasted. Therefore it is important to develop a recovery process of the elements from the wasted magnets.In order to design a recovery process, the thermodynamic information of Nd and Dy in iron (Fe) -based alloys is necessary. The thermodynamic information was measured by double Knudsen cell mass spectrometry at high temperature. The Gibbs energies of formation of the intermetallic compounds between Nd and Fe, and Dy and Fe were estimated.The activity of Nd in Fe/Nd2Fe17 equilibrium at 1473 K is calculated to be 0.15, that of Dy in Fe/Dy2Fe17 equilibrium to be 0.0057 with the estimated data. Using this difference, a new recovery process was designed. In the recovery process, Nd is extracted from the magnets containing Nd and Dy by silver (Ag) at high temperature. Nd is separated as Ag-Nd alloy form magnet, which is Fe-based alloy with Dy. Nd and Dy are recovered and separated at once. The process was demonstrated in this study. Wasted magnet and Ag in a graphite crucible were charged and heated in inert Ar atmosphere in an electric resistance furnace. Nd can be extracted about 80 mass% by Ag rapidly, although only 20 mass % Dy was extracted in the same experimental condition. And Nd was recovered from Nd-Ag alloy by hydrochloric acid leaching.

The usage of rare earths in industries keeps increasing due to their key roles as alloying element. However, the supply is going to be limited, since the elements are produced locally with severe problem of contamination, which is also connected even to its recycling process generally done by chemical process. In this talk, a pyro-recyling process will be introduced, in which the rare earth selectively is extracted by Mg, a typical low melting element. The product recycled is Nd-Fe-B, a typical composition of permanent magnet. Also, a concept of total recycling where each element input for recycling process connects to materialization will be introduced.

For the recovery of rare metals from urban mine, pyrochemical approaches such as fluoride or chloride processes have potentials for waste reduction and effective recycling. In this paper, advantages of fluoride and chloride processes are introduced based on the experimental study. Separation of refractory metals such as tantalum and niobium are also examined by fluorination or chlorination methods. Finally, the applicability of halide processes to rare metal recycling is discussed.

With the rapid advancement of technology, the demand for elements such as rare earth metals (REMs) has increased considerably during the last decade. Many countries are facing problems securing sustainable supplies, a fact acknowledged in many publications. Due to the ever-growing demand and supply problems, REMs are now considered to be some of the most critical elements. This has focused attention towards their recovery from end-of-life products and industrial waste streams, with fluorescent lamps being one of the targets. However, despite the research published on the recovery of REMs from fluorescent lamp waste, large scale applications are scarce, mainly due to the lack of sustainable processes.The research presented here is aimed at developing a sustainable hydrometallurgical process for the treatment of fluorescent lamp waste, with the goal of recovering the REMs that these lamps contain.In comparison to other efforts in this field, these investigations were carried out using real waste samples originating from a discarded lamp processing facility. The complexity of the material (a mercury contaminated mix of glass, metallic and plastic parts, phosphors, remaining electronics and other impurities) makes already proposed methods a challenge and makes additional research necessary. Cerium, europium, gadolinium, lanthanum, terbium, and yttrium were the REMs identified in the studied material. The leaching of metals was investigated using organic and mineral acids under various conditions (temperature, ultrasound-assisted digestion, solid to liquid ratio, and leaching agent concentration). Partial selective leaching of europium and yttrium is possible using diluted mineral acids at room temperature. An increased acid concentration and increased temperature, and also ultrasound-assisted digestion improved the leaching efficiency for the other investigated REMs. The recovery of REMs from nitric acid media was studied using commercial trialkylphosphine oxides. The extraction potential of REMs and the advantages/disadvantages for a possible industrial scale-up process were investigated. The separation of heavier elements (terbium, yttrium, europium and gadolinium) from lighter ones (cerium and lanthanum) is possible due to larger separation factors. A selective stripping of REMs from the co-extracted elements (iron and mercury) was easily achieved using concentrated hydrochloric acid. Further recovery of the extracted iron and mercury (with either oxalic acid or nitric acid solutions) allows the subsequent re-use of the organic phase in the process.

The recycling and recovery of Platinum Group Metals (PGMs) provide a vital source of metal supply, accounting for around 25% of all PGM supply in 2012. Its increasing importance over recent years is illustrated by a c.80% growth in recycled supply of PGM compared to a 17% fall in primary production between 2005 and 2012.Part of this upward trend in recycling has been a result of an increase in the adoption of Tetronics DC plasma arc PGM recovery technology, which delivers industry-leading technical recovery rates for a wide range of PGMs recovered from spent automotive and industrial catalysts at both a pilot and full commercial scale. In common with many other metals, recycling of PGMs not only leads to greater re-use of these critical metals with production of the metals closer to the ultimate end-use, but it also has excellent environmental credentials in terms of the consumption of energy/materials and the generation of secondary waste streams when compared to typical primary production routes. This paper presents the latest developments of Tetronics plasma-based PGM recovery technology with a particular emphasis on its environmental performance, including the consumption of electricity, water and gases, emissions to air and residual wastes. This performance will be compared to the typical environmental impact of the primary production of platinum and other precious metals as reported in the open literature along with the implications for production costs and other plant requirements. The paper will also assess the benefits of this technology for the recovery of precious metals from other rapidly-growing waste streams, such as electronic wastes and ore-concentrates.

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