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The intensive development of industry, especially the mining and metallurgy, automotive and electrical industries, as well as the growing demand, rapid consumption and "ageing" of most products, including electrical/electronic equipment, requiring regular replacement, affects the amount of Potentially Toxic Elements (PTE), including Technology Critical Elements (TCE) in the environment. This preliminary study focuses on the following TCE: Ga, Ge and Tl. The main thing they have in common is that they have not been much studied and the level of knowledge concerning the environmental impact of their use is quite slight. Additionally, content of more common PTE (As, Cd, Cu, Pb, Sb, Zn) was determined in order to discover some relationships between these both group. Soil samples were collected from topsoil (0-5 cm) and subsoil (

The article draws attention to the problem of the presence in waste electrical, electronic equipment (WEEE) of selected metals from the group of critical metals (germanium), strategic metals (tellurium) and highly toxic elements (thallium). Due to low content of these metals in e-waste, they are usually ignored during e-waste analysis, therefore they belong to the least-known metals in the literature. Their presence in WEEE can cause them to be concentrated in the environment during improperly e-waste processing. In the article the important applications of Ge, Te, Tl in electronic equipment, quantities identification of these metals in a variety of electronic equipment elements, paying special attention to the ability to accumulate/concentrate Ge, Te, Tl in individual fractions after the e-waste shredding and grinding process are presented. This approach is aimed at determining the possibility of these metals getting into the environment, during the storage and processing of e-waste (especially in the unit processes of disassembly, separation, shredding), in the case of uncontrolled electronic waste handling and disposal. The research project received funding from the National Science Centre of Poland on the basis of the decision number UMO-2018/29/B/ST10/01522.

The article draws attention to the problem of the presence of metals: germanium (Ge), tellurium (Te), thallium (Tl), and others (Cd, Ba, Co, Mn, Cr, Cu, Ni, Pb, Sr, and Zn) in selected waste of electrical and electronic equipment (WEEE). As a result of the growing demand for new technologies, the global consumption of TECs has also been increasing. Thus, the amount of metals in circulation, of which the impacts on the environment have not yet been fully understood, is constantly increasing. Due to the low content of these metals in WEEE, they are usually ignored during e-waste analyses. The main aim of this study was to determine the distribution of Ge, Te, and Tl (and other elements) in ground sieve fractions (1.0, 0.5, 0.2, and 0.1 mm) of selected electronic components (solar lamps, solar cell, LED TV screens, LCD screens, photoresistors, photodiodes, phototransistors) and to determine the possible tendency of the concentrations of these metals in fractions. This problem is particularly important because WEEE recycling processes (crushing, grinding, and even collection and transport operations) can lead to dispersion and migration of TCE pollutants into the environment. The quantitative composition of e-waste was identified and confirmed by ICP-MS, ICP-OES and SEM-EDS, and XRD analyses. It was found that Ge, Te, and Tl are concentrated in the finest fractions of ground e-waste, together with Cd and Cr, which may favor the migration of these pollutants in the form of dust during storage and processing of e-waste.

Chapter describes a possibility of recovery of metal ions (especially platinum group metals) from spent automobile converters by hydrometallurgical method. Also, the composition of the automobile catalyst is reported. Moreover, the results of leaching of metal ions from spent catalysts with organic and inorganic acids were presented. Carboxylic acids were considered as potential leaching agents for treatment of spent automotive converters. These acids show leaching potential towards base metals, and could be used in the first step of leaching prior to platinum group metals leaching in more stringent conditions.

The first ever calorimetric results of integral enthalpies of mixing of liquid Li-Pb-Pd alloys were investigated with the use of an MHTC 96 drop calorimeter. Five separate measurements were performed for such liquid alloys as (Li0.5Pb0.50)1−xPdx, (Li0.25Pb0.75)1−xPdx at 926 K, (Pb0.90Pd0.10)1−xLix at 1005 K, as well as (Li0.75Pb0.25)1−xPdx, and (Pb0.60Pd0.40)1−xLix at 1026 K. Based on the authors' own equations describing the excess Gibbs energy of binary Li-Pb, Li-Pd, and Pb-Pd liquid solutions, and the experimental values of integral molar enthalpy of mixing of liquid Li-Pb-Pd alloys presented in this work, the ternary interaction parameters were calculated. Finally, the values of molar thermodynamic functions of liquid Li-Pb-Pd alloys were calculated and presented in the form of tables and figures.

The integral enthalpy of mixing of the ternary Li-Pb-Pt system was measured using high temperature drop calorimetry. Four independent series of fixed mole ratios of Li to Pb equaled to 1/3, 1, 3, and Pb to Pt equaled to 4 were conducted at 1026 K. The measurements were divided into three continuous parts. Firstly, the calorimeter was calibrated by dropping the pieces of Pb, subsequently, pieces of the second component (Li or Pt) were added to form a binary alloy, and then the study of the integral enthalpy of mixing of ternary Li-Pb-Pt began. The thermodynamic results are characterized by negative deviations to the ideal solution in the entire measured concentration range. Based on the experimental data for the Li-Pb-Pt solutions and on the integral enthalpy of mixing of the binary Li-Pb, Li-Pt and Pb-Pt solutions the ternary interaction parameters were determined and presented.

The role of iron in metal-bearing waste bioleaching was studied. Four various types of waste (printed circuit boards (PCBs), Ni-Cd batteries, alkaline batteries and Li-ion batteries) were treated by bioleaching using the acidophilic bacteria A. ferrooxidans and A. thiooxidans (separately or in mixture). Role of main leaching agents (Fe3+ions or sulphuric acid) was simulated in abiotic experiments. Results showed that oxidation abilities of Fe3+ions were crucial for recovery of Cu and Zn from PCBs, with the efficiencies of 88% and 100%, respectively. To recover 68% of Ni from PCBs, and 55% and 100% of Ni and Cd, respectively, from Ni-Cd batteries both oxidation action and hydrolysis of Fe3+were required. The importance of Fe2+ions as a reducing agent was showed in bioleaching of Co from Li-ion batteries and Mn from alkaline batteries. The efficiency of the processes has increased by 70% and 40% in Co and Mn bioleaching, respectively, in the presence of Fe2+ions. Based on the results we suggest the integrated biometallurgical model of metal-bearing waste recycling in the effort to develop zero-waste and less energy-dependent technologies.

The application of green synthesis in the nano-science and technology is of great importance in the area of the preparation of various materials. In this work, three selected algal species Parachlorella kessleri, Dictyosphaerium chlorelloides and Desmodesmus quadricauda were successfully used for the preparation of silver nanoparticles (AgNPs). Presence of AgNPs was confirmed by UV-vis spectroscopy and transmission electron microscopy. AgNPs produced by P. kessleri had narrow size distribution and average sizes of 7.6 nm. However, nanoparticle production lasted for long time. Nanoparticle formation by D. chlorelloides was the fastest, although, their average sizes were 23.4 nm with broad size distribution. Nanoparticles produced by D. quadricauda had average sizes 23.9 nm but they were the least stable, aggregated and precipitated from solutions within 3 days. These results confirmed that the size distribution and mean diameter of the nanoparticles, crucial for various applications, can be controlled by the organism selection.

Praca sfinansowa ze środkow statutowych Wydzialu Inzynierii Materialowej i Metalurgii Politechniki Śląskiej (11/990/BK_16/0039).

The recovery of precious metals is necessary for environmental and economic reasons. Spent catalysts from automotive industry containing precious metals are very attractive recyclable material because as the devices. they have to be periodically renovated and eventually replaced. Among automotive catalysts withdrawn from use, these with metallic carrier constitute quite a big group. Metallic carriers are usually obtained from steel FeCrAl , which is covered by a layer of PGM acting as a catalyst. World literature describes a number of pyro-or hydrometallurgical methods used for recovery of platinum from used automobile catalytic converters. However, all methods, available in the literature, are used to recover platinum from ceramic carrier. This paper presents the new method of removing platinum from the spent catalytic converters applying lead as a collector metal in a device used to wash out platinum by using mangetohydrodynamic pump. The article includes the description of the methods used in modelling magnetohydrodynamic phenomena (coupled analysis of the electromagnetic, temperature and flow fields) occurring in this particular device for this kind of waste. The general phenomena and ways of coupling the various physical fields for this type of calculation have also been described. The basic computational techniques with a discussion of their advantages and disadvantages have been presented.

The recovery of precious metals is necessary for environmental and economic reasons. Spent catalysts from automotive industry containing precious metals are very attractive recyclable material as the devices have to be periodically renovated and eventually replaced. This paper presents the method of removing platinum from the spent catalytic converters applying lead as a collector metal in a device used to wash out by using mangetohydrodynamic stirrer. The article includes the description of the methods used for modeling of magnetohydrodynamic phenomena (coupled analysis of the electromagnetic, temperature and flow fields) occurring in this particular device. The paper describes the general phenomena and ways of coupling the various physical fields for this type of calculation. The basic computational techniques with a discussion of their advantages and disadvantages are presented.

Every new car should be equipped with the catalyst, which limits the amount of harmful chemical compounds such as NOx, CH and CO emitted to the air. Auto catalyst consists of the ceramic or metallic carrier, on which is the layer with Platinum Group Metals playing catalytic role. There are many methods using for recovery those valuable metals from spent auto catalyst, however evry of those methods have some limitations. Proces described in the article is the modified method of metal collector, which used magnetohydrodynamic pump. Rotary electromagnetic field generates in the liquid metal rotary current, which as a consequence washing out the PGM metals from the ceramic carriers. Considering the possibilities of commercialization of the described method, the energy balance was made. From that balance the energetic efficiency of the unit was determined and the analysis of the temperature distribution was shown thermographycally.

The objective of this work was to evaluate the influence of static, stirring and shaking conditions on copper, zinc, nickel and aluminium dissolution from printed circuit boards (PCBs) using the mixed acidophilic bacterial culture of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans. The results revealed that static conditions were the most effective in zinc and aluminium dissolution. Zinc was removed almost completely under static conditions, whereas maximum of nickel dissolution was reached under the stirring conditions. The highest copper recovery (36%) was reached under stirring conditions. The shaking conditions appeared to be the least suitable. The relative importance of these systems for the bioleaching of copper and nickel decreased in the order: stirring, static conditions, shaking.

In the paper the results of corrosion resistance tests on ZnAlMg alloys used as batch hot dip galvanizing baths are presented. The tests were carried out on ZnAl alloys with 7 wt.% Al with the addition of 3 wt.% and 6 wt.% Mg. Corrosion resistance of tested alloys was compared with corrosion resistance of the traditional zinc bath alloy. Corrosion resistance of the alloys was defined by comparative methods in two standard corrosion tests in neutral salt spray and in moist atmosphere containing SO2. Electrochemical parameters of the corrosion process were determined on the basis of potentiodynamic tests. It was determined that the alloy of ZnAl7 has better corrosion resistance than the corrosion resistance of the alloy of a traditional zinc bath and that the addition of Mg to the alloy increases the corrosion resistance.

This work presents the first-ever calorimetric measurements of the partial and integral mixing enthalpies of liquid Li Pd alloys. These thermodynamic properties were determined with the use of an MHTC 96 drop calorimeter. The measurements for Li Pd system were performed at four different temperatures (620 K, 723 K, 824 K and 926 K), up to a maximum palladium concentration equaled xPd = 0.39. The experimentally obtained values were negative in the entire studied concentration range. The values of the integral mixing enthalpies of Li Pd liquid alloys are less exothermic than these predicted by the Miedema model. The highest difference between the data obtained experimentally and those calculated by the Miedema model was about 9 kJ/mol for xPd = 0.39. The experimental data of liquid Li Pd solutions were elaborated with the use of the Redlich-Kister formalism and Sommer association model. A good correlation between experimental and calculated by both models results in the entire studied concentration range of Pd was observed.

This study presents the thermodynamic properties and phase equilibrium of Pb-Pd system determined both experimentally and theoretically. The integral mixing enthalpy of the Pb-Pd liquid solutions was found to be negative in the entire measured concentration range at 828, 929, 1005, 1026 and 1085 K similar as the activity deviation of Pb presented in the literature. A good correlation between the experimentally obtained results of mixing enthalpy and the available literature data was found. Moreover, a new thermodynamic description of the Pb-Pd system was proposed with the use of Calphad and Ab-initio methods based on the all available in the literature and determined in this study experimental data. Thermodynamic properties and phase diagram data calculated with the use of the optimised thermodynamic parameters elaborated in this work are consistent with the experimental and predicted results.

Today recovery of platinum from used auto catalysts has become a necessity due to great demand for this catalytic metal. There are many methods of recovering platinum from used catalysts on the market, one of them is the original collector metal method using the magneto-hydrodynamic (mhd) pump. This method is based on the continuous flow of the collector metal (lead) in the channel of the device, which can be obtained by using the mhd pump at the device operating temperature of 673 K. Proper selection of process parameters such as power frequency (25&ndash, 100 Hz), inductor current density (20 A, 40 A, 60 A), gaps between the inductor and the liquid metal channel (2,4,8), flow velocity, secondary voltage (19 V, 40 V, 60 V) ensures proper efficiency of the device. Some parameters were selected on the basis of numerical simulations, others were experimentally verified&mdash, the tests were carried out for different washing out times (600 s to 3600 s), and different secondary voltage and inductor supply frequency (25 Hz to 45 Hz). Platinum washing out efficiency of up to 98% was obtained with a relatively short washing out time and low values of secondary voltage and inductor frequency. To improve the efficiency of the process, the thermal efficiency of the device was increased by 8% by insulating the cover of the device. Further modifications to the process include changing the collector metal&mdash, preliminary studies show that the addition of lithium increases the extraction of platinum from thin catalytic layers as a result of reduced surface tension of the extraction liquid. The preliminary results of the PbLi alloy spread on platinum coated surface seem to be very promising.

The paper presents the first worldwide, original, thermodynamic measurements for Li Pt system. The partial and integral molar enthalpy of mixing of liquid Li Pt alloys was determined with the use of MHTC 96 drop calorimeter. The measurements for this binary system were carried out at four different temperatures (622 K, 722 K, 824 K, 926 K), up to a maximum platinum content equalled xPt = 0.34. The values of the integral molar enthalpies of mixing were negative in the entire studied concentration range. The experimental data of liquid Li Pt solutions were elaborated by the Redlich-Kister equation. This study has begun the experimental measurements of the Li Pt system.

This article discusses the issue of age management in organizations and presents research results concerning workers’ perceptions of the phenomenon. The aim of the research was to study the perceptions of Polish employees of various professional fields, check employees’ level of knowledge of the age management issue, determine the variables differentiating this knowledge and verify whether employees consider age management to be useful and how they perceive experienced workers. The first part of the article presents concepts explaining what age management is in the context of demographic changes in European societies. Age management is a term encompassing a range of methods aiming at the possibly most effective use of human capital in organizations, irrespective of employees’ age, so that their work is efficient, profitable for the company as well as satisfying for the workers themselves. Strategies referring to age management should consider the perspectives of the company, employee, job market policy and demographic and economic situation conditions. In the later part of this article, the authors present the results of exploratory research into the level of knowledge of age management, the way it is perceived in organizations around Poland, mostly in international corporations. The research included employees of business and budget sectors. Respondents answered questionnaire questions by estimating, on the Likert scale, how they assess age management measures taken in their workplace, the need to use experienced workers’ potential, etc. In the authors’ opinion, because of the importance of the problem of efficient personnel management and promoting and applying age management programs, it is necessary for both employees and managers to have awareness, knowledge and positive attitude towards methods activating the potential of employees from various age ranges.

The main task of automotive catalytic converters is reducing the amount of harmful components of exhaust gases. Metallic catalytic converters are an alternative to standard ceramic catalytic converters. Metallic carriers are usually made from FeCrAl steel, which is covered by a layer of Precious Group Metals (PGMs) acting as a catalyst. There are many methods used for recovery of platinum from ceramic carriers in the world, but the issue of platinum and other metals recovery from metallic carriers is poorly described. The article presents results of preliminary experiments of metals biooxidation (Fe, Cr and Al) from spent catalytic converters with metallic carrier, using bacteria of the Acidithiobacillus genus.

Research on selective extraction of copper from solution after bioleaching grounded printed circuit boards (PCBs) using LIX 860N-IC were conducted. The effect of LIX 860N-IC concentration, phase ratio and influence of initial pH value of aqueous phase on the extraction of copper and iron was examined. It was found that the extraction rate of copper increases with the LIX 860N-IC concentration. Best results of Cu extraction (98 %) were achieved with extractant concentration of 5 % and pH 1.9. Higher pH value of aqueous phase (pH=2.4) is conducive to the simultaneous effect of Fe co-extraction.

Exhaust gases which are introduced into the atmosphere contain impurities such as carbon monoxide, unburned hydrocarbons and nitrogen oxide. Auto catalysts enable air pollution from these exhaust gases to be reduced considerably. Typical auto catalytic converters consist of the carrier (ceramic or metallic) and the catalytic system. Platinum group metals (PGM) are responsible for the catalytic function. All spent auto catalysts should be purchased and processed in order to recover the precious metals from them. This article presents the results of coupled analyses of electromagnetic and flow field calculations. The aim of this research was to design a device for extracting precious metals from used auto catalytic converters. Calculations were made to determine the velocity field distribution of a liquid metal, the movement of which was forced by the electromagnetic field. Computational experiments were conducted to obtain the relationships between the metal velocity distribution, the inductor supply and geometrical parameters in order to improve the construction of the presented device. The calculation shows that viscosity and friction has a greater influence on velocity distribution than forces distribution.

The alloys based on intermetallic phases involving Al belong to a new group of heat-resistant materials. Their physico-chemical and mechanical properties allow to apply them in the operating conditions in corrosive environment and elevated temperature. Research conducted for many years has shown that these materials can work at temperature up to 1100°C without degradation of their occurrence in the environment containing oxygen and sulphur. Heat resistance of these materials is provided by forming the Al2O3 passive layer on the surface. This layer is a protective barrier, which hinders the oxygen diffusion into the surface. This paper presents the morphology of passive Al2O3 layer depending on the temperature of its formation. The study allows to define the surface condition for corrosion products carried out using scanning electron microscopy together with EDS X-ray microanalysis.

Samochodowe konwertory katalityczne mają ograniczony czas życia, po czym katalizator ten należy wymienić lub poddać regeneracji. Zużyte katalizatory zawierają niewielkie ilości metali szlachetnych, a możliwość odzysku tych metali jest istotna ze względów ekonomicznych i ekologicznych. Równie atrakcyjne źródło metali szlachetnych stanowi wycofany sprzęt elektroniczny. Metale szlachetne w płytkach elektronicznych są zlokalizowane głównie w obwodach drukowanych układów scalonych, które są najbardziej zróżnicowane pod względem składu. Niejednorodność materiałowa tych elementów powoduje, że nie ma uniwersalnego sposobu przetwarzania tego rodzaju złomu. W artykule zwrócono uwagę na metody pirometalurgiczne i hydrometalurgiczne stosowane na świecie do odzysku metali szlachetnych ze zużytych katalizatorów samochodowych oraz od- padów elektronicznych. Przedstawiono wyniki badań próby wspólnego przetopu odpadów elektronicznych z odpadami zużytych katalizatorów samochodowych. Odpady elektroniczne w postaci drukowanych płytek obwodowych zostały wykorzystane jako nośnik i główne źródło miedzi, metalu pełniącego rolę metalu zbieracza platynowców, obecnych w katalizatorach. Otrzymano stop Cu-Fe-Au-Pt odzyskując w ten sposób platynę na poziomie około 78%.

The lifetime of a catalytic converters is limited. Today’s environmental regulations require that used converters should be properly recycled as a valuable source of precious metals, Al2O3 and steel scrap. The precious metals used in the devices perform catalytic functions. They are suspended in a ceramic or metal carrier. This paper deals with the recovery of precious metals from automotive converters using a metal-collector method. In order to speed up the washout of the precious metals from the capillary structure of the converter, the movement of the liquid metal-collector was forced by the electromagnetic field. The research was aimed at improving the effective velocity of the liquid metal flow through the carrier by means of a device with a double windings. Various ways of power supply were considered. The calculation experiment was performed as a weakly coupled analysis of the electromagnetic field and flow field.

The paper presents results of the research which aim was to compare the corrosion resistance of alloys based on intermetallic phase after Fe40Al5CrTiB crystallization and after forming the steel corrosion resistant X12CrCoNi2120 species. The tests were performed for steel at temperature of 700°C Fe40Al5CrTiB and for alloy at 1100°C and 9% O2 0.2% HCl + SO2+ 0.08 N2 environment. In the research the changes of weight after corrosion tests, observations of the surface, specified chemical and phase composition of corrosion products were made. The obtained results of the study showed a very good corrosion resistance of Fe40Al5CrTiB alloys in high temperature and environments containing oxygen, sulfur and chlorine as compared to the corrosion resistance of the steel grade X12CrCoNi2120. Results of the research conducted in this scope are the basis for further research.

At present, every launched car must be equipped with a catalytic converter, in which the precious metals such as platinum, palladium and rhodium play catalytic role. Catalytic converters have a limited life time, therefore they have to be replaced and become a valuable source of platinum group metals (PGM). Currently in the world, used auto catalytic converters are processed in pyrometallurgical or hydrometallurgical way. However, the first step of such treatment should be a chemical analysis. In the paper catalytic carriers were analysed taking into account the level of platinum. Scanning electron microscope was used. The analysis concentrated on testing samples coming from different catalytic carriers. The structure of tested samples, chemical analysis and X-ray energy spectra (EDS) where presented as well as the discussion of obtained results and possible methods of platinum recovery.

Today more and more cars are produced every year. All of them have to be equipped with catalytic converters, the main role of which is to obtain substances harmless to the environment instead of exhausted gases. Catalytic converters contain platinum group metals (PGM) especially platinum, palladium and rhodium. The price of these metals and their increasing demand are the reasons why today it is necessary to recycle used auto catalytic converters. There are many available methods of recovering PGM metals from them, especially platinum. These methods used mainly hydrometallurgical processes; however pyrometallurgical ones become more and more popular. The article presents results of the research mainly concerning pyrometallurgical processes. Two groups of research were carried out. In the first one different metals such as lead, magnesium and copper were used as a metal collector. During the tests, platinum went to those metals forming an alloy. In other research metal vapours were blown through catalytic converter carrier (grinded or whole). In the tests metals such as calcium, magnesium, cadmium and zinc were applied. As a result white or grey powder (metal plus platinum) was obtained. The tables present results of the research. Processing parameters and conclusions are also shown. To compare efficiency of pyrometallurgical and hydrometallurgical methods catalytic converter carrier and samples of copper with platinum obtained from pyrometallurgical method were solved in aqua regia, mixture of aqua regia and fluoric acid.

This paper presents possibility of removing platinum from the used catalytic converters applying copper as a metal collector in pyrometallurgical methods. The catalytic converter carrier was grinded and melted with copper. During the research obtained Cu-Pt alloy was casted as an anode. Such anode was electrically refined in order to recover platinum. Obtained results were discussed.

This paper presents the model for the washing-out process of precious metals from spent catalysts by the use of molten lead in which the metal flow is caused by the rotating electromagnetic field and the Lorentz force. The model includes the coupling of the electromagnetic field with the hydrodynamic field, the flow of metal through anisotropic and porous structure of the catalyst, and the movement of the phase boundary (air-metal) during infiltration of the catalyst carrier by the molten metal. The developed model enabled analysis of the impact of spacing between the catalysts and the supply current on the degree of catalyst infiltration by the molten metal. The results of calculations carried out on the basis of the model were verified experimentally.