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EN
Non-sulfide lead flotation tailings draw attention in terms of their valuable contents. Dissolution studies have been carried out with strong inorganic acids, especially in ore form, but these acids have been unfavorable in removal in the context of metal recovery processes. Organic acids, on the other hand, are notable for their environmentally friendly properties and selective metal recovery opportunities. In this study, the effects of acetic acid on metal recovery from oxidized waste were investigated with different experimental parameters at a laboratory scale. Optimal conditions were determined depending on the increase in acetic acid concentration. At 0.75-1.0 M acid concentrations, 49-55% Pb and 49-54% Zn recovery efficiencies were obtained with grades of 7.0-7.2% and 19.5-19.7%, respectively. The recovery of Pb/Zn by the leaching process with acetic acid and the selective nonrecovery of iron were also observed through characterization studies. With the Rietveld XRD method, an increase in iron minerals such as goethite and a decrease in smithsonite-hydrozincite minerals were determined. These changes were seen as a decrease in the contents of these minerals in SEM/EDX analysis and as a decrease in smithsonite mineral bond structures in the FT-IR analysis. This study showed that acetic acid has many advantages in the utilization of zinc-lead-containing oxide flotation tailings, which have high economic value, such as selective metal recovery, easy biodegradability, environmental friendliness, and non-corrosiveness.
EN
The manuscript explores the feasibility of recovering zinc and iron from waste galvanic sludge generated during galvanic plating processes. Galvanic sludge, characterized by elevated concentrations of heavy metals, represents a suitable candidate for hydrometallurgical recycling. The primary objective of the experimental and practical phases was to extract zinc and iron through the leaching of galvanic sludge. Leaching procedures were conducted using sulfuric acid at varying temperatures and time durations, augmented by the introduction of oxidizing agents such as hydrogen peroxide or ozone. Subsequent separation of the leach and filtrate was achieved through filtration. The leachate underwent additional processing involving the precipitation of iron and other metals, employing diverse agents. Following further filtration, electrolysis was employed to attain pure zinc on the cathode, utilizing an electrical voltage of approximately 3 V. Comprehensive chemical analyses were conducted on all intermediate products, including the leachate, leach liquor, filtrate, solid precipitate, and the separated metal on the cathode. The outcomes of these analyses are meticulously presented in tables and graphs.
EN
Trace elements are essential for the maintenance of the homeostasis of the body, and condition the proper functioning of the human organism. Micronutrients influence a number of metabolic processes in the dermis and epidermis. An excess or deficiency of trace elements may represent a potential threat to human health with implications for skin condition. This study reviews the literature on the effects of copper, zinc and selenium on skin condition.
EN
The Cerattepe (Artvin) mine contains volcanogenic massive sulfide (VMS) deposits in northeastern Turkey. This is a kuroko type deposit located in Late Cretaceous volcanic, intrusive and sedimentary rocks, and has a structure with dense alteration stages. In this study, batch flotation tests were carried out to determine the flotation behavior of a new sample (mix ore), that was the combination of two different ores with different flotation behaviors. The mixed ore contains 2.18% Cu, 1.46% Zn, (Cu/Zn ratio 1.49) 38.35% Fe, and 41.6% S content. An efficient separation of copper minerals from zinc minerals using the conventional selective flotation method could not be achieved due to complex mineralogy and very low liberation degree. Therefore, sequential selective flotation resulted in poor Cu recovery. The effects of flotation parameters such as collector type, collector amount, particle size, and pH conditions, were investigated to obtain a bulk copper-zinc concentrate. The best results were obtained using thionocarbamate (Aero 3894) and dithiophosphine (Aerophine 3418A) collector reagents at d80=40 μm particle size. Under optimal conditions (grain size, d80=40 μm, pH=11, amount of collector reagent 60 g/t (Aero 3894), frother (MIBC)=50 g/t, solid ratio=32%, flotation time=8 min.), a bulk copper-zinc concentrate containing 13% Cu and 9.5% Zn was obtained with a copper yield of 84.4% and a zinc yield of 88.9%. The concentrate mass pull was 13%. After rougher and two-stage scavenger flotation, a concentrate (rougher concentrate + scavenger products) was obtained with a mass pull of 22%. Copper and zinc recoveries of this concentrate were 91.8% and 92.5%, respectively.
5
Content available Synthesis and solubility of hopeite Zn3(PO4)2·4H2O
EN
Minerals from the phosphate groups are used in environmental engineering as thermodynamically stable vehicles for heavy metals such as zinc. The hopeite Zn3(PO4)2·4H2O was synthesized and characterized by X-ray diffraction and scanning electron microscopy. The solubility of the hopeite was measured at 25°C. The average solubility product, log Ksp, for the reaction Zn3(PO4)2·4H2O ⇔ 3Zn2+ + 2PO4 3− + 4H2O at 25°C is –35.72 ± 0.03. The free energy of formation, ΔG°f ,298, calculated from this measured solubility product is –3597.4 ± 1.0 kJ mol−1. The immobilization of zinc in the hopeite structure offers the possibility of developing an effective method for removing Zn from wastewater, water and soils.
EN
Among a number of climate-related factors, moisture has the greatest impact on crop productivity. In recent years, certain changes have been observed under conditions of the Forest-Steppe of Ukraine with regard to precipitation – from low to in some cases – abnormally high, which requires the study of their impact on the yield and safety of cereal grain for its forecasted production. The article examined the effect of a high level of soil moisture (256.2–272.5 mm) and a low level (47.4–52.3 mm) during the growing season (germination→earing) of spring barley grain on the accumulation of heavy metals in it and its productivity under the conditions of gray forest soils of the Right Bank Forest Steppe of Ukraine. Spring barley varieties Helios and Caesar were selected for the research. A decrease in the accumulation coefficient at a high level of soil moisture (256.6–272.5 mm) in spring barley grain Pb from 8.3% to 11.3%, Cd – from 35.0% to 35.5%, Zn was established – by 15% and Cu – from 11.2% to 16.6% compared to the low level of soil moisture (47.1 mm – 53.3 mm). At the same time, it was found that with a high level of soil moisture, there is a decrease in the yield of Helios and Caesar spring barley by 18.0% and 14.1%, respectively.
EN
In this study, three experiments using the fixed anode technique and approached anode technique were carried out. The first experiment (EK-1) used distilled water as leaching solution (purging solution) at the anode and cathode chamber under voltage gradient was equal to 1.5 V/cm. In the second and third experiments, a solution enhanced with 1M acetic acid (AA) was used as catholic solution. The results indicate that residual concentration of Zn+2 decreases, beginning with an initial value of 850 mg/kg in all portions of soil sample EK-1, EK-2, in addition to EK-3. It seems that the residual concentration of EK-3 (approached anode technique) was lower than that of EK-1 and EK-2 in identical portions.
EN
The subject of this study was to determine the effectiveness of Aspergillus niger (Pezinok) and Neosartorya fischeri strains in bioleaching and bioaccumulation of metals from mining waste from the Hodruša tailings pond. The waste used in the work contained 0.10 mm fractions weighing 1 and 2 g from different depths of the soil matrix, samples A: 10–20 cm, samples B: 20–30 cm. We focused on the elements copper, lead and zinc with the content of individual elements (mg/kg) copper – in samples A 487 mg/kg, in samples B 115 mg/kg. Lead – samples A 1208 mg/kg, samples B 582 mg/kg. Zinc – samples A 6970 mg/kg, samples B 6808 mg/kg. We confirmed the effectiveness of the Aspergillus niger strain in this process due to the production of organic acids (citric acid, oxalic acid, acetic acid). In the experimental part, we found that the most effective strain in determining the efficiency of extraction and concentration of metals in the solution after bioleaching was the Aspergillus niger strain. The Neosartorya fischeri strain appears to be most effective in accumulating metals in solution and accumulating metals in biomass. We can justify this phenomenon due to the different properties of the cell walls of individual fungal strains and it is necessary to keep these differences in mind when comparing biosorption properties
PL
Przedmiotem niniejszego badania było określenie skuteczności szczepów Aspergillus niger (Pezinok) i Neosartorya fischeri w bioługowaniu i bioakumulacji metali z odpadów górniczych ze stawu osadowego Hodruša. Odpady wykorzystane w pracy zawierały frakcje 0,10 mm o masie 1 i 2 g z różnych głębokości matrycy glebowej, próbki A: 10–20 cm, próbki B: 20–30 cm. Skupiliśmy się na pierwiastkach miedzi, ołowiu i cynku z zawartością poszczególnych pierwiastków (mg/kg) miedź – w próbkach A 487 mg/kg, w próbkach B 115 mg/kg. Ołów – próbki A 1208 mg/kg, próbki B 582 mg/kg. Cynk – próbki A 6970 mg/kg, próbki B 6808 mg/kg. Potwierdziliśmy skuteczność szczepu Aspergillus niger w tym procesie ze względu na produkcję kwasów organicznych (kwas cytrynowy, kwas szczawiowy, kwas octowy). W części eksperymentalnej stwierdziliśmy, że najskuteczniejszym szczepem w określaniu wydajności ekstrakcji i stężenia metali w roztworze po bioługowaniu był szczep Aspergillus niger. Szczep Neosartorya fischeri wydaje się być najbardziej efektywny w akumulacji metali w roztworze i akumulacji metali w biomasie. Zjawisko to można uzasadnić różnymi właściwościami ścian komórkowych poszczególnych szczepów grzybów i należy pamiętać o tych różnicach przy porównywaniu właściwości biosorpcyjnych.
EN
Zinc is an essential microelement that is required for the proper growth and development of crops, and its content in the soil varies. Due to the physiological functions it performs in living organisms, zinc is considered an essential element in the nutrition of plants and animals. The total forms of trace elements do not fully reflect the possibilities of their absorption. They provide only approximate ranges of the soil’s abundance in a given ingredient. Plants can obtain microelements only from bioavailable forms.The content of available forms of elements in soils is one of the important determinants of plant yield. Zinc deficiency is a serious problem in agricultural soils around the world because it results in reduced crop yields. The aim of the study was to assess the content of total and available forms of zinc in the surface horizons of arable Luvisols in the Pałuki region, that has been intensively used for agriculture. Basic physical and chemical soil properties were determined using methods commonly applied by soil science laboratories. The content of total zinc forms was determined using the Crock and Severson method. Forms bioavailable to plants were identified using the Lindsay and Norvell method. The content of both forms of zinc was determined by atomic adsorption spectroscopy (AAS). In the analysed samples of arable land, low contents of total and available forms of zinc were recorded. The correlation analysis that was carried out confirmed that the content of these forms in the soil is significantly influenced by reaction. Due to the low levels of zinc forms found in the studied agricultural soils, It is necessary to monitor the amounts of this trace element.
PL
Cynk jest mikroelementem niezbędnym do prawidłowego wzrostu i rozwoju roślin uprawnych, a jego zawartość w glebie jest zróżnicowana. Ze względu na funkcje fizjologiczne, jakie pełni w organizmach żywych, cynk uznawany jest za pierwiastek niezbędny w żywieniu roślin i zwierząt. Formy całkowite pierwiastków śladowych nie odzwierciedlają w pełni możliwości ich wchłaniania. Podają jedynie przybliżone zakresy zasobności gleby w dany składnik. Rośliny mogą pozyskiwać mikroelementy jedynie z form biodostępnych. Zawartość przyswajalnych form pierwiastków w glebie jest jednym z ważnych czynników warunkujących plonowanie roślin. Niedobór cynku jest poważnym problemem w glebach rolniczych na całym świecie, ponieważ powoduje zmniejszenie plonów. Celem badań była ocena zawartości form całkowitych i przyswajalnych cynku w poziomach powierzchniowych uprawnych gleb płowych regionu Pałuk, który od dziesięcioleci jest intensywnie użytkowany rolniczo. Podstawowe właściwości fizyczne i chemiczne gleby określono metodami powszechnie stosowanymi w laboratoriach gleboznawczych. Zawartość form cynku całkowitego oznaczono metodą Crocka i Seversona, a formy biodostępne dla roślin metodą Lindsaya i Norvella. Zawartość obu form cynku oznaczono metodą atomowej spektroskopii adsorpcyjnej (AAS). W analizowanych próbach gruntów ornych stwierdzono niską zawartość form całkowitych i przyswajalnych cynku. Przeprowadzona analiza korelacji potwierdziła, że na zawartość tych form w glebie istotny wpływ ma odczyn. Ze względu na niską zawartość form cynku w badanych glebach rolniczych, konieczne jest monitorowanie ilości tego mikroelementu.
EN
The research presented in this paper concerns the influence of the rate of plastic deformation generated directly in the processes of severe plastic deformations on the microstructure and properties of three metals: copper, iron and zinc. The equal channel angular pressing (ECAP) method was used, and it was performed at a low plastic deformation rate of ∼ 0.04 s−1. The high plastic strain rate was obtained using the hydrostatic extrusion (HE) method with the deformation rate at the level of ∼ 170 s−1. For all three tested materials different characteristic effects were demonstrated at the applied deformation rates. The smallest differences in the mechanical properties were observed in copper, despite the dynamic recrystallization processes that occurred in the HE process. In Armco iron samples, dynamic recovery processes in the range of high plastic deformation rates resulted in lower mechanical properties. The most significant effects were obtained for pure zinc, where, regardless of the method used, the microstructure was clearly transformed into bimodal after the ECAP process, and homogenized and refined after the HE process. After the HE process, the material was transformed from a brittle state to a plastic state and the highest mechanical properties were obtained.
EN
This paper deals with the numerical simulation of a pilot-scale axial cyclone separator. The main purpose of this paper is to develop a numerical model that is able to foresee the cyclone separator cut-off point. This is crucial in blast furnace gas installation to capture large particles containing carbon and iron, while allowing smaller particles such as zinc and lead to pass through. The cut-off point must be designed to give a sufficiently high zinc and lead content in the sludge created after the second cleaning stage. This allows the sludge to become a commercial product. To design this cut-off point, an investigation of the influence of inlet gas velocity, temperature, and the angle of guiding vanes at the inlet was done. The developed CFD model was validated against experimental data on the fractional efficiency of the cyclone separator. The results were in good agreement with the experimental data for all parameters tested. The behavior of the particles inside the cyclone was also physically correct.
EN
In recent years, the production of galvanized sheet steels with organic coatings applied to its surfaces has considerably expanded. Phosphating of the zinc surfaces raises its roughness and surface tension, providing high adhesion of subsequent organic coatings and respectively, significant increasing of their protective properties. The paper presents the results obtained in the investigation of combined anti-corrosion coatings, including formation of phosphate films on galvanized steel surfaces followed by the application of three types of paint and varnish coatings. The indicators characterizing the phosphating preparation (density, pH, conductivity, acid capacity) as well as the thickness of the coatings were measured. The chemical composition of the phosphate films, their morphology and topography were determined by means of EDX and SEM, respectively. The adhesion, elasticity and impact toughness of the organic coatings, with and without phosphating treatment of the zinc surfaces were measured. The corrosion resistance of the combined coatings in a model sodium chloride solution was also determined.
EN
In this study, a research was conducted to recover metallic zinc and pig iron and to improve the purity and the recovery rate through a reduction process for zinc and iron in the byproducts that are generated after steelmaking dust treatment. As the result of the calcination, it was confirmed that Cl (6.06%) and K (3.37%) decreased to Cl (2.75%) and K (0.22%), respectively. For the zinc powder that was recovered with reaction temperature of 1100°C, reaction time of 4 hours, and argon gas of 1L/min as the optimal conditions. The measurement for the purity of zinc was 99.8% and the recovery rate was 92.14%. The melt reduction for recovering pig iron from the residue was reacted under reaction temperature of 1600°C, flux composition (CaO:SiO2) of 1:1, and reducing agent infusion ratio (residue: C) of 14:1, and the pig iron was measured to have a purity of 87.7% and a recovery rate of 91.81%.
14
Content available remote Rola cynku w ochronie przeciwkorozyjnej stali - przegląd zastosowań
PL
Metaliczny cynk, w różnych postaciach, jest nadal masowo i z doskonałymi rezultatami wykorzystywany w wielu technikach ochrony przed korozją konstrukcji i wyrobów stalowych eksploatowanych w różnych warunkach – w atmosferze, wodzie i ziemi. Niniejsze opracowanie ma na celu wskazanie różnych sposobów wykorzystania właściwości tego metalu zarówno w uzyskiwaniu efektów barierowych w powłokach, jak i polaryzacji elektrochemicznej w systemach ochrony katodowej.
EN
Metallic zinc, in various forms, is still massively and with excellent results used in a number of corrosion protection techniques for steel structures and steel products operated in various conditions: in the atmosphere, in water and in the underground. This study aims to indicate different ways of using the properties of this metal both in obtaining barrier effects in coatings and in electrochemical polarization in cathodic protection systems.
15
Content available Zinc and Magnesium vs COVID-19
EN
Zinc and magnesium are among the most important elements for the human body. A deficiency or excess of either of them may pose a potential threat to the homeostatic mechanisms of the body. Both elements condition the proper functioning of the immune system. Zinc and magnesium deficiency significantly reduces the body's immunity, facilitating infection with various pathogens, including SARS-COV-2 infection. In this paper, we reviewed the literature on the impact of zinc and magnesium deficiencies on the incidence and course of COVID-19.
PL
Cynk i magnez to jedne z ważniejszych pierwiastków dla organizmu człowieka. Niedobór lub nadmiar któregoś z nich może stanowić potencjalne zagrożenie dla mechanizmów homeostazy ustroju. Pierwiastki te warunkują prawidłowe funkcjonowanie układu immunologicznego. Niedobór cynku i magnezu istotnie zmniejsza odporność organizmu ułatwiając infekcje różnymi patogenami, w tym zakażenia SARS-COV-2. W pracy dokonano przeglądu piśmiennictwa obejmującego zagadnienia wpływu niedoborów cynku i magnezu na zachorowanie i przebieg COVID-19.
PL
W artykule opisano systemy antykorozyjne z powłoką gruntującą zawierającą wypełniacz cynkowy, których użycie rośnie z roku na rok ze względu na dużą trwałość. Ich wykorzystanie nie pozostaje jednak bez wpływu na środowisko naturalne. Jednym ze sposobów ograniczenia zawartości cynku jest stosowanie nowych cynkowych powłok gruntujących opracowanych w projekcie ZINCPOWER (CORNET).
EN
The article describes anticorrosion systems containing zinc primers, which are used increasingly year by year due to their durability. However they are not without consequences for the environment. One of the methods of reducing the content of zinc is the use of new zinc primer coats which were developed in the ZINCPOWER (CORNET) project.
EN
Multi-million tons of sludge produced as a result of wet dedusting of blast furnace and converter gases have been deposited in landfills across the country. These materials are also created on an ongoing basis. Due to the high iron content, their potential as a ferrous raw material is significant. Unfortunately, in addition to components which are desirable from the point of view of metallurgical processes such as Fe, C and CO, they also contain many harmful elements such as Zn, Pb, Na and K. The article describes the sources and form of Zn found in post-production waste of steelworks and the methods of removing zinc from ferrous waste materials. The optimal conditions for zinc removal during the sintering process of galvanised ferrous materials were identified using thermochemical calculations carried out with the FactSage computer program.
PL
Na terenie kraju na składowiskach zdeponowano wielomilionowe ilości ton szlamów powstałych w wyniku mokrego odpylania gazów wielkopiecowych i konwertorowych. Materiały te powstają także na bieżąco. Z uwagi na dużą zawartość żelaza ich potencjał jako surowca żelazonośnego jest znaczący. Niestety oprócz pożądanych składników z punktu widzenia procesów metalurgicznych Fe, C, CO, zawierają one także wiele pierwiastków szkodliwych takich jak: Zn, Pb, Na, K. W artykule opisano źródła pochodzenia i postać Zn występującego w odpadach poprodukcyjnych hut oraz metody usuwania cynku z odpadowych materiałów żelazonośnych. Dokonano identyfikacji optymalnych warunków usuwania cynku w czasie procesu spiekania zacynkowanych materiałów żelazonośnych, dokonując obliczeń termochemicznych przy użyciu programu komputerowego FactSage.
EN
Given the imminent deterioration of environmental quality, the accumulation of heavy metals in agricultural soil is one of the main concerns worldwide. Therefore, this research aimed to evaluate the adsorption potential of mercury and zinc by Sphagneticola trilobata. After 60 days, the distribution of heavy metals in the roots and the leaves of the plants was determined. As a result, the plant adsorbed mercury between 43.49 and 59.22%, and zinc between 32.68 and 64.37%. According to the bioconcentration and translocation factors of Sphagneticola trilobata obtained in the present work, the phytostabilizing capacity of mercury and zinc is like Eichhornia crassipes and Sorghum bicolor.
EN
The enzymatic pool of the soil is formed over a long period of time under the influence of many natural factors. Therefore, the information on the lability of soil enzymes under the influence of the main abiotic factors is necessary for the diagnosis of the anthropogenic influence on ecosystems. The aim of the study was to determine the variability of the activity of catalase, invertase, and urease in sod-podzolic and grey forest soils in response to the main abiotic factors and model pollution. The studied areas belonged to the subzones of middle and southern taiga and mixed forests, the average annual temperature ranged from 2.9 to 6.6 ℃, and the рНKCl level of extracts from soils was in the range of 4.2–5.6. It was shown that the activity of exozymes in the soil of southern taiga and mixed forests depends most of all on the average annual temperature and pH level. No relationship between the enzyme activity and soil organic carbon was found. Artificial soil salinity led to an increase in the activity of invertase and urease. Soil contamination with zinc (25.5 and 255.0 mg/kg of dry soil) suppressed only the invertase activity. Thus, the influence of natural abiotic factors on the activity of soil enzymes was more often found than the chemical load.
20
Content available remote Znaczenie cynku w produkcji cementu portlandzkiego
PL
W doświadczeniach laboratoryjnych stwierdzono nieoczekiwany wpływ dodatku cynku, który przyspieszył proces wiązania cementu portlandzkiego. Ten nietypowy wpływ cynku został spowodowany przez dodatek anhydrytu II, jako regulatora wiązania cementu, przez jego producenta. Anhydryt II rozpuszcza się bardzo powoli i stężenie jonów siarczanowych w zaczynie hydratyzującego cementu było bardzo małe. Natomiast cynk rozpuścił się bardzo szybko, a powstający wodorotlenek strącał się na powierzchni kryształów C3A, utrudniając powstawanie ciągłej warstwy ettringitu. Ettringit powstawał w tych warunkach w wolnych przestrzeniach w roztworze, łącząc ziarna cementu, powodując szybkie wiązanie „ettringitowe”. Natomiast, kryształy alitu pozostają ciągle pokryte bezpostaciową warstewką Zn(OH)2, i w tych warunkach okres indukcji reakcji z wodą tej fazy, pozostaje bez zmian. Przedłużenie tego okresu rośnie ze zwiększeniem dodatku cynku.
EN
In laboratory experiments, we found the unexpected influence of zinc addition, which was the acceleration of the Portland cement setting. This untypical cement behaviour was caused by the addition of anhydrite II as the setting time regulator, by its producer. Anhydrite II dissolves very slowly and the sulphate ions concentration in the paste of the hydrating cement, was very low. However, zinc was soluted very quickly and its hydroxide precipitated on the surface of C3A crystals, limiting the formation of the continuous ettringite layer. Thus, ettringite is formed in the free areas in the solution, linking the cement grains, with the formation of the quick “ettringite” setting. Ettringite precipitated in the free areas within the solution, binds to the cement grains and causes the ‘quick’ setting of ettringite. However, the alite crystals remain continuously covered by the amorphous layer of Zn(OH)2, and under this condition the induction period with water reaction of this phase remains hang-up. The elongation of this period is increasing with the increase in the addition of zinc.
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