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1

Optimization of tungsten inert gas welding process parameters for joining austenitic stainless steel and copper using the Taguchi method

Bensaid Nabil, Benlamnouar Mohamed Farid, Laksir Yazid Laib Dit, Saadi Tahar, Badji Riad

Advances in Science and Technology. Research Journal

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2025

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Vol. 19, no. 1

209--219

EN

This study aims to optimize the Tungsten Inert Gas (TIG) welding parameters for joining AISI 316L stainless steel and Cu-ETP copper using 309L stainless steel filler rods. Welding dissimilar materials is challenging due to their significant differences in thermal and mechanical properties. The high thermal conductivity of Cu-ETP copper leads to rapid heat dissipation, causing uneven heat distribution at the weld interface. To address this issue, the research team applied a 1 mm offset of the welding torch toward the copper side to balance the heat input. They employed statistical analyses using ANOVA and the Taguchi method to determine the optimal process parameters. The results showed that the optimal welding current, welding speed, and gas flow for achieving high tensile strength (Rm) are 90 A, 0.5 mm/s, and 12 l/min, respectively. Among these, welding speed emerged as the most significant factor, influencing 48.74% of the weld characteristics. Mechanical testing confirmed that these parameters produced high-quality welds. Metallurgical analysis revealed minimal diffusion between the materials, preserving their distinct properties while minimizing the formation of undesirable intermetallic phases. These results highlight the effectiveness of TIG welding in creating robust joints between AISI 316L stainless steel and Cu-ETP copper for applications requiring a combination of both materials' properties.

2

Analysis of Tribological Wear of Metallic Membranes After the Hydrogenation Process

Rutkowska-Gorczyca Małgorzata, Winnicki Marcin, Kowalewski Piotr

Tribologia

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2024

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nr 2

95--104

EN

The paper presents the results of tribological tests of copper material subjected to the cyclic hydrogenation process. Tribological tests during friction in reciprocating motion, in contact with a ceramic ball. The measurement was performed for different numbers of hydrogenation cycles, different surface roughness and different times after the machining process. The test material consisted of metallic membranes made of dendritic copper particles using the additive method of low-pressure cold gas spraying (LPCS). The hydrogen charging process was carried out using a BioLogis SP50ze potentiostat/galvanostat. The current waveforms were carried out in an electrolyte with a concentration of 0.5 M H2SO4 . Voltammetry (CV measurement) was performed in a three-electrode system, where the metallic membrane was the working electrode. The hydrogen charging process included two ranges: 25 cycles (1 hour) and 50 cycles (2 hours). The system was cyclically loaded with current between a potential of -0.200 V and -1.4 V, with a scanning rate of 20 mV/s. The tests carried out allowed for obtaining the values of the friction coefficient and the wear depth. For materials with a developed surface (high roughness), a decrease in the value of the friction coefficient and the depth of the wear trace was observed with an increase in the number of hydrogenation cycles. This indicates an increase in the amount of hydrogen in the rubbing surface by expanding the surface. In the case of polished samples, the best results were obtained with 25 hydrogenation cycles.

PL

W pracy przedstawiono wyniki badań tribologicznych materiału miedzianego poddanego procesowi cyklicznego nawodorowywania. Badania tribologiczne podczas tarcia w ruchu posuwisto-zwrotnym w styku z kulką ceramiczną wykonano dla różnych ilości cykli nawodorowywania, różnej chropowatości powierzchni i w różnym czasie od procesu obróbkowego. Materiał do badań stanowiły membrany metaliczne wykonane z dendrytycznych cząstek miedzi metodą przyrostową niskociśnieniowego natrysku zimnym gazem (LPCS). Proces ładowania wodorem przeprowadzono z zastosowaniem potencjostatu/galwanostatu BioLogis SP50ze. Przebiegi prądowe prowadzono w elektrolicie o stężeniu 0,5 M H2SO4. Woltamperometrię (pomiar CV) przeprowadzono w układzie trójelektrodowym, gdzie membrana metaliczna stanowiła elektrodę roboczą. Proces ładowania wodorem obejmował dwa zakresy 25 cykle (1 h) oraz 50 cykli (2 h). Układ był cyklicznie prądowo obciążany między potencjałem o wartości -0,200 V a -1,4 V, z szybkością skanowania 20 mV/s. Przeprowadzone badania pozwoliły na uzyskanie wartości współczynnika tarcia oraz głębokości zużycia. Dla materiałów o rozwiniętej powierzchni (duża chropowatość) zauważono zmniejszanie wartości współczynnika tarcia oraz głębokości śladu zużycia wraz ze zwiększaniem ilości cykli nawodorowywania. Wskazuje to zwiększenie ilości wodoru w powierzchni trącej poprzez rozwinięcie powierzchni. W przypadku próbek wypolerowanych najlepsze wyniki uzyskano przy 25 cyklach nawodorowywania.

3

Study on laser welding of a copper material and stainless steel

Wang Renping

Przemysł Chemiczny

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2024

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T. 103, nr 9

963--967

EN

A com. fiber laser was used to weld Cu and stainless steel plates. The laser power was 2.2 kW, the welding speed 2.5 mm/s, the spot diam. about 0.5 mm, and the wire feeding speed 2-3.5 mm/s. Ar gas flow rate was 10 L/min. The weld produced was smooth and defect-free, the grain distribution was uniform and the mech. properties of the joint were high. The av. tensile strength of the welded joints was 984 MPa, and the av. yield strength of the joints was 351.4 MPa. The superior ity and potential of laser welding in dissimilar metal welding was evidenced.

PL

Do spawania płyt z miedzi i stali nierdzewnej użyto komercyjnego lasera światłowodowego. Moc lasera wynosiła 2,2 kW, prędkość spawania 2,5 mm/s, średnica plamki ok. 0,5 mm, prędkość podawania drutu 2-3,5 mm/s, a natężenie przepływu argonu 10 L/min. Uzyskana spoina była gładka i wolna od wad, rozkład ziarna był równomierny. Spoina miała dobre właściwości mechaniczne. Średnia wytrzymałość na rozciąganie spoin spawanych wynosiła 984 MPa, a średnia granica plastyczności spoin to 351,4 MPa. Udowodniono potencjał spawania laserowego w spawaniu różnych metali.

4

Detachment and flow behaviour of anode slimes in high nickel copper electrorefining

Sahlman Mika, Aromaa Jari, Lundström Mari

Physicochemical Problems of Mineral Processing

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2024

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Vol. 60, iss. 2

art. no. 186194

EN

Most of the world’s copper is produced via copper electrorefining, where nickel is the most abundant impurity in the process. Previously it has been suggested that nickel affects the adhesion of anode slimes on the anode as well as the porosity of the slime layer that forms. This paper investigates the effects of nickel, oxygen, sulphuric acid and temperature on the detachment of anode slimes from the anode surface. The detachment of particles as a function of both anode and electrolyte composition was studied on laboratory scale using a camera connected to a Raspberry Pi, and particle detection and movement analysed using TrackPy. The results revealed four different slime detachment mechanisms: cloud formation, individual particle detachment, cluster detachment and avalanche. These were found to be dependent on the electrolyte (0, 10, 20, 30 g/dm3 Ni2+ & 100, 200 g/dm3 H2SO4), with increasing nickel concentration promoting cluster detachment and increasing sulphuric acid concentration favouring detachment of individual particles. Anode composition (0.05-0.44 wt% O and 0.07-0.64 wt% Ni) was shown to affect the flow direction of anode slimes, with increasing nickel leading to more upward-flowing slimes. Typical particle movement velocities were from -0.5 to 1.0 mm/s regardless of the electrolyte and anode composition, and regardless of the operating temperature (25 °C & 60 °C) for small particles (<0.5 mm). The results also support previous findings that increasing the nickel concentration of the electrolyte leads to a more porous anode slime layer on the anode.

5

Secondary arsenates from the Ľubietová-Svätodušná copper deposit in Slovakia

Solecka Urszula

Journal of Geotechnology and Energy

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2024

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Vol. 41, no. 4

35--42

EN

In the vicinity of Lubietová in the Banská Bystrica region in Slovakia, copper was mined in three deposits: Podlipa, Svätodušná, and Kolba. The study concerns the association of secondary arsenates of the Lubietová-Svätodušná copper deposit. The Lubietová-Svätodušná deposit contains a large number of secondary minerals, formed as a result of weathering in the hypergene zone. Among them, copper arsenates are the most important, due to the rare occurrence of some of them. Four secondary arsenates have been characterized: chalcophyllite, euchroite, olivenite and pharmacosiderite. The minerals were identified using X-ray diffraction (XRD), whereas observations under a scanning electron microscope (SEM) and chemical analysis (EDS) showed that some of them are heterogeneous, contain different substitutions, and show significant variability in the content of individual elements within single specimens.

6

Using Eucalyptus Peels as a Permeable Reactive Barrier for Treating Groundwater Contaminated with Copper Ions – A Simulation with COMSOL Software

Shno Mustafa Ali Muhammed, Al-Qaisi Atheer Zaki, Al Yousif Mustafa A., Alkadhim Nooruldeen

Journal of Ecological Engineering

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2024

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Vol. 25, nr 11

37--45

EN

This study investigated the use of eucalyptus peels as a permeable reactive barrier (PRB) for treating groundwater contaminated with copper ions. Activated carbon was produced from eucalyptus peels, and its adsorption capacity for copper removal was evaluated through laboratory experiments. COMSOL software was used to simulate the performance of the eucalyptus peel-based PRB in order to optimize the design as well as predict the efficiency and longevity of the barrier. Batch studies were conducted to evaluate how factors such as the initial concentration of the contaminant, pH level, contact time, amount of sorbent used, and agitation speed affected the results. The results show that the optimal values of these factors were a 50 ppm concentration, a pH of 6, an 80-minute contact time, a dosage of 2 mg per 100 ml, and a stirring speed of 250 rpm. These findings demonstrate that eucalyptus peels, being an agricultural waste product, can be effectively converted into activated carbon with a high adsorption capacity (equal to 91.5%) for copper ions. To analyze the data, researchers utilized COMSOL Multiphysics 3.5a software, which employs the finite element method to solve the equations that describe the one-dimensional (1D) movement of copper under equilibrium conditions. Compared to other organic and inorganic adsorbents commonly used in PRBs, eucalyptus peels showed promising results in terms of adsorption capacity and cost-effectiveness. This study contributes to the development of innovative and sustainable remediation strategies for groundwater contaminated with heavy metals like copper. The findings demonstrate the potential of eucalyptus peels as a viable alternative to traditional adsorbents used in PRBs, promoting the use of renewable materials in environmental management and indicating that the PRB significantly impedes the movement of the copper plume. Ultimately, the predictions from the COMSOL simulations were very close to the actual experimental results, with a root mean square error (RMSE) of less than 1%.

7

Ecological Risk Assessment of Heavy Metal Contamination in Water, Sediment, and Polychaeta (Neoleanira Tetragona) from Coastal Areas Affected by Aquaculture, Urban Rivers, and Ports in South Sumatra

Rozirwan, Az-Zahrah Shahnaz Ajeng Fatimah, Khotimah Nadila Nur, Nugroho Redho Yoga, Putri Wike Ayu Eka, Fauziyah, Melki, Agustriani Fitri, Siregar Yusni Ikhwan

Journal of Ecological Engineering

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2024

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Vol. 25, nr 1

303--319

EN

Industrial activities in coastal areas can produce pollutant substances that are detrimental to the ecological environment. This study aimed to assess the ecological risks of heavy metal pollution in water, sediments, and polychaeta (Neoleanira tetragona) affected by aquaculture, urban rivers, and ports. Water parameters such as temperature, DO, pH, and salinity were measured in situ at fifteen observation stations. Samples were taken at three locations around the aquaculture area, namely the Barong River, the Musi River Estuary as an urban river area, and Tanjung Api-api port in South Sumatra, Indonesia. Analysis of sediment grain size and substrate types using the method of Shepard’s triangle Heavy metal concentrations were measured by graphite furnace atomic absorption spectrometry. Then, the data were analyzed using one-way analysis of variance (ANOVA) and post-hoc Tukey statistical analysis. Ecological risk assessment uses the bioconcentration factor (BCF), index geoaccumulation (Igeo), contamination factor (Cf), and pollution load index (PLI). Based on the results, the concentration of heavy metal Pb in water was not detected until 0.625 mg/L, and Cu was not detected. Furthermore, Pb in sediments was 1.261–11.070 mg/kg, Cu was 0.193–19.300 mg/kg, Pb polychaeta was not detected until 0.0044 mg/kg, and Cu ranged from 0.0003–0.0014 mg/kg. Ecological risk assessment for BCF showed that the level of accumulation of polychaeta (N. tetragona) was categorized as an excluder (BCF < 1). Igeo and Cf indicate uncontaminated pollution levels (Igeo < 0) and low contamination (Cf < 1). Meanwhile, the Pollution Load Index is included in the nonpolluted category (PLI <0). Based on the results, the quality of the ecological environment affected by aquaculture, urban rivers, and ports is still classified as safe for ecological risk assessment; further studies are needed regarding the relationship between pollution levels and the physiological response of biota.

8

Pollution indicators of heavy metals in the sediments of the Lepenc River in Kosovo

Dreshaj Lecaj Elida, Haskaj Adelina, Paçarizi Musaj

Environment Protection Engineering

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2024

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Vol. 50, nr 3

77--87

EN

The sediments of the Lepenc River in Kosovo have been investigated, by using X-ray fluorescence (XRF) technique. The concentrations of such metals as As, Ca, Cr, Cu, Fe, K, Mn, Nb, Ni, Pb, Rb, Sr, Th, Ti, V, Y, Zn and Zr were analyzed in six different locations. The most of metals analyzed had median values higher than those in European steam sediment. Basic statistics, Pearson’s correlation and cluster analysis were performed to better explain the data of metal concentrations in the river sediments. Four groups of elements were identified by cluster analysis based on their geogenic or anthro-pogenic origin. The sediments were mostly contaminated with potentially toxic elements (As, Cr, Cu and Ni). The contamination factors (CF) for different metals and locations ranged from 1.8 to 5.33, and the pollution load index (PLI) from 2.42 to 3.09. Nickel and chromium contributed the most to sediment pollution, and their geoaccumulation indices (Igeo) in all locations were higher than 1. The most polluted sediment samples were in two locations, in the vicinity of a nickel mine and a cement factory.

9

Bioconcentration and Translocation of Heavy Metals in Mangrove Avicennia sp. and Rhizophora sp. in Diesel Powel Plant

Basri Siti Aras Ainun, Samawi Muhammad Farid, Fahruddin Fahruddin

Ecological Engineering & Environmental Technology

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2024

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Vol. 25, iss. 9

223--230

EN

Diesel power plants produce wastewater containing heavy metals. This study focused on analyzing the role of mangroves around the site. The results showed that Cu metal concentrations in sediments ranged from 10.01–17.76 mg/kg and Cr ranged from 13.06–20.34 mg/kg, and Cu and Cr metal concentrations in Avicennia sp. mangrove were 25.04–42.05 mg/kg; 11.78–28.21 mg/kg, respectively, and showed bioaccumulation and translocation abilities of Cu and Cr of 2.34–2.5 (BCF > 1) and 0.6–0.69 (TF < 1); 0.9–1.39 (BCF < 1) and 0.4–0.53 (TF < 1), while in mangrove Rhizophora sp., namely 13.51–29.24 mg/kg; 21.52–58.38 mg/kg, and showed bioaccumulation and translocation abilities of Cu and Cr, respectively, 1.35–1.64 (BCF > 1) and 0.61–0.74 (TF < 1); 1.65–2.87 (BCF > 1) and 0.62–0.84 (TF < 1). BCF > 1 indicates that mangroves are accumulators, and BCF < 1 is an excluder. TF value < 1 indicates that mangroves are phytostabilisers. This research can be a reference for diesel power plant companies to plant mangroves Avicennia sp. and Rhizophora sp. around the source of wastewater outlets. In addition to absorbing CO2 emissions in the environment, they can also absorb heavy metals derived from diesel processing.

10

Mechanical behaviour and failure mechanism of resistance spot welded aluminium and copper joint used in the lightweight structures

Fakhri Marwah Sabah, Al-Mukhtar Ahmed, Mahmood Ibtihal A.

Diagnostyka

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2024

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Vol. 25, No. 2

art. no. 2024207

EN

Recently, dissimilar metals have found applications in the process of resistance spot welding (RSW), particularly within the electric vehicle industry. Notably, copper and aluminum have gained significant importance in these sectors due to their advantageous characteristics for the industry requirements. The mechanical behavior of these materials is essential to maintaining structural integrity. The study aims to estimate the mechanical behavior of dissimilar RSW joints and optimize welding parameters for Cu-Al joints. Hence, understanding the joining processes in the electric vehicle industry to design reliable components. Combining different types of materials, such as T2-grade commercially pure copper sheets and aluminum AA1050 with the same thickness of 1 mm has been welded. The determination of optimal welding conditions takes into account material thicknesses and types. Through tensile-shear testing, welding parameters that yield maximal joint strength were identified. Using Minitab 19 software, the Taguchi method helped achieve optimized welding parameters. The hardness, fracture characteristics, and weld strength have been investigated. Hardness measurements were conducted across the nugget thickness and surface, offering insights into potential failure modes. The welding process involves the transition to a liquid state for the aluminum components, resulting in the formation of intermetallic compounds. Consequently, crack initiation was observed within the aluminum segments, leading to a plug-out fracture mechanism. In contrast, copper exhibits superior strength and hardness compared to aluminum, where increased hardness correlates with heightened strength. The discrepancy in hardness, especially the lower values observed on the aluminum side, caused fractures to appear within the heat affected zone (HAZ). Subsequently, this fracture propagated until pull-out failure was realized. The study revealed that dissimilar joining of Cu and Al resulted in an ultimate tensile stress of 26 MPa, while similar joining of copper showcased a strength of 98 MPa. Additionally, the symmetric join in aluminum exhibited a strength of 93 MPa. The maximum tensile shear force is equal to 512 N at a maximum welding current of 14000 A. The pull-out failure mode occurs in the Cu-Al RSW joint. The maximum hardness was noted in the fusion zone (FZ). Relevant literature sources have supported and confirmed these outcomes.

11

Microstructure, Mechanical Properties, and Heat Distribution ANSYS model of CP Copper and 316 Stainless Steel Torch Brazing

Abtan Auday Awad, Mohammed Mohammed S., Alshalal Iqbal

Advances in Science and Technology. Research Journal

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2024

|

Vol. 18, no. 1

167--183

EN

Using torch brazing techniques, 316 stainless steel was brazed to CP copper using flux-coated low silver content filler with 20% Ag. The brazing torch utilized a fuel mixture of propane gas with oxygen to produce the required heating amount due to the possibility of economic interest in employing low-silver-content filler. The brazing filler's braze ability with SUS304 and copper was scrutinized and deeply analyzed. A ferrite barrier layer was made on the stainless-steel side, and an excellent brazed joint was produced. Metallurgical studies using an optical microscope and a scanning electron microscope (SEM) confirmed the production of a ferrite layer. This layer's advantages were carefully examined with metallurgical testing, electron diffraction scanning (EDS), EDS mapping, and EDS line analyses, including preventing copper intergranular penetration into the stainless-steel grain boundary. The mechanical properties of the brazed joint and its usability were assessed through Vickers microhardness and tensile tests on the brazing seam and both base metals. The results of the brazing process showed that using flux-coated low-silver brazing techniques produced strong joints with satisfactory mechanical properties. These techniques are a cost-effective alternative to high-priced brazing fillers with high silver content. Geometrical models simulated the heat distribution using ANSYS and SOLIDWORKS software to analyze penetration depth, joint quality, surface cracks, and the relation between molten filler density variation and the wetting process.

12

Damages of the Section Insulator Guide Caused by Electric Arc

Konieczny Jarosław, Labisz Krzysztof

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no. 2

214--225

EN

This article presents research on the influence of an electric arc on the properties and structure of a traction section guide made of ETP (Electrolytic Tough Pitch) copper in a segment insulator of a railway section. An electrical discharge occurring during use, which may accompany the passage of the pantograph current collector between adjacent guides, may cause many physical phenomena. In addition to existing guide wear mechanisms, such as friction, corrosion, and/or oxidation, the action of an electric arc also has a devastating effect on the guide in use, causing its complete destruction in extreme cases. The aim of the investigation was to determine what type of damage to the sectional guide in real operation conditions was caused by the impact of an electric arc that is induced when the pantograph passes from one guide to the adjacent one. The paper presents the results of tests on an operational guide made of hard electrolytic copper Cu-ETP, in particular the results of microscopic observations, the results of microscopic tests obtained using the ZEISS SUPRA 25 scanning electron microscope, as well as the analysis of the chemical composition in micro-areas (EDS - Energy-dispersive X- ray spectroscopy). On the basis of the tests carried out, it was found that the dominant destructive mechanism of the guide is the electric arc, the presence of elements from the external environment was also determined, and the degree of damage was analysed depending on the conditions and operating times.

13

Polskie górnictwo i hutnictwo miedzi w sztuce medalierskiej

Świsulski Dariusz

Wiadomości Elektrotechniczne

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2023

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R. 91, nr 9

82--96

PL

Polska jest jednym z największych producentów miedzi na świecie. W artykule przypomniano historię górnictwa miedzi od najdawniejszych lat przez odkrycie złóż miedzi przez Jana Wyżykowskiego do czasów współczesnych. Obecnie górnictwem i hutnictwem miedzi zajmuje się wiele przedsiębiorstw w ramach KGHM Polska Miedź. Ich opis zilustrowano zdjęciami: medali, plakiet i statuetek, które znajdują się w zbiorach autora.

EN

Poland is one of the largest copper producers in the world. The article presents the history of copper mining from the earliest years, the discovery of copper deposits by Jan Wyżykowski up to the present day. The mining and metallurgy of copper is currently carried out by companies in KGHM Polska Miedź. The descriptions are illustrated with photos of medals, plaques and statuettes, which are in the author's collection.

14

Biosorpcja jonów miedzi na granulkach alginianowych : skuteczność procesu w warunkach ustalonych

Trawczyńska Ilona, Kwiatkowska-Marks Sylwia

Przemysł Chemiczny

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2023

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T. 102, nr 12

1364--1366

PL

Przedstawiono symulację biosorpcji jonów miedzi na granulkach alginianowych dla ustalonych wartości temperatury procesu. Ze względu na koszty związane z etapem chłodzenia często wymagane jest prowadzenie procesów w temperaturze zbliżonej do temperatury otoczenia. Na podstawie zaproponowanego modelu matematycznego obliczono skuteczność procesu biosorpcji w wąskim zakresie temp. 20-25°C, często stosowanym w przemyśle. Uzyskane wyniki dowodzą dużej wrażliwości procesu biosorpcji na zmianę temperatury. Obliczone wartości efektywnego współczynnika dyfuzji Deᵀ mieszczą się w przedziale 0,55-0,67∙10⁻⁹ m²/s, a przedstawione wyniki potwierdzają możliwość łatwego prognozowania De za pomocą proponowanej metody.

EN

A math. model of the biosorption process of Cu ions by alginates was created. The biosorption efficiency was detd. using the values of the effective diffusion coeff. (De) depending on the temperature, pH of the Cu soln. (P) and alginate content in the granules (C). Formulas for calcg. P and C were developed for the biosorption process carried out at temp. in the range of 9.8-60.2°C. The results prove the sensitivity of the biosorption process to temp. changes. The calcns. enable easy prediction of the effective diffusion coeff. De of the biosorption process.

15

The effect of cooper, zinc and selenium on skin condition

Kulik Anna

Polish Hyperbaric Research

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2023

|

nr 2(83)

23--30

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.

PL

Pierwiastki śladowe są niezbędne dla zachowania homeostazy ustroju, warunkują prawidłowe funkcjonowanie organizmu człowieka. Mikroelementy wpływają na szereg procesów metabolicznych zachodzących w skórze właściwej i naskórku. Nadmiar lub niedobór pierwiastków śladowych może stanowić potencjalne zagrożenie dla zdrowia człowieka, a tym samym wpływać na kondycją skóry. W pracy dokonano przeglądu piśmiennictwa obejmującego zagadnienia wpływu miedzi, cynku i selenu na stan skóry.

16

The effect of water quality change on copper flotation

Acuña Claudio, Aedo Camila, Leiva Claudio, Flores Víctor

Physicochemical Problems of Mineral Processing

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2023

|

Vol. 59, iss. 5

art. no. 186190

EN

Given the significant consumption and future demand for water resources, this paper intends to find the conditions for using a flotation process with different water quality. One of the alternatives is using water under secondary treatment with industrial water mixtures to partly recycle domestic wastewater and maximize metallurgical benefits. Results show that using wastewater (only with secondary treatment) in flotation is detrimental to copper recovery. However, molybdenum recovery is significantly improved. For mixtures with 50 [%] wastewater, 50 [ppm] frother, 20 [ppm] collector, and pH 10, copper recovery decrease amounts to 0.4 [%], while molybdenum shows a 2.4 [%] recovery increase. In addition, copper concentrate grade decreases by 1.4 [%], while molybdenum grade remains. Therefore, using wastewater is viable, particularly in the case of molybdenum. So, this study proposes using of water mixtures in the copper depression stage to improve molybdenum recovery.

17

Recovery of base and precious metals from scrap TV boards using zig-zag air separator

Yazici Ersin Yener, Celep Oktay, Ibrahim Boulama Omar Yacine Lawan, Deveci Haci

Physicochemical Problems of Mineral Processing

|

2023

|

Vol. 59, iss. 5

art. no. 168255

EN

Waste of Electrical and Electronic Equipments (WEEE) is one of the fastest growing waste streams in the world. The treatment of WEEE with high content of precious metals (Au in particular) has received the most attention due to their high economic potential. The development of simple, environmentally friendly and cost-effective methods for the recovery of metals from “low-value” WEEE (e.g., <100 g/t Au) is important from the circular economy perspective. In this study, the separation of base (Cu) and precious (Ag) metals from scrap TV boards (STVBs) by using a zig-zag air separator was investigated. Size-reduced scrap STVBs (-1 mm) were subjected to separation tests after the removal of the fine fraction (-0.1 mm). The sized scrap material (-1 +0.1 mm) was determined to have a metal content of 15.4% Cu, 47 g/t Ag and 0.05% Fe, with no gold. In the air separation tests, the effect of air flow rate (4-16 m/s) on the recovery of metals was studied. Increasing the air flow rate resulted in low metal recoveries with concurrent high metal grades in the concentrate. Separation efficiency (%) calculations showed that the most efficient separation is obtained at the highest air flow rate of 16 m/s. At this flow rate, 15.4% of the material was recovered in the concentrate which contains 62.3% Cu and 198 g/t Ag with recoveries of 63.3% Cu and 73.9% Ag. The findings indicated that zig-zag air separators can be used to obtain a metal-rich fraction under suitable conditions of the flow regime.

18

Physicochemical properties and NH3-SCR catalytic performance of intercalated layered aluminosilicates

Szymaszek-Wawryca Agnieszka, Díaz Urbano, Samojeden Bogdan, Motak Monika

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 4

art. no. 171381

EN

The representative of natural layered clays, bentonite, was modified according to two routes and tested as a new catalyst for selective catalytic reduction of nitrogen oxides with ammonia (NH3-SCR). The natural acid-activated clay was ion-exchanged with Na+ or remained in H-form and pillared with metal oxides. In order to limit the number of synthesis steps, iron as an active phase was introduced simultaneously with Al2O3 during the intercalation procedure. Additionally, the samples were doped with 0.5 wt% of copper to promote low-temperature activity. It was found that the performed modifications resulted in disorganization of the ordered layered arrangement of bentonite. Nevertheless, acid activation and pillaring improved structural and textural parameters. The results of catalytic tests indicated that the samples containing Fe2O3 pillars promoted with Cu exhibited the highest NO conversion of 85% at 250°C (H-Bent-AlFe-Cu) and 75% at 300°C (Na-Bent-AlFe-Cu). What is important, activity of the protonated samples in the high-temperature region was noticeably affected by the side reaction of ammonia oxidation, correlated with the production of NO and resulting in N2O emission during the process comparing to Na-Bentonite catalysts.

19

Effects of lead nitrate and pre-aeration on the deportment of base/precious metals in cyanide leaching of a pyritic refractory gold concentrate

Deveci Hacı, Yazıcı Ersin Yener, Celep Oktay, Mercimek Murat, Demirel Cumhur, Çakmak Serkan, Cingöz Melih Baki, Kavlu Ömer Hami, Kömürcü Hüseyin

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 5

art. no. 166259

EN

This study was undertaken to improve gold and silver extraction from a pyritic gold flotation concentrate, which assayed 11 g/t Au, 42 g/t Ag, 0.21% Cu, 3.57% Zn, and 31% Fe. Direct cyanide leaching of the concentrate at 1.5 g/L NaCN yielded a low gold extraction (37%), confirming its refractory nature. Effects of lead nitrate (200-500 g/t Pb(NO3)2) and pre-aeration (24 h) before cyanide leaching at 1.5-3.5 g/L NaCN were investigated. Earlier studies have focused on the impact of these parameters on gold leaching. Besides gold, this study demonstrated the behaviour of silver and base metals (copper and zinc) from the pyritic gold concentrate. Adding lead nitrate had a negligible effect on gold extraction whilst improving silver extraction. Dissolution of copper was substantially suppressed by adding lead nitrate, i.e., from 23% (no Pb(NO3)2) to 4% (500 g/t Pb(NO3)2) over 24 h. Zinc dissolution was negligible (≤0.01%). Pre-aeration of the concentrate improved the gold and silver extractions by 4-14% and 23-44% at the subsequent cyanide leaching (1.5-3.5 g/L NaCN). However, it did not affect the leaching of copper. Only negligible leaching of zinc (≤0.6%) occurred during cyanide leaching. Pre-aeration also reduced cyanide consumption in subsequent cyanide leaching (1.5 g/L NaCN), i.e., from 2.83 kg/t to 2.03 kg/t NaCN per solids. These results suggested that lead nitrate can improve silver extraction while suppressing copper dissolution, which would be advantageous in the leaching-adsorption circuit (CIP), mitigating the dissolved copper-associated problems. Pre-aeration can also be suitable for improved gold/silver extractions and reduced reagent consumption.

20

Beneficiation of Artvin-Cerattepe copper-zinc ore by flotation

Seyrankaya Abdullah, Yontar Uğur, Canbazoğlu Mehmet, Özel Gizem, Kabaloğlu Sinan

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 5

art. no. 167499

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.