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1

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.

2

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.

3

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.

4

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

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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.

5

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.

6

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.

7

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.

8

The effect of cooper, zinc and selenium on skin condition

Kulik Anna

Polish Hyperbaric Research

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2023

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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.

9

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

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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.

10

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

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2023

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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.

11

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.

12

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.

13

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.

14

Manufacturing Cu-Pb alloys and studying efficiency in resisting oxidation

Sufian Amina, Hamood Mahmood Ahmad Al- Jiboori

Ochrona przed Korozją

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2023

|

nr 12

388--392

EN

Binary alloys of copper and lead were produced by casting these elements in specially designed moulds with dimensions appropriate to the tests to be carried out on them. The effectiveness of these alloys in resisting oxidation was then studied in an atmosphere of a mixture of sodium chloride vapour and sodium sulphate at specific concentrations and heating the mixture to 180°C. Recently, corrosion has become a major problem in the overall performance of many engineering devices due to automotive exhaust gases produced by the internal combustion engine, which leads to corrosion of materials that make up some components of engineering industries. Copper also has good corrosion performance due to the formation of a copper oxide layer, which has made it the most important material in industrial applications. Through this research, we have achieved the desired goal as the alloys produced have shown their efficiency in resisting saline and acidic conditions and at high levels. The best sample is Cu95Pb5 and Cu90Pb10 with little difference between them in terms of efficiency. The aim of this work is to produce alloys and study their efficiency in resisting oxidation at high temperatures.

PL

Binarne stopy miedzi i ołowiu zostały wytworzone metodą odlewania w specjalnie zaprojektowanych formach o wymiarach dostosowanych do badań. Odporność stopów na utlenianie została zbadana w atmosferze mieszaniny oparów chlorku sodu i siarczanu sodu w określonych stężeniach i po podgrzaniu mieszaniny do 180°C. Korozja jest poważnym problemem, zaburza funkcjonowanie wielu urządzeń inżynieryjnych. Jej źródłem są m.in. spaliny wytwarzane przez silniki spalinowe. Miedź ma dobre właściwości antykorozyjne ze względu na warstwę tlenku miedzi, tworzącą się na jej powierzchni w wyniku utleniania. Z tego względu jest głównym materiałem stosowanym w przemyśle. Badane stopy miedzi i ołowiu wykazały wysoką odporność na działanie soli i kwasów w dużych stężeniach. Najlepsze wyniki uzyskano dla stopów Cu95Pb5 i Cu90Pb10 (różnica między nimi była niewielka). Celem pracy było zbadanie odporności wytworzonych stopów na utlenianie w wysokich temperaturach.

15

The Influence of the Gray Forest Soil Moisture Level on the Accumulation of Pb, Cd, Zn, Cu in Spring Barley Grain

Razanov Serhii, Husak Oksana, Hnativ Petro, Dydiv Andrii, Bakhmat Oleh, Stepanchenko Vitalii, Pryshchepa Alla, Shcherbachuk Victor, Mazurak Oksana

Journal of Ecological Engineering

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2023

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Vol. 24, nr 7

285--292

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.

16

The use of algae to remove copper and lead from industrial wastewater

Cygnarowska Katarzyna

Geology, Geophysics and Environment

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2023

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Vol. 49, no. 1

85--93

EN

The aim of the research was to evaluate the effectiveness of the removal of Cu and Pb ions by algae. The experiments were carried out in the presence of two algal populations: a pure culture of Raphidocelis subcapitata, and a mixed chlorophyta population. The research involved a model study, experiments in the presence of wastewater from the manufacture of batteries, and the study of process kinetics. The wastewater pH was 4.0, and the initial concentrations of metal ions in the wastewater were 95.4 mg/L for Pb and 48.3 mg/L for Cu, respectively. The maximum sorption capacity of the pure Raphidocelis subcapitata culture was 14.8 mg/g d.m. for Pb, corresponding to the removal of 72% of lead, and 6.1 mg/g d.m. for Cu, corresponding to the removal of 43% of copper from the wastewater. The best ion sorption efficiency in the case of the mixed chlorophyta population was 7.0 mg/g d.m. for Pb, i.e., 61% removal of lead, and 12.8 mg/g d.m. for Cu, i.e., 69% removal of copper ions from the wastewater. The optimum duration of the process was found to be 1 hour, since the majority of biomass samples reached the maximum saturation after that time. On the basis of the obtained results (Lagergren models), it was found that the dominant mechanism of the process was chemisorption.

17

Economic assessment of the Northern Copper Belt deposits : a future resource base of copper and silver ores in SW Poland

Bieńko Tomasz, Wierchowiec Jan, Speczik Stanisław

Geological Quarterly

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2023

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Vol. 67, No. 3

67--28

EN

Seven undeveloped sediment-hosted stratiform Cu-Ag deposits constitute a future resource base of copper and silver ores in the Fore-Sudetic Monocline in SW Poland. Among these, four have only recently been discovered and documented: Nowa Sól, Sulmierzyce North, Mozów (forming a part of the Northern Copper Belt) and Żary. The three remaining deposits – Bytom Odrzański, Głogów and Retków – surround the currently mined New Copper District to the north-west, north and north-east. Polish Cu-Ag deposits are polymetallic: copper, silver, lead, nickel as well as subordinate rhenium and gold are currently extracted. However, they show high reporting of other by-product metals, such as cobalt, molybdenum, vanadium, zinc and rare earth elements.Unit ore values expressed in US dollars per metric ton of ore have been calculated for deposits in the Northern Copper Belt to compare them with other undeveloped and mined Polish sediment-hosted stratiform Cu-Ag deposits. The calculated unit ore values for the deposits studied are primarily influenced by copper, with a significant contribution (up to 29%) from silver. In terms of base metals other than copper, their contribution to the unit ore values is here relatively low, accounting for only 1–11% of the total value. The proportions of silver and lead in the unit ore value show a trend: they tend to be lower in the vicinity of oxidized fields and gradually increase with distance from these oxidized areas. The share of nickel in the unit ore value, on the other hand, is not influenced by distance from the oxidized fields. Instead, it is dependent on factors such as the thickness and organic content of the shale ore, which affect the accumulation of non-ferrous, redox-sensitive by-product metals, including nickel. Furthermore, we provide a comparative analysis of the total unit ore value among Polish sediment-hosted stratiform Cu-Ag deposits. Particular emphasis is placed on the deposits that constitute the future resource base of copper and silver ores in southwest Poland. A market perspective is drawn to highlight the influence of metal price fluctuations on the unit ore values of the various deposits. By examining the dynamic nature of metal prices, the study offers insights into how changes in market conditions can impact the economic viability of deposits located in different parts of the Fore-Sudetic Monocline. The deposits that constitute the future resource base of copper and silver in Poland show remarkably high copper and silver grades, resulting in significantly higher unit ore values compared to other world-class deposits of different types such as porphyry, epithermal, and IOCG (iron oxide copper gold) deposits.

18

Effects of HE and ECAP processes on changes in microstructure and mechanical properties in copper, iron and zinc

Kulczyk Mariusz, Skorupska Monika, Skiba Jacek, Przybysz Sylwia, Smalc-Koziorowska Julita

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2023

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Vol. 71, nr 3

art. no. e145563

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.

19

Investigation of Multi-Cold Rolling Passes on Mechanical Characteristics and Surface Quality of AlCuV Alloy

Shaban Nabeel Abu, Al-Qawabah Safwan, Alkhaldi Hashem S.

Advances in Science and Technology. Research Journal

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2023

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Vol. 17, no 5

68--76

EN

In this study, the effect of rolling angle orientation namely; 0, 45, and 90 degrees, and three rolling passes on the mechanical behavior of Al-Cu after vanadium addition were investigated. Al-4%Cu and Al-4%Cu-0.1%V sheets were produced and rolled from 4 mm to 3 mm followed by 3 to 2 mm, and finally from 2 mm to 1.3 mm. After each pass, the tensile test was performed in three directions from which the maximum tensile force, deformation energy, microhardness, and average surface roughness (Ra) were determined. A pronounce finding is that the addition of both additions of 0.1% vanadium to Al-4%Cu alloy and multi-rolling passes resulted in reducing the deformation energy by 85.4, and the maximum tensile forces reduced by 56.6%, this resulted in reduction of production cost of AlCuV alloys, furthermore, it resulted in reducing the anisotropy of AlCuV alloy. Additionally, the average microhardness was enhanced for Al-Cu and AlCuV alloy, whereas the Ra was in maximum enhanced for AlCuV alloy of about 64.9%.

20

Corrosion tests of metal pipes in drinking water systems using electrochemical methods

Adetunji Olayide R., Oyelowo Mojisola A., Adekunle Nurudeen O., Adeogun Abideen I., Okediran Iliyas.K

Ochrona przed Korozją

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2022

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nr 2

43--49

EN

Metals constitute some of the major materials for making water delivery pipelines. However, the service life of metallic pipelines is affected by corrosion. Mild Steel (MS), Galvanized Steel (GS) and Copper were selected based on their strength and corrosion resistance. They were subjected to Potentiodynamic Polarization (PP) and Electrochemical Impedance Spectroscopy (EIS) investigations using water as the electrolyte from selected sampling points (A, B, C, D and E) on the University of Lagos, Akoka water distribution network. Corrosion current density (Icorr) and Impedance (Z) were measured in A/mm2 and ohms respectively. The morphology of the corroded samples was examined using Scanning Electron Microscope (SEM). The result obtained from PP investigation showed Icorr in the low range for the three metals considered. Similarly, for EIS, Z values measured were high for MS, GS and Cu. Both methods indicated that Cu was the most corrosion resistant material, closely followed by GS and lastly MS. The SEM images clearly showed that among the three specimens, the morphology of Cu remained unaffected by the environment. On the other hand, MS and GS showed evidences of corrosion with pits. The large amounts of iron established in the studied water distribution system, confirmed corrosion of water pipes.

PL

Metale są jednym z głównych materiałów konstrukcyjnych wodociągów. Jednak trwałość metalowych rurociągów jest ograniczona ze względu na korozję. Ze względu na wytrzymałość i odporność na korozję do budowy rurociągów stosuje się stal miękką (MS), stal ocynkowaną (GS) i miedź. Próbki pobrane w wybranych miejscach (A, B, C, D i E) sieci wodociągowej Akoka poddano na Uniwersytecie w Lagos badaniom metodą polaryzacji potencjodynamicznej (PP) i elektrochemicznej spektroskopii impedancyjnej (EIS) z zastosowaniem wody jako elektrolitu. Gęstość prądu korozyjnego (Icorr) i impedancję (Z) zmierzono odpowiednio w A/mm2 i omach. Morfologię skorodowanych próbek zbadano za pomocą skaningowego mikroskopu elektronowego (SEM). Wynik otrzymany w badaniach PP wykazał Icorr w niskim zakresie dla trzech rozważanych metali. Podobnie w przypadku EIS zmierzone wartości Z były wysokie dla MS, GS i Cu. Obie metody wskazywały, że miedź jest najbardziej odpornym na korozję materiałem, a następnie ocynkowana stal o podobnych właściwościach i na końcu stal miękka. Na mikrofotografiach SEM wyraźnie widać, że spośród trzech próbek metali środowisko nie miało wpływu na morfologię Cu. MS i GS wykazały ślady korozji z wżerami. Duże ilości żelaza stwierdzone w badanym systemie wodociągowym potwierdziły korozję rur.