scholarly journals Copper Cathode Contamination by Nickel in Copper Electrorefining

Metals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1758
Author(s):  
Mika Sahlman ◽  
Jari Aromaa ◽  
Mari Lundström

Nickel behavior has a significant role in the electrorefining of copper, and although it has been extensively studied from the anode and electrolyte point of view over the past decades, studies on nickel contamination at the cathode are limited. In the current paper, three possible contamination mechanisms—particle entrapment, electrolyte inclusions and co-electrodeposition—were investigated. Copper electrorefining (Cu-ER) was conducted at the laboratory scale, and the cathodes were analyzed by scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS) and flame atomic absorption spectroscopy (AAS). Particle entrapment was studied by adding NiO and Fe2O3 to the system to simulate nickel anode slime, and the experiments were replicated with industrial anode slime material. The possibility of electrolyte entrapment due to nodulation was explored through the addition of graphite to produce nodules on the cathode. Co-electrodeposition was analyzed by experiments that utilized a Hull cell. The results indicate that particle entrapment can occur at the cathode and is a major source of the nickel contamination in Cu-ER, whereas nickel compounds were not shown to promote nodulation. Inclusions of bulk electrolytes within the surface matrix were observed, proving that electrolyte entrapment is possible. As co-electrodeposition of Ni in Cu-ER is thermodynamically unlikely, these experimental results also verify that it does not occur to any significant extent.

1981 ◽  
Vol 35 (5) ◽  
pp. 502-505 ◽  
Author(s):  
J. J. Labrecque ◽  
D. Adames ◽  
W. C. Parker

A rapid method is presented for the simultaneous determinations of thorium, niobium, lead, and zinc in lateritic material from Cerro Impacto, Estado Bolívar, Venezuela. This technique uses a PDP—11/05 processor—based photon induced x-ray fluorescence system. The total variations of approximately 5% for concentrations of approximately 1 and 10% for concentrations of approximately 0.1% were obtained with only 500 s of fluorescent time. The values obtained by this method were in agreement with values measured by conventional flame atomic absorption spectroscopy for lead and zinc. The values for thorium measured were in agreement with the reported values for the reference materials supplied by NBL.


2014 ◽  
Vol 878 ◽  
pp. 163-170 ◽  
Author(s):  
Liang Qu Huang ◽  
Ya Fan Bi ◽  
Lin Lin Mu ◽  
Hong Bo Zhang

Production of electrolytic manganese metal inevitably produces a certain amount of solid wasteelectrolytic manganese anode slime, with a high manganese content, but its difficult to recycle due to the presence of other impurities. Firstly, the washing method was used to remove the anode slime soluble salts, then its chemical composition and phase were analyzed. The flame atomic absorption spectrometer and X-ray fluorescence (XRF) analysis showed the anode slime mainly contained Mn, Pb, Ca, Fe, Cr, K, Se and other metal elements, with the average manganese content 45% and the lead 3.5%;X-ray diffraction (XRD) preliminary analysis showed that the anode slime was a colloidal system mainly containing the spinel structure of MnO2 and complex salts PbMn8O16xH2O phase, by high temperature roasting, the anode slime transformed from hexagonal system to cubic system , and the basic structure unit from edges connection to surfaces connection,the change of length,angle and fracture of manganese-oxygen bond provided the channel for the lead leaching;TG-DTA analysis showed that anode slime was dominated by water loss below 400°C,and started to lose oxygen beyond 425°C, and clear endothermic peak was observed at 500°C and 700°C, which showed the anode slime crystal structure changed at 500°C, anode slime weight loss tending to be gentle with some Mn2O3 generation at 700°C, and roasted crystal stabilizing to Mn2O3. Preliminary roasting and leaching purification technology route was proposed according to the above analysis results, and analysis of the purification process related factors was made. Under the condition of natural ventilation, anode slime was roasted at 700°C, and fully leached in 2mol/L HAc , with liquid-solid ratio 10:1, then leached anode slime was characterized by XRD and flame atomic absorption test, the results showed that anode slime manganese content increased from 45% to 67.5%, the lead content decreased from 3.5% to 0.1%, XRD indicated that the anode slime existing phase was Mn2O3. Anode slime after purification treatment can be further used for battery manganese source material, which provides an effective approach for the recovery of manganese anode slime utilization.


2016 ◽  
Vol 20 (06) ◽  
pp. 677-688 ◽  
Author(s):  
Ahmad Shaabani ◽  
Zeinab Hezarkhani

Functionalized wool with cobalt(II), copper(II), and iron(II) tetrasulfophthalocyanine (CoTSPc@wool, CuTSPc@wool, and FeTSPc@wool) have been synthesized and their structures characterized by flame atomic absorption spectroscopy (FAAS), FT-IR, UV-vis, X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and the energy dispersive spectroscopy (EDS) analysis. The catalytic activity of the synthesized catalysts was investigated for the aerobic oxidation of alkyl arenes and alcohols to their corresponding carbonyl compounds in the absence of any co-promoter and additional oxidizing reagent. We found the best catalyst for the mentioned reactions is the CoTSPc@wool from the solvent, conversion, temperature, and reaction time point of views. The synthesized catalysts can be readily recycled and reused for several runs without significant loss of efficiency.


2021 ◽  
Author(s):  
Wanderson S. Silva ◽  
Patrícia F. Santos ◽  
Jair C. C. Freitas ◽  
Miguel A. Schettino ◽  
Edson C. Passamani ◽  
...  

Abstract Ni metal particles, with sizes ranging from 70 to 110 nm, dispersed in activated carbon produced from the babassu coconut endocarp (BAC) were successfully synthesized and evaluated by scanning electron microscopy, dispersive energy X-ray spectroscopy, flame atomic absorption spectroscopy and powder X-ray diffraction. These hybrid BACNi-X materials (where X is the Ni / BAC ratio, equal to 10, 20 or 30) exhibit crystalline Ni particles with suitable magnetic properties, shown by increased saturation magnetization and a gradual reduction in coercive fields (varying 80 to 150 Oe) as the Ni content increases. Relatively large values ​​of pore volume (in the range of 0.28-0.37 cm3/g), specific surface area (560-740 m2/g) are achieved, favoring their applications for magnetic remediation of mimetic contaminated effluents. All hybrid samples were tested positively for the adsorption of methylene blue in contaminated synthetic effluents and the greatest removal was achieved by the hybrid sample BACNi-10, which has the largest specific area and reasonable magnetic properties that allowed the manipulation of the sample by an external field.


2020 ◽  
Vol 12 (19) ◽  
pp. 7931
Author(s):  
Sanmei Li ◽  
Mingda Wu ◽  
Linghong Lu ◽  
Jiabao Zhu

Humin is the waste residue from the process of preparing humic acid, which accounts for a large proportion of the raw material (weathered coal humic acid). Its Cd(II) adsorption performance is far inferior to that of humic acid. How to regenerate humin is of great significance to the low-cost treatment of Cd(II) pollution in wastewater. In this study, humin was modified by hyperbranched polyethyleneimine to enhance the adsorption capacity for Cd(II). Fourier transform infrared spectroscopy and the X-ray photoelectron spectrometer showed that hyperbranched polyethyleneimine was grafted to the surface of humin. Flame atomic absorption spectroscopy showed that the saturated Cd(II) adsorption capacity of the modified humin was increased to 11.975 mg/g, which is about 5 times than that of humin and is also higher than that of humic acid. The adsorption kinetics, adsorption isotherm, and thermodynamic properties of humic acid, humin, and modified humin were also studied. This study may provide a foundation for research utilizing natural resources to reduce heavy metal pollution in the environment.


2022 ◽  
Author(s):  
Aleksey V. Smirnov ◽  
Dmitriy S. Semenov ◽  
Ekaterina S. Ahkmad ◽  
Anna N. Khoruzhaya ◽  
Sergey Aleksandrovich Kruchinin

Diagnostic studies carried out using any medical equipment require comprehensive control, which is provided by a number of regulatory documents. Particular attention is paid to X-ray imaging methods, but in the field of magnetic resonance imaging (MRI), one can notice both the lack of this attention and the multidirectional efforts to normalize. This is understandable - this diagnostic method is not based on the use of ionizing radiation, and although magnetic fields have some effect on human health, especially on personnel who work in MRI rooms all the time, they are safe for patients who come to the diagnostic procedure from time to time. time and do not have in their body foreign metal (steel implants) or electronic (pacemakers, neurostimulators) objects. However, ignorance and non-compliance with both advisory and mandatory requirements can significantly increase the risk of harm to patients or staff, as well as lead to a decrease in the quality of imaging and diagnostics. A separate feature of the field of MRI regulation is that over the past decades, more than a dozen different standards, sanitary norms, rules, letters and recommendations have been published or revised, a significant part of which complement or duplicate each other, or completely contradict each other. As a result, the need to ensure compliance of the MRI room / department with the requirements of regulatory documents is greatly complicated. This paper provides an overview of the regulatory documentation in force in Russia related to the organization and functioning of an MRI room / department, highlights the aspects that are most important from the point of view of safe and high-quality operation, and formulates the steps necessary to modernize the system, both from the point of view of the quality of diagnostics. and the safety of MRI studies.


Author(s):  
R. E. Herfert

Studies of the nature of a surface, either metallic or nonmetallic, in the past, have been limited to the instrumentation available for these measurements. In the past, optical microscopy, replica transmission electron microscopy, electron or X-ray diffraction and optical or X-ray spectroscopy have provided the means of surface characterization. Actually, some of these techniques are not purely surface; the depth of penetration may be a few thousands of an inch. Within the last five years, instrumentation has been made available which now makes it practical for use to study the outer few 100A of layers and characterize it completely from a chemical, physical, and crystallographic standpoint. The scanning electron microscope (SEM) provides a means of viewing the surface of a material in situ to magnifications as high as 250,000X.


Author(s):  
E. Loren Buhle ◽  
Pamela Rew ◽  
Ueli Aebi

While DNA-dependent RNA polymerase represents one of the key enzymes involved in transcription and ultimately in gene expression in procaryotic and eucaryotic cells, little progress has been made towards elucidation of its 3-D structure at the molecular level over the past few years. This is mainly because to date no 3-D crystals suitable for X-ray diffraction analysis have been obtained with this rather large (MW ~500 kd) multi-subunit (α2ββ'ζ). As an alternative, we have been trying to form ordered arrays of RNA polymerase from E. coli suitable for structural analysis in the electron microscope combined with image processing. Here we report about helical polymers induced from holoenzyme (α2ββ'ζ) at low ionic strength with 5-7 mM MnCl2 (see Fig. 1a). The presence of the ζ-subunit (MW 86 kd) is required to form these polymers, since the core enzyme (α2ββ') does fail to assemble into such structures under these conditions.


Author(s):  
J.D. Shelburne ◽  
G.M. Roomans

Proper preparative procedures are a prerequisite for the validity of the results of x-ray microanalysis of biological tissue. Clinical applications of x-ray microanalysis are often concerned with diagnostic problems and the results may have profound practical significance for the patient. From this point of view it is especially important that specimen preparation for clinical applications is carried out correctly.Some clinical problems require very little tissue preparation. Hair, nails, and kidney and gallbladder stones may be examined and analyzed after carbon coating. High levels of zinc or copper in hair may be indicative of dermatological or systemic diseases. Nail clippings may be analyzed (as an alternative to the more conventional sweat test) to confirm a diagnosis of cystic fibrosis. X-ray microanalysis in combination with scanning electron microscopy has been shown to be the most reliable method for the identification of the components of kidney or gallbladder stones.A quantitatively very important clinical application of x-ray microanalysis is the identification and quantification of asbestos and other exogenous particles in lung.


Chelovek RU ◽  
2020 ◽  
pp. 18-53
Author(s):  
Sergei Avanesov ◽  

Abstract. The article analyzes the autobiography of the famous Russian philosopher, theologian and scientist Pavel Florensky, as well as those of his texts that retain traces of memories. According to Florensky, the personal biography is based on family history and continues in children. He addresses his own biography to his children. Memories based on diary entries are designed as a memory diary, that is, as material for future memories. The past becomes actual in autobiography, turns into a kind of present. The past, from the point of view of its realization in the present, gains meaning and significance. The au-thor is active in relation to his own past, transforming it from a collection of disparate facts into a se-quence of events. A person can only see the true meaning of such events from a great distance. Therefore, the philosopher remembers not so much the circumstances of his life as the inner impressions of the en-counter with reality. The most powerful personality-forming experiences are associated with childhood. Even the moment of birth can decisively affect the character of a person and the range of his interests. The foundations of a person's worldview are laid precisely in childhood. Florensky not only writes mem-oirs about himself, but also tries to analyze the problems of time and memory. A person is immersed in time, but he is able to move into the past through memory and into the future through faith. An autobi-ography can never be written to the end because its author lives on. However, reaching the depths of life, he is able to build his path in such a way that at the end of this path he will unite with the fullness of time, with eternity.


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