Efficient Separation and Recovery of Tellurium and Copper …
Sodium carbonate is a suitable tellurium trap that is commonly used to remove tellurium impurities from crude copper melt and recover tellurium from ... Fyzab C, Yjz A, Gmpb C (2017) Selection of reductants for extracting selenium and tellurium from degoldized solution of copper anode slimes. Trans Nonferrous Met Soc China …
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Efficient Separation and Purification Method for Recovering …
To minimize tellurium loss during reduction and facilitate tellurium–selenium separation, this study employed hydroxylamine hydrochloride for the selective reduction of tetravalent selenium. ... maintaining the pH below the threshold for tellurium hydrolysis throughout this process effectively minimizes tellurium impurities …
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Optimizing Thermoelectric Performance of Tellurium via …
Forming solid solutions is one of the most effective strategies to suppress the thermal conductivity of thermoelectric materials. However, the accompanying increase in impurity ion scattering usually results in an undesirable loss in hall mobility, negatively impacting the electrical transport properties. In this work, a tellurium–selenium (Te-Se) …
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Chemistry
Selenium (Se) was identified in 1818 by Berzelius as an elemental residue during the oxidation of sulfur dioxide from copper pyrites in the production of sulfuric acid. It is similar in properties to tellurium (discovered some 35 years earlier) and was named for the moon (selene in Greek) while tellurium had been named for the earth (tellus in Latin). Little …
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Preparation of Sulfur of High Purity
The nonvolatile impurities are removed on distilling the sulfur. The residual sulfuric acid is removed by a special extraction with distilled water. Methods are described for determining small amounts of the following impurities: Selenium, tellurium, arsenic, iron, carbon, sulfuric acid, and residue after ignition.
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Selective Separation and Recovery of Tellurium from …
method, concentration of impurities in the anodes, and the electrorening conditions. However, common components of the slimes are copper, silver, gold, selenium, tellurium, arsenic, bismuth, antimony, lead, barium, and platinum-group metals (PGMs) [5 –8]. Tellurium is a rare metalloid that is majorly produced from copper anode slime [8].
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Separation behavior of impurities and selenium reduction …
First, 4N grade tellurium was prepared as shown in Table 1.The major impurities in the tellurium (4N grade) were bismuth (Bi), antimony (Sb), tin (Sn), and selenium (Se) due to the characteristics of the source material, as we used thermoelectric devices recycled by pretreatment methods such as mechanical crushing, tumbling, and …
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Research and Industrial Application of Selenium and Tellurium …
Selenium and tellurium are typical trace elements, also called rare metals. They are necessarily associated with many sulfide ores or heavy non-ferrous metals. ... TeO 2 is purified by repeated dissolution and reprecipitation of the TeO 2, which eliminates the majority of heavy metal impurities. The final TeO 2 precipitate, contaminated ...
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Theoretical Study on the Separation of Impurity …
Abstract. Theoretical research on the separation of tellurium by vacuum distillation from crude selenium could provide further key data support for industrial …
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Theoretical study of selenium and tellurium …
The presence of impurities, in particular selenium and tellurium, in ZnO-based clusters can affect their structural and spectroscopic properties. Some of these doped …
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Removal of impurity Pb during crude selenium purification …
In this work, based on the Eh-pH diagrams of the Pb–Se–H 2 O and Pb–Te–H 2 O system, an efficient process of controlling potential oxidation and vacuum distillation for removing impurity Pb from crude selenium was proposed. The occurrence state and the removal behavior of impurity Pb in crude selenium were deeply investigated and ...
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Efficient Separation and Purification Method for …
In this study, we developed a concise and efficient chemical method that does not require expensive reagents or equipment, enabling the separation and …
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Research and Industrial Application of Selenium …
Introduction. Selenium (Se, atomic number 34, atomic weight 78.96) lies between arsenic and bromine and between sulfur and tellurium (Te, atomic number 52, atomic weight …
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Behavior of Impurity Inclusions during Vacuum Distillation of Tellurium …
Non-volatile impurities in molten tellurium, particularly carbon, that may have a concentration as high as 5 × 10 14 molecules/m 3, have the chance to occupy a certain number of positions at the ...
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Optimizing Thermoelectric Performance of Tellurium via …
However, the accompanying increase in impurity ion scattering usually results in an undesirable loss in hall mobility, negatively impacting the electrical transport properties. In this work, a tellurium-selenium (Te-Se) solid solution with trace antimony (Sb) doping was synthesized via the high pressure and high temperature method.
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Modeling of selenium and tellurium removal from copper …
Since then, Vale has used cuprous sulfate to remove selenium and tellurium impurities from copper sulfate-sulfuric acid electrolyte prior to electrowinning (Stewart et al., 1985). In this plant, selenium and tellurium are dissolved during high pressure oxidative leaching of a copper sulfide residue to give Se IV/VI and Te IV/VI species into …
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Tellurium, from Copper Anode Slime to High Purity …
Tellurium and selenium belong to the chalcogen group (Group VI of the periodic table). All the chalcogens have six valence electrons, and their most common oxidation states are 2, + 2, + 4, and + 6. There is a substantial similarity between the properties of Te, Se, and S. Because of the close chemical similarities, tellurium, and selenium ...
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REMOVAL OF THE IMPURITIES (selenium, tellurium, etc) …
Research has been undertaken to establish the flowsheet of a selective leaching process for the elimination of the main impurities contained in the anodic slimes of copper refining in order to obtain a precious metals concentrate free of arsenic, antimony, selenium and tellurium, which may then be treated as common precious metals raw …
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Minerals | Free Full-Text | Tellurium and Selenium …
In the Ozernoe uranium occurrence, the main mineral-concentrator of selenium is molybdenite, which contains up to 16 wt.% of Se in the marginal parts of the grains. The molybdenite is rich in Re (up to 1.2 wt.%), and the impurity of Re is irregularly distributed in molybdenite flakes and spherulites.
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Evaporation Regularities of Elemental Selenium in the …
where (omega ) is the evaporation rate in g·cm −2 ·s, which represents the mass change ((Delta m), g) of selenium at a certain time ((Delta t), s) and evaporation area (A, cm 2) during the distillation process.. Therefore, the evaporation rate of elemental selenium can be obtained only by experimentally measuring mass changes during the …
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An investigation of copper and selenium recovery from …
Impurities in anode slimes can be classified into the groups based on their electrochemical potentials and chemical behaviors (Table 1). ... Selenium and tellurium from copper refinery slimes and their changing applications. Proc. Eur. Metall. Congr., 2 (2007), pp. 571-585.
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Experimental Analysis of High Purity Tellurium Prepared by …
Most of the impurities in metallic tellurium can be removed relatively well by zone refining method. The impurity selenium in tellurium is an exception, the impurity Se has similar properties to tellurium and its equilibrium partition coefficient k 0 (0.44) is close to 1.0, so the conventional zone refining method is less effective in removing the …
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Research and Industrial Application of Selenium and …
Selenium (Se, atomic number 34, atomic weight 78.96) lies between arsenic and bromine and between sulfur and tellurium (Te, atomic number 52, atomic weight 127.61) in Group 6A (chalcogens) in the periodic table. It was discovered in 1817 by a Swedish chemist as a contaminant in sulfuric acid. Its name was derived from the Greek selene, meaning ...
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Optical Properties of Tellurium and Selenium
The optical properties of tellurium and of trigonal and amorphous selenium have been investigated at wavelengths extending from the intrinsic absorption edge to about …
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Physico-chemical properties of selenium–tellurium …
Abstract. Selenium and tellurium are both energy critical elements as defined by the American Physical Society and the Materials Research Society. When mixed together, both elements form an alloy.
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Name the common elements present in the anode mud in
In the electrolytic refining of copper, the anode mud contains antimony, selenium, tellurium, silver gold and platinum. These are impurities in blister copper. They are less reactive and unaffected by C u S O 4 − H 2 S O 4 solution and hence, settle down under anode as anode mud.
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Tellurium, from Copper Anode Slime to High Purity …
Tellurium is recognized as one of the critical elements[9,10,11,12] with an approximate production rate of 480 tons per year (2019), and about 90 pct of it comes from copper anode slime.[2,7] Major components of copper anode slime are copper, sulfur, silver, selenium, arsenic, lead, gold, nickel, antimony, and tellurium.Apart from copper anode …
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The Behaviour of Selenium Impurities During the Addition …
The Behaviour of Selenium Impurities During the Addition of Se-Containing Manganese to Steel Melt. M. Reza Aboutalebi, ... Given that selenium and its compounds are potentially toxic and damaging to the work place and environment, effluents have to be treated in a controlled manner. In order to determine how selenium typically distributes ...
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Chapter 2 Preparation of High-Purity Cadmium, Mercury, and Tellurium
It has been reported that the impurities like Se, As, Na, K, Mg and S are more difficult to remove using vacuum distillation [7]. Out of the various purification techniques for tellurium, multi-pass zone refining is the ultimate purification process [7,8] as majority of impurities in tellurium matrix have segregation coefficient far from unity.
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Selenium, Tellurium and Polonium
Selenium is also recovered from the sludge accumulating in sulfuric acid plants and from electrostatic precipitator dust collected during the processing of copper and lead. Detailed procedures for isolation and purification depend on the relative concentrations of selenium, tellurium, and other impurities, but a typical sequence involves ...
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