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].
Theoretical study of selenium and tellurium impurities in …
The investigated structures have been produced through the doping of (ZnO) 6 clusters by replacing an oxygen atom with a selenium or a tellurium atom at each time. The ground state geometric parameters of (ZnO) 6 structures, containing selenium or tellurium atoms as substitutional impurities, were calculated using density functional theory (DFT ...
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 …
Selective Separation of Tellurium and Copper from Crude Selenium …
The microscopic impurity elemental distribution was analyzed using an electron probe microanalyzer (EPMA), and it shows that the impurities were relatively concentrated and gathered in crude selenium.
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.
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) …
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 …
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.
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 …
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 ...
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.
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 …
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 …
Experimental Analysis of High Purity Tellurium …
Zone refining is commonly used as a reliable final purification step to achieve higher purity levels of tellurium. However, the removal of Selenium (Se)—the most …
A clean and efficient method for purifying crude selenium …
Deep oxidation of selenium was carried out to remove the impurity tellurium. Finally, high purity selenium with a purity of more than 6N was prepared by vacuum distillation. Dutton et al [ 26 ] purified selenium by multiple oxidation method, studied the process of selenium vapor oxidation to SeO 2, and carried out complete or …
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 ...
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 ...
Purification of crude selenium by vacuum distillation and analysis
The purity of the initial crude selenium is 99.4%, and S, As, Bi, Fe, and Si account for >84.95% of the total impurities. Most impurities were removed effectively by TCVD, and the total content of impurities decreased from 2997.38 ppmw to <79.08 ppmw; in other words, MG-Se (99.4%) was purified to >99.992%.
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 …
Innovative green approach for the selective extraction of …
First, the states of impurities in selenium sludge were characterized in detail. Second, hydrogen peroxide (H 2 O 2) was employed for converting the impurity phases in the selenium sludge slurry, thereby decreasing the volatilization of impurities in the later distillation process. Third, a vacuum distillation process was carried out to ...
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 …
Experimental investigation and calculation for Te-X (X=Cu, …
During the experiment, tellurium's higher saturation vapor pressure than copper and lead [16] can evaporate tellurium from the alloy system during vacuum distillation, leaving impurity elements in the liquid phase. Therefore, high-purity Te can be obtained by condensing vapor phase substances.
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 ...
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.
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 …
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 ...
Extraction of tellurium from lead and copper bearing feed …
The main sources of tellurium in the lead smelting process are copper dross (mass of solid impurities floating on a molten metal), alkaline skimming and rich sliver dross intermediate products ... where slimes were roasted at 530–650 °C to convert all of the tellurium and selenium to hexavalent state without volatilization (Fig. 5). The ...
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 ...
Activation analysis for selenium and tellurium trace impurities …
Destructive and non-destructive activation analysis for selenium and tellurium has been studied. In destructive analysis the selenium and tellurium activities are co-extracted from the irradiated and dissolved matrix elements with dithizone/CCl 4, reagent in a hot-chamber by remote manipulation, then separated from each other by diethylammonium-N,N …
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 …
