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Tytuł:
Effect of Magnet Scrap Size on the Extraction Behavior of Heavy Rare Earth Elements by Liquid Metal Extraction
Autorzy:
Nam, Sun-Woo
Rasheed, Mohammad Zarar
Park, Sang-Min
Lee, Sang-Hoon
Kim, Do-Hyang
Kim, Taek-Soo
Powiązania:
https://bibliotekanauki.pl/articles/355705.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
liquid metal extraction
rare earth elements
recycling
oxidation
magnet scrap
Opis:
Liquid metal extraction (LME) process results in 100% neodymium (Nd) extraction but the highest extraction efficiency reportedfor Dysprosium (Dy) so far is 74%. Oxidation of Dy is the major limiting factor for incomplete Dy extraction. In order to enhance the extraction efficiency and to further investigate the limiting factors for incomplete extraction, experiments were carried out on six different particle sizes of under 200 μm, 200-300 μm, 300-700 μm, 700-1000 μm, 1000-2000 μm and over 2000 μm at 900°C with magnesium-to-magnet scrap ratio of 15:1 for 6, 24 and 48 hours, respectively. This research identified Dy2 Fe17 in addition toDy2 O3 phase to be responsible for incomplete extraction. The relationship between Dy2 Fe17 and Dy2O3 phase was investigated, and the overall extraction efficiency of Dy was enhanced to 97%.
Źródło:
Archives of Metallurgy and Materials; 2020, 65, 4; 1273-1276
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Bismuth and Rare Earth Elements on Graphite Structure in Different Section Thicknesses of Spheroidal Graphite Cast Iron Castings
Autorzy:
Glavas, Z.
Strkalj, A.
Maldini, K.
Kozina, F.
Powiązania:
https://bibliotekanauki.pl/articles/353810.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
spheroidal graphite cast iron casting
graphite structure
bismuth
rare earth elements
microstructure
Opis:
Effects of additions of 0.00064, 0.001 and 0.0042 wt.% Bi on the graphite structure in the section thicknesses of 3, 12, 25, 38, 50, 75 and 100 mm of spheroidal graphite cast iron castings containing 2.11 wt.% Si and rare earth (RE) elements (Ce + La + Nd + Pr + Sm + Gd) in the range from 0.00297 to 0.00337 wt.% were analyzed in this paper. Addition of Bi was not necessary for obtaining high nodule count and nodularity higher than 80% in section thicknesses of 3, 12 and 25 mm. RE elements showed a beneficial effect on the nodule count and nodularity in these sections. Nodularity was below 80% in section thicknesses of 38, 50, 75 and 100 mm when Bi was not added. Detrimental effect of RE elements on graphite morphology in these sections was neutralized by adequate addition of Bi. Addition of 0.001 wt.% Bi (ratio of RE/Bi = 3.27) was enough to achieve nodularity above 80% in the section thickness of 38 mm. Nodularity was increased above 80% in section thicknesses of 50, 75 and 100 mm by addition of 0.0042 wt.% Bi (ratio of RE/Bi = 0.78). At the same time, Bi significantly increased the nodule count. Nodularity above 80% and the high nodule count in the section thicknesses of 75 and 100 mm were also achieved by using an external metallic chill in the mold. In this case, addition of Bi was not required.
Źródło:
Archives of Metallurgy and Materials; 2018, 63, 3; 1547-1553
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Rare Earth Cerium Addition on Oxidation Behavior of Co-Al-W Alloys at 800°C
Autorzy:
Migas, Damian
Liptáková, Tatiana
Moskal, Grzegorz
Powiązania:
https://bibliotekanauki.pl/articles/2048827.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
rare earth elements
REE
cyclic oxidation
γ-γ′ cobalt-based superalloys
Co-Ce
Opis:
The γ/γ′ Co-based alloys are a new class of cobalt superalloys, which are characterized by remarkable high temperature strength owing to strengthening by γ′-Co3(Al, X) phases. In this investigation, the effect of cerium addition on oxidation behavior of model Co-Al-W alloys was studied. The introduction of Ce aimed at improvement of the oxidation resistance of γ′-forming Co-based superalloys. The minor additions of cerium (0.1, 0.5 at.%) were added to the base alloy Co-9Al-9W. The alloys were prepared via induction vacuum melting (VIM). Further, a primary microstructure of the alloys was analyzed with particular regard to a segregation of Ce. The thermogravimetric analysis (TG) under non-isothermal conditions was used to preliminary estimate the oxidation behavior of alloys at different temperatures. During experiment, differential thermal analysis (DTA) was performed simultaneously. After this test, cyclic oxidation expermients was carried out at 800°C for 500 h. In as-cast state, Ce segregates to interdendritic areas and forms intermetallic phases. The effect connected with melting of interdendritic precipitates was observed at 1160°C. Ce-containing alloys were less prone of oxide spallation. Moreover, oxidation rate of these alloys substantially decreased after 100h of oxidation, whereas mass of the sample corresponding to base alloy continued to increase.
Źródło:
Archives of Metallurgy and Materials; 2022, 67, 1; 203-208
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Active optical fibres for application in laser and broadband ASE sources
Autorzy:
Dorosz, D.
Dorosz, J.
Zając, A.
Żmojda, J.
Kochanowicz, M.
Powiązania:
https://bibliotekanauki.pl/articles/201633.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
active optical fibres
double-clad fibres
RE doped glasses
rare earth elements (REE)
Opis:
The article brings into focus the present state of technology employing active fibres doped with rare earth (RE) ions for applications requiring power supply of several dozen watts and broadband ASE sources. Current trends in development of glasses and in construction of active fibres used in fibre sources of radiation within VIS-NIR range are presented. Technological constraints in the doping of fibre core glasses are discussed, with particular consideration of optimal RE concentration for technical applications. Characteristics of glasses are offered, and the glasses are used for manufacturing optical fibres with luminescence within the visible as well as near- and mid-infrared ranges. Also, requirements and luminescence properties concerning glasses co-doped with e.g. Nd3+/Yb3+,Tm3+/Ho3+ and Yb3+/Tb3+ are discussed. Results of research on the impact of technological parameters of glass matrices on luminescence properties of core glasses and optical fibres are quoted. For the doped glasses of which luminescence in a wide spectral range is desired, conditions for their processing into optical fibre systems are mentioned. Additionally, the impact of phonon energy in the glass on producing emission in a specified spectral range is analyzed. Furthermore, the article presents directions of technological studies to solve problems persisting in the phase of glass matrix design, as well as in determining the influence of fibre drawing process on the luminescence properties of core glasses and optical fibres, confirming the differences in luminescence stemming from the drawing process. Finally, some original designs of core glasses and active multicore fibre systems devised for construction of fibre radiation sources are presented.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2012, 60, 4; 673-682
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mechanical alloying of Mg-Zn-Ca-Er alloy
Autorzy:
Hrapkowicz, Bartłomiej
Lesz, Sabina
Kremzer, Marek
Karolus, Małgorzata
Pakieła, Wojciech
Powiązania:
https://bibliotekanauki.pl/articles/2086890.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
magnesium
mechanical alloying
erbium
rare earth elements
magnez
stopowanie mechaniczne
erb
pierwiastki ziem rzadkich
Opis:
Magnesium-based materials constitute promising alternatives for medical applications, due to their characteristics, such as good mechanical and biological properties. This opens many possibilities for biodegradable materials to be used as less-invasive options for treatment. Degradation is prompted by their chemical composition and microstructure. Both those aspects can be finely adjusted by means of proper manufacturing processes, such as mechanical alloying (MA). Furthermore, MA allows for alloying elements that would normally be really hard to mix due to their very different properties. Magnesium usually needs various alloying elements, which can further increase its characteristics. Alloying magnesium with rare earth elements is considered to greatly improve the aforementioned properties. Due to that fact, erbium was used as one of the alloying elements, alongside zinc and calcium, to obtain an Mg₆₄Zn₃₀Ca₄Er₁ alloy via mechanical alloying. The alloy was milled in the SPEX 8000 Dual Mixer/Mill high energy mill under an argon atmosphere for 8, 13, and 20 hours. It was assessed using X-ray diffraction, energy dispersive spectroscopy and granulometric analysis as well as by studying its hardness. The hardness values reached 232, 250, and 302 HV, respectively, which is closely related to their particle size. Average particle sizes were 15, 16, and 17 μm, respectively.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2021, 69, 5; e137587, 1--7
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Purification And Separation Of Rare Earth Elements From CCFL With Extraction Chromatography
Oczyszczanie i separacja metali ziem rzadkich z lamp fluorescencyjnych z zimną katodą (CCFL) przy użyciu chromatografii ekstrakcji
Autorzy:
Kim, J. G.
Powiązania:
https://bibliotekanauki.pl/articles/352470.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
extraction chromatography
CCFL
rare earth elements (REE)
amberite
recycling
chromatografia ekstrakcyjna
pierwiastki ziem rzadkich
recykling
Opis:
In this study, Amberite XAD-7HP was used as the solvent-impregnated resin to separate each REE from the standard solution, which was mixed with the REEs (e.g., La Eu, Tb, Y and Ba). About 100 ppm of each of the REEs was separated from DI water using extraction chromatography. REEs were separated by extraction chromatography using Amberite XAD-7HP resin, the changes in the pH values of the HCl and HClO4 were between 0.2 N and 5 N, and the extraction rate of the solution was between 0.5 and 3 ml/min. The La solution with the separated REEs was leached. The solid-state REEs were annealed between 1083K. The extraction result was analyzed with ICP-AES and an X-ray diffractometer. Each REE was successfully separated with HCl and HClO4 with pH values between 0.1 N and 3 N and with extraction rate between 1.0 m/min and 3.0 m/min.
Źródło:
Archives of Metallurgy and Materials; 2015, 60, 2B; 1529-1533
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Microstructural Characterization of the As-cast AZ91 Magnesium Alloy with Rare Earth Elements
Autorzy:
Grzybowska, A.
Braszczyńska-Malik, K.
Powiązania:
https://bibliotekanauki.pl/articles/382210.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
Mg-Al-Zn alloy
rare earth elements
microstructure
stop Mg-AI-Zn
pierwiastki ziem rzadkich
mikrostruktura
Opis:
Microstructural analysis of as-cast Mg-9Al-0.9Zn-xRE (x = 0, 1, 2, 3, 5 wt.%) magnesium alloys is presented. Light microscopy (LM) and scanning electron microscopy (SEM+EDX) were used to characterized the obtained material. The results revealed that the as-cast AZ91 alloy consists of α – Mg matrix, binary eutectic α + γ (where γ is Mg17Al12). While rare earth elements were introduced to the Mg-Al-Zn alloy new Al11RE3 phase was formed. Additionally, in the experimental alloys instead of Al-Mn phase, ternary Al-Mn-RE compound was observed. What is more, the influence of RE addition on the area fraction of eutectic and needle-like phase was analysed. With increasing addition of RE, the amount of γ phase decreased, but the amount of Al11RE3 phase increased.
Źródło:
Archives of Foundry Engineering; 2012, 12, 2s; 23-26
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Modification of non-metallic inclusions by rare-earth elements in microalloyed steels
Autorzy:
Opiela, M.
Grajcar, A.
Powiązania:
https://bibliotekanauki.pl/articles/382841.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
pierwiastki ziem rzadkich
wtrącenia niemetaliczne
stal mikrostopowa
rare earth elements (REE)
non-metallic inclusions
microalloyed steels
Opis:
The modification of the chemical composition of non-metallic inclusions by rare-earth elements in the new-developed microalloyed steels was discussed in the paper. The investigated steels are assigned to production of forged elements by thermomechanical treatment. The steels were melted in a vaccum induction furnace and modification of non-metallic inclusions was carried out by the michmetal in the amount of 2.0 g per 1 kg of steel. It was found that using material charge of high purity and a realization of metallurgical process in vacuous conditions result in a low concentration of sulfur (0.004%), phosphorus (from 0.006 to 0.008%) and oxygen (6 ppm). The high metallurgical purity is confirmed by a small fraction of non-metallic inclusions averaging 0.075%. A large majority of non-metallic inclusions are fine, globular oxide-sulfide or sulfide particles with a mean size 17 m2. The chemical composition and morphology of non-metallic inclusions was modified by Ce, La and Nd, what results a small deformability of nonmetallic inclusions during hot-working.
Źródło:
Archives of Foundry Engineering; 2012, 12, 2; 129-134
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Some Mechanical Properties of Experimental Mg-Al-RE-Mn Magnesium Alloys
Autorzy:
Braszczyńska-Malik, K.N.
Powiązania:
https://bibliotekanauki.pl/articles/379996.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
magnesium alloy
aluminum
rare earth elements (REE)
mechanical properties
stop magnezu
aluminium
pierwiastki ziem rzadkich
właściwości mechaniczne
Opis:
The results of some mechanical properties of four Mg-5Al-xRE-0.4Mn (x=1–5) alloys are presented. The microstructure of experimental alloys consisted of an σ-Mg phase and an α+γ semi-divorced eutectic, Al11 RE3 phase and an Al10 RE2 Mn7 intermetallic compound. For gravity casting in metal mould alloys, Brinell hardness, impact strength, tensile and compression properties at ambient temperature were determined. The performed mechanical tests allowed the author to determine the proportional influence of the mass fraction of rare earth elements in the alloys on their tensile strength, yield strength, compression strength and Brinell hardness. The impact strength of the alloys slightly decreases with a rise in the rare earth elements mass fraction.
Źródło:
Archives of Foundry Engineering; 2014, 14, 1; 13-16
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Rare earth elements of orzeskie beds of south-west part Upper Silesian Coal Basin (Poland)
Pierwiastki ziem rzadkich z pokładów węgla warstw orzeskich południowo-zachodniej części GZW (Polska)
Autorzy:
Adamczyk, Z.
Białecka, B.
Całusz Moszko, J.
Komorek, J.
Lewandowska, M.
Powiązania:
https://bibliotekanauki.pl/articles/219118.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
rare earth elements (REE)
coal
Orzesze beds
USCB
pierwiastki ziem rzadkich (REE)
węgiel kamienny
warstwy orzeskie
GZW
Opis:
The subject of the research concerned the coal samples from 360/1, 361 and 362/1 seams of the Orzesze beds in the “Pniówek” coal mine. The obtained samples were characterized by low ash content – 2.22-6.27% of the mass. The chemical composition of the ash indicates the presence of aluminosilicate minerale in the analyzed coal samples – most likely clay minerals, the presence of which has been confirmed In microscopic tests of the petrographic composition of channel samples of coal. The content of rare earth elements (REE sum) in the ash of the tested coal seams ranged from 364 to 1429 ppm. Variation of the REE content has been observed within a single seam. The fraction of REE indicates a relation with a mineral substance. No relation of the REE fraction and the presence of red beds has been found based on the tested samples. The content of REE found in ash, normalized to chondrites, is characterized by LREE enrichment in relation to HREE. The Eu anomaly is most likely related to tuff and tonstein levels occurring in Orzesze beds, which accompany the coal seams in the Upper Silesian Coal Basin (i.a., south of the studied area). The research has indicated that LREE in the tested samples are more related to the mineral substance, while HREE have a stronger affinity with organic substances.
Przedmiotem badań były próbki węgla z pokładów 360/1, 361 i 362/1 warstw orzeskich KWK Pniówek. Próbki te charakteryzują się niewielką zawartością popiołu 2,22-6,27% mas. Skład chemiczny popiołów wskazuje na obecność w analizowanych próbkach węgla minerałów z grupy glinokrzemianów najprawdopodobniej minerałów ilastych, których obecność była stwierdzona w badaniach mikroskopowych składu petrograficznego próbek bruzdowych węgla. Zawartości pierwiastków ziem rzadkich (suma REE) w popiołach badanych pokładów węgla wahają się od 364 do 1429 ppm. Obserwuje się zróżnicowanie zawartości REE w obrębie jednego pokładu. Udział REE wykazuje związek z substancją mineralną. Nie stwierdzono związku udziału REE, w badanych próbkach, z obecnością utworów pstrych w stropie karbonu. Zawartości REE oznaczone w popiołach, znormalizowane do chondrytów, charakteryzują się wzbogaceniem LREE wobec HREE. Anomalia Eu związana jest prawdopodobnie z występującymi w warstwach orzeskich (m.in. na północ od obszaru badań) Górnośląskiego Zagłębia Węglowego poziomami tufów i tonsteinów, które towarzyszą pokładom węgla. Badania wykazały, że LREE w badanych próbkach związane są raczej z substancją mineralną, natomiast HREE posiadają silniejsze powinowactwo z substancją organiczną.
Źródło:
Archives of Mining Sciences; 2015, 60, 1; 157-172
0860-7001
Pojawia się w:
Archives of Mining Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Microstructure of Mg–Al–RE-type Experimental Magnesium Alloy Gravity Cast into Sand Mould
Autorzy:
Braszczyńska-Malik, K. N.
Przełożyńska, E.
Powiązania:
https://bibliotekanauki.pl/articles/379591.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
magnesium alloy
aluminium
rare earth elements (REE)
as-cast conditions
microstructure
stop magnezu
pierwiastki ziem rzadkich
odlew
mikrostruktura
Opis:
Magnesium alloy with 5 wt% Al, 0.35 wt% Mn and 5 wt% rare earth elements (RE) was prepared and gravity cast into a sand mould. Microstructure investigations were conducted. Analyses of the Mg-Al-RE alloy microstructure were carried out by light microscopy, scanning electron microscopy and the XRD technique. In the as-cast condition, the alloy was composed of α-Mg, Al11RE3 and Al10RE2Mn7 intermetallic phases. Additionally, due to non-equilibrium solidification conditions, an Al2RE intermetallic phase was revealed.
Źródło:
Archives of Foundry Engineering; 2016, 16, 2; 115-118
1897-3310
2299-2944
Pojawia się w:
Archives of Foundry Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The impact of a Neogene basaltoid intrusion on the distribution of rare earth elements and yttrium in Carboniferous rocks from the Sumina area, Poland (SW part of Upper Silesian Coal Basin)
Autorzy:
Adamczyk, Zdzisław
Komorek, Joanna
Nowak, Jacek
Lewandowska, Małgorzata
Powiązania:
https://bibliotekanauki.pl/articles/139034.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
rare earth elements
Rare earth yttrium (REY)
neogene basaltoid intrusion
Upper Silesian Coal Basin (USCB)
pierwiastki ziem rzadkich
neogen
bazaltoidy
Górnośląskie Zagłębie Węglowe (GZW)
Opis:
The Neogene basaltoid intrusions found in the S-7 borehole in the Sumina area (USCB) caused transformations of the adjacent Carboniferous rocks. The mineral and chemical compositions of the basaltoides are similar to those of the Lower Silesian basaltoides. The transformations that took place in the vicinity of the intrusion were manifested in the formation of natural coke, the secondary mineralization of these rocks (calcite, chlorite, zeolites and barite) and in the specific distribution of rare earths (REY). Among REY, the light elements (LREY) had the highest share, while the heavy elements (HREY) had the lowest share. Regardless of the lithological type of the analyzed rock, with increasing distance from the intrusion, the percentage of MREY and HREY elements increases at the expense of the light elements LREY. All analyzed distribution patterns of the REYs are characterized by the occurrence of anomalies, which often show a significant correlation with the distance of sampling points from the basaltoid intrusion. The specific distribution of REYs in the vicinity of the intrusion of igneous rocks is an indication of the impact of hydrothermal solutions associated with the presence of basaltoides on the rocks closest to them located at a temperature of over 200°C
Źródło:
Acta Geologica Polonica; 2020, 70, 1; 31-49
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Changes in the concentration of some rare earth elements in coal waste
Zmiany koncentracji wybranych pierwiastków ziem rzadkich (REEs) w odpadach węglowych
Autorzy:
Nowak, J.
Kokowska-Pawłowska, M.
Powiązania:
https://bibliotekanauki.pl/articles/219130.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
pierwiastki ziem rzadkich (REEs)
odpady górnicze
odpady powęglowe
przeobrażenia termiczne
rare earth elements (REE)
post mining wastes
coal wastes
thermal transformations
Opis:
Coal waste is formed during coal mining and processing operations. That waste comprises mainly sedimentary rocks that occur in roofs and floors of underground workings and in partings in coal seams. It contains numerous trace elements, including rare earth elements (REEs). Hypergenic processes that take place in coal waste piles may lead to endogenous fires. Thermal transformations of waste have an effect on changes in its phase and chemical composition, including the concentration of trace elements. The paper presents changes in the content of selected rare earth elements (Sc, Y, La, Ce, Nd, Sm, Eu, Tb, Yb, Lu) in wastes of varying degree of thermal transformation. The results of REE content determination in lump samples were subjected to statistical analysis and coefficients of correlation between the studied rare earth elements and the main chemical constituents were determined. The primary carriers of REEs in coal waste are clay minerals. Phase transformations that take place at high temperatures (including dehydroxylation of clay minerals and formation of minerals characteristic of contact metamorphism) cause changes in the concentration of rare earth elements.
Odpady powęglowe powstają w wyniku eksploatacji oraz przeróbki węgla kamiennego. Są to głównie skały osadowe występujące w stropach i spągach oraz przerostach pokładów węgla. Odpady te zawierają liczne pierwiastki śladowe, w tym pierwiastki ziem rzadkich (REEs). Procesy hipergeniczne zachodzące na zwałowiskach odpadów powęglowych mogą prowadzić do powstawania pożarów endogenicznych. Przeobrażenia termiczne odpadów wpływają na zmiany ich składu fazowego i chemicznego, w tym koncentracji pierwiastków śladowych. W artykule przedstawiono zmiany zawartości wybranych pierwiastków ziem rzadkich (Sc, Y, La, Ce, Nd, Sm, Eu, Tb, Yb, Lu ) w odpadach o różnym stopniu termicznego przeobrażenia. Wyniki oznaczeń zawartości REEs w próbkach kawałkowych poddano analizie statystycznej i wyznaczono współczynniki korelacji pomiędzy badanymi pierwiastkami ziem rzadkich a głównymi składnikami chemicznymi. Pierwotnym nośnikiem REEs w odpadach powęglowych są minerały ilaste. Przeobrażenia fazowe zachodzące pod wpływem wysokiej temperatury (w tym dehydroksylacja minerałów ilastych i tworzenia się minerałów charakterystycznych dla metamorfizmu kontaktowego) powodują zmiany koncentracji pierwiastków ziem rzadkich.
Źródło:
Archives of Mining Sciences; 2017, 62, 3; 495-507
0860-7001
Pojawia się w:
Archives of Mining Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Stability relationships of REE-bearing phosphates in an alkali-rich system (nepheline syenite from the Mariupol Massif, SE Ukraine)
Autorzy:
Dumańska-Słowik, M.
Budzyń, B.
Heflik, W.
Sikorska, M.
Powiązania:
https://bibliotekanauki.pl/articles/138608.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
fluorowy apaty
mariupolit
monacyt
pierwiastki ziem rzadkich
ponowne wytrącanie
rozpuszczanie
Ukraina
dissolution-reprecipitation
fluorapatite
fluorbritholite
Mariupolite
monazite
rare earth elements (REE)
Ukraine
Opis:
Primary REE-enriched fluorapatite and fluorbritholite-(Ce) in nepheline syenite from the Mariupol Massif (SE Ukraine), contain textural and chemical evidence of late- to post-magmatic metasomatic alteration. REE mobilization and replacement of the primary phases by fluid-mediated coupled dissolution-reprecipitation strongly depended on the distance between the altered minerals in the host rock. Fluorapatite and fluorbritholite-(Ce) forming individual pristine grains were partially replaced by the same phase with a new composition, resulting in the presence of patchy zoning in altered grains. the increased REE contents in altered fluorapatite rim domains are related to REE mobilization from the altered REE-depleted rim domains of the fluorbritholite-(Ce). The REEs were transported by a fluid with high F activity. The alteration of fluorapatite and fluorbritholite-(Ce) grains in contact resulted in the partial replacement of the primary phases by the same phase with a new composition, but also in the partial replacement of the fluorapatite by secondary monazite and fluorite. The REE mobilized from the fluorbritholite-(Ce) in the presence of a F-rich fluid in an alkali-rich system promoted formation of monazite as the new phosphate REE-host. The presence of secondary parisite in the altered domains of the fluorapatite and fluorbritholite-(Ce) indicates a CO2 component in the fluid during metasomatic alteration.
Źródło:
Acta Geologica Polonica; 2012, 62, 2; 247-265
0001-5709
Pojawia się w:
Acta Geologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Recovery Of Electrodic Powder From Spent Nickel-Metal Hydride Batteries (NiMH)
Odzyskiwanie proszku elektrodowego ze zużytych akumulatorów niklowo-wodorkowych (NiMH)
Autorzy:
Shin, S. M.
Shin, D. J.
Jung, G. J.
Kim, Y. H.
Wang, J. P.
Powiązania:
https://bibliotekanauki.pl/articles/356110.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
nickel-metal hybride (NiMH)
electrodic powder
nickel
rare earth elements (REE)
thermal treatment
akumulator niklowo-wodorkowy
proszek elektrodowy
nikiel
pierwiastki ziem rzadkich
obróbka termiczna
Opis:
This study was focused on recycling process newly proposed to recover electrodic powder enriched in nickel (Ni) and rare earth elements (La and Ce) from spent nickel-metal hydride batteries (NiMH). In addition, this new process was designed to prevent explosion of batteries during thermal treatment under inert atmosphere. Spent nickel metal hydride batteries were heated over range of 300°C to 600°C for 2 hours and each component was completely separated inside reactor after experiment. Electrodic powder was successfully recovered from bulk components containing several pieces of metals through sieving operation. The electrodic powder obtained was examined by X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDX) and image of the powder was taken by scanning electron microscopy (SEM). It was finally found that nickel and rare earth elements were mainly recovered to about 45 wt.% and 12 wt.% in electrodic powder, respectively.
Źródło:
Archives of Metallurgy and Materials; 2015, 60, 2B; 1139-1143
1733-3490
Pojawia się w:
Archives of Metallurgy and Materials
Dostawca treści:
Biblioteka Nauki
Artykuł
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