Molecular insight into the mode-of-action of phosphonate monolayers as active functions of hybrid metal oxide adsorbents. Case study in sequestration of rare earth elements

RSC Advances ◽  
2015 ◽  
Vol 5 (31) ◽  
pp. 24575-24585 ◽  
Author(s):  
Gulaim A. Seisenbaeva ◽  
Inna V. Melnyk ◽  
Niklas Hedin ◽  
Yang Chen ◽  
Philip Eriksson ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Phosphonic Acid ◽  
Molecular Model ◽  
Model Compounds ◽  
Inorganic Hybrid ◽  
X Ray ◽  
Hybrid Metal Oxide ◽  
Insight Into

Organic–inorganic hybrid adsorbents for separation of rare earth elements were prepared by grafting of amino phosphonic acid ligands onto mesoporous TiO2. Their structure and capacity were elucidated using X-ray studies of molecular model compounds.

KSeries X-Ray Wavelengths in Rare Earth Elements

1958 ◽  
Vol 112 (4) ◽  
pp. 1183-1186 ◽  
Author(s):  
E. L. Chupp ◽  
J. W. M. Du Mond ◽  
F. J. Gordon ◽  
R. C. Jopson ◽  
Hans Mark
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
X Ray

Structure Maps and Phase Stability in AlTi3 Alloyed with Rare-Earth Elements

1988 ◽  
Vol 133 ◽  
Author(s):  
C. T. Liu ◽  
J. A. Horton ◽  
D. G. Petitifor
Keyword(s):  
Crystal Structure ◽  
Rare Earth ◽  
Rare Earth Elements ◽  
Solubility Limit ◽  
Size Factor ◽  
X Ray Diffraction ◽  
Atomic Size ◽  
X Ray ◽  
Dependent Parameter ◽  
Rare Earth Additions

ABSTRACTRare-earth elements including Y, Er and Sc were added to AlTi3 for stabilizing the Ll2 ordered crystal structure, as predicted by the AB3 structure map. The crystal structure and phase composition in the AlTi3 alloys were studied by electron microprobe analysis, X-ray diffraction and TEM. The solubility limit of the rare-earth elements were determined and correlated with the atomic size factor. The results obtained so far indicate that rare-earth additions are unable to change the crystal structure of AlTi3 from DO19 to Ll2. The inability to stabilize the Ll2 structure demonstrates the need to characterize the structure map domains with a further period-dependent parameter.

Affinity of dual energy X-ray transmission sensors on minerals bearing heavy rare earth elements

2020 ◽  
Vol 147 ◽  
pp. 106151 ◽  
Author(s):  
Moacir Medeiros Veras ◽  
Aaron Samuel Young ◽  
Cristiano Rocha Born ◽  
Artur Szewczuk ◽  
Artur Cezar Bastos Neto ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Dual Energy ◽  
Heavy Rare Earth ◽  
X Ray ◽  
Heavy Rare Earth Elements

scholarly journals Hydrothermal Synthesis of Rare-Earth Modified Titania: Influence on Phase Composition, Optical Properties, and Photocatalytic Activity

Materials ◽  
2019 ◽  
Vol 12 (5) ◽  
pp. 713 ◽  
Author(s):  
Nejc Rozman ◽  
David Tobaldi ◽  
Uroš Cvelbar ◽  
Harinarayanan Puliyalil ◽  
João Labrincha ◽  
...  
Keyword(s):  
Optical Properties ◽  
Photocatalytic Activity ◽  
Rare Earth ◽  
Hydrothermal Synthesis ◽  
Rare Earth Elements ◽  
Rare Earths ◽  
Light Absorption ◽  
Pure Tio2 ◽  
X Ray ◽  
Hydroxyl Oxygen

In order to expand the use of titania indoor as well as to increase its overall performance, narrowing the band gap is one of the possibilities to achieve this. Modifying with rare earths (REs) has been relatively unexplored, especially the modification of rutile with rare earth cations. The aim of this study was to find the influence of the modification of TiO2 with rare earths on its structural, optical, morphological, and photocatalytic properties. Titania was synthesized using TiOSO4 as the source of titanium via hydrothermal synthesis procedure at low temperature (200 °C) and modified with selected rare earth elements, namely, Ce, La, and Gd. Structural properties of samples were determined by X-ray powder diffraction (XRD), and the phase ratio was calculated using the Rietveld method. Optical properties were analyzed by ultraviolet and visible light (UV-Vis) spectroscopy. Field emission scanning electron microscope (FE-SEM) was used to determine the morphological properties of samples and to estimate the size of primary crystals. X-ray photoelectron spectroscopy (XPS) was used to determine the chemical bonding properties of samples. Photocatalytic activity of the prepared photocatalysts as well as the titania available on the market (P25) was measured in three different setups, assessing volatile organic compound (VOC) degradation, NOx abatement, and water purification. It was found out that modification with rare earth elements slows down the transformation of anatase and brookite to rutile. Whereas the unmodified sample was composed of only rutile, La- and Gd-modified samples contained anatase and rutile, and Ce-modified samples consisted of anatase, brookite, and rutile. Modification with rare earth metals has turned out to be detrimental to photocatalytic activity. In all cases, pure TiO2 outperformed the modified samples. Cerium-modified TiO2 was the least active sample, despite having a light absorption tail up to 585 nm wavelength. La- and Gd-modified samples did not show a significant shift in light absorption when compared to the pure TiO2 sample. The reason for the lower activity of modified samples was attributed to a greater Ti3+/Ti4+ ratio and a large amount of hydroxyl oxygen found in pure TiO2. All the modified samples had a smaller Ti3+/Ti4+ ratio and less hydroxyl oxygen.

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