STERIC EFFECTS IN THE SYNERGIC EXTRACTION OF THE LANTHANIDES, YTTRIUM, AND SCANDIUM

1963 ◽  
Vol 41 (3) ◽  
pp. 658-666 ◽  
Author(s):  
P. G. Manning
Keyword(s):  
Rare Earth ◽  
Metal Ion ◽  
Equilibrium Constants ◽  
Rare Earth Metals ◽  
Steric Effects ◽  
Organic Species ◽  
Alkyl Groups ◽  
Synergic Extraction ◽  
Carrier Free ◽  
Organic Solutions

From a study of the partitioning of the carrier-free radioisotopes Tm170, Ce144, Eu152/154, Tb160, Lu177, and Y91 between nitric acid and organic solutions containing various proportions of thenoyltrifluoroacetone (HTTA) and dialkyl alkyl phosphonates (S) in odorless kerosene, concentration equilibrium constants (k2) have been computed for the reaction[Formula: see text]where M represents a metal ion, and "w" and "o" are aqueous and organic species respectively.When used in conjunction with the data of Bronaugh and Suttle, the equilibrium constants determined in this study yielded comparative equilibrium constants (k3) for the solvation process [Formula: see text]for the rare-earth metals listed.In the extraction of Sc46, however, the species extracted is dependent on the alkyl groups of the phosphonates, the butyl and 2-ethylhexyl derivatives giving mono- and di-solvates respectively.It is concluded that steric effects are dominant in these synergic systems.

THERMODYNAMICS OF THE PROCESSES OF INTERACTION OF LIQUID METAL COMPONENTS IN Fe – Mg – Al – La – O SYSTEM

2018 ◽  
Vol 61 (6) ◽  
pp. 460-465
Author(s):  
G. G. Mikhailov ◽  
L. A. Makrovets ◽  
L. A. Smirnov
Keyword(s):  
Rare Earth ◽  
Liquid Metal ◽  
Rare Earth Elements ◽  
Phase Equilibria ◽  
Thermodynamic Modeling ◽  
Equilibrium Constants ◽  
Rare Earth Metals ◽  
Oxide Systems ◽  
Metal Melts ◽  
Steel Deoxidation

At the present time, rare-earth elements in metallurgy are used in  the form of mischmetal – a rare-earth elements natural mixture (with  atomic numbers from 57 to 71). It contains about 50  wt.  % of cerium.  The remaining elements are mainly lanthanum and niobium. The specific composition is determined by the ore deposit. Inconstant composition of the modifier containing rare-earth metals (REM) can significantly reduce its efficiency. Experimentally, for every branded steels  composition the ratio of various REMs can’t be selected because of the  high costs of obtaining technically pure rare-earth metals. The task of  determining the each rare earth element optimum concentrations and  complex ligature composition can be solved by thermodynamic modeling. In the framework of thermodynamic modeling, the interaction  between magnesium, aluminum and lanthanum with oxygen in liquid  iron is presented. And the thermodynamic model of steel deoxidation  by these active metals composition is considered. On the basis of available literature data on the phase diagrams of the systems MgO – Al2O3 ,  MgO – La2O3 and La2O3 – Al2O3 , the coordinates of the invariant equilibria points in the system MgO – La2O3 – Al2O3 were determined. The  phase diagram of the system MgO – La2O3 – Al2O3 was constructed. It  made possible to establish all phase equilibria realized in the process  of deoxidation of steel with magnesium, lanthanum and aluminum and  to describe these phase equilibria by chemical reactions equations. The  activity of the components in liquid oxide melts was determined using  the theory of subregular ionic solutions, which takes into account the  dependence of the coordination number of cations on the composition  of the oxide melt. The activity of components in metal melts conjugated with oxide systems were determined by Wagner’s theory using the  parameters of the first order interaction. Equilibrium constants values  for the steel deoxidation reactions are installed indirectly by thermodynamic calculations. On the basis of the obtained data the components  solubility surface in the metal melts of Fe – Mg – Al – La – O system  was constructed, which allowed to determine the liquid metal composition regions associated with the corresponding oxide phase.

scholarly journals Ionic Liquids Based on the Concept of Melting Point Lowering Due to Ethoxylation

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 4034
Author(s):  
Manuel Rothe ◽  
Eva Müller ◽  
Patrick Denk ◽  
Werner Kunz
Keyword(s):  
Ionic Liquids ◽  
Rare Earth ◽  
Melting Point ◽  
Metal Ion ◽  
Rare Earth Metals ◽  
Metal Catalysis ◽  
Alkyl Chains ◽  
Metal Organic ◽  
Surface Active ◽  
The Common

Most of the commonly used Ionic Liquids (ILs) contain bulky organic cations with suitable anions. With our COMPLET (Concept of Melting Point Lowering due to Ethoxylation), we follow a different approach. We use simple, low-toxic, cheap, and commercially available anions of the type Cx(EO)yCH2COO– to liquefy presumably any simple metal ion, independently of its charge. In the simplest case, the cation can be sodium or lithium, but synthesis of Ionic Liquids is also possible with cations of higher valences such as transition or rare earth metals. Anions with longer alkyl chains are surface active and form surface active ionic liquids (SAILs), which combine properties of ionic and nonionic surfactants at room temperature. They show significant structuring even in their pure state, i.e., in the absence of water or any other added solvent. This approach offers new application domains that go far beyond the common real or hypothetical use of classical Ionic Liquids. Possible applications include the separation of rare earth metals, the use as interesting media for metal catalysis, or the synthesis of completely new materials (for example, in analogy to metal organic frameworks).

Magnetic susceptibility of liquid heavy rare earth metals

1979 ◽  
Vol 40 (C5) ◽  
pp. C5-260-C5-261 ◽  
Author(s):  
M. Müller ◽  
E. Huber ◽  
H.-J. Güntherodt
Keyword(s):  
Magnetic Susceptibility ◽  
Rare Earth ◽  
Rare Earth Metals ◽  
Heavy Rare Earth

ELECTRONIC RELAXATION IN RARE EARTH METALS AND ALLOYS - A NON-KRAMERS EXAMPLE : Tm3+

1980 ◽  
Vol 41 (C1) ◽  
pp. C1-25-C1-31 ◽  
Author(s):  
N. S. Dixon ◽  
L. S. Fritz ◽  
Y. Mahmud ◽  
B. B. Triplett ◽  
S. S. Hanna ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Metals ◽  
Metals And Alloys ◽  
Electronic Relaxation

Leaching of Rare Earth Metals from Manganese Nodule by HCl Solution

2015 ◽  
Vol 53 (9) ◽  
pp. 637-641
Author(s):  
Chul-Woo Nam ◽  
Kyung-Ho Park ◽  
Hyun-Ho Kim ◽  
Jin-Tae Park
Keyword(s):  
Rare Earth ◽  
Rare Earth Metals ◽  
Manganese Nodule ◽  
Hcl Solution

Physico-chemical properties of the rare-earth metals, scandium, and yttrium

1963 ◽  
Vol 79 (2) ◽  
pp. 263-293 ◽  
Author(s):  
E.M. Savitskii ◽  
V.F. Terekhova ◽  
O.P. Naumkin
Keyword(s):  
Rare Earth ◽  
Rare Earth Metals ◽  
Chemical Properties ◽  
Physico Chemical ◽  
The Rare Earth

Ferromagnetism and antiferromagnetism of rare-earth metals

1964 ◽  
Vol 82 (3) ◽  
pp. 449-498 ◽  
Author(s):  
Konstantin P. Belov ◽  
R.Z. Levitin ◽  
S.A. Nikitin
Keyword(s):  
Rare Earth ◽  
Rare Earth Metals
Sign in / Sign up

Export Citation Format

Share Document