Extraction of REE(III), U(VI), and Th(IV) from Perchlorate Solutions with Tetraphenyl(o-oxyphenylenemethylene)diphosphine Dioxide

Radiochemistry - The extraction of microamounts of REE(III), U(VI), and Th(IV) from perchlorate solutions with solutions of tetraphenyl(o-oxyphenylenemethylene)diphosphine dioxide (I) in...     

Influence of the Structure of (О-Phenylenoxymethylene)diphosphine Dioxides on Their Extraction Ability to U(VI), Th(IV), and REE(III) in Nitric Acid Media

Radiochemistry - Extraction of microquantites of U(VI), Th(IV), and REE(III) from nitric acid solutions with solutions of (o-phenyleneoxymethylene)diphosphine dioxides with phenyl and butyl...     

Magnesium Octa[(4'-Benzo-15-Crown-5)-Oxy]Phthalocyaninate in Low-Molecular Hydrogels: Spectral Properties and Release under Stimulation

This work is dedicated to low-molecular hydrogels based on biodegradable sodium deoxycholate (SDC) and lysine hydrochloride (lys × HCl) with magnesium octa-[(4'-benzo-15-crown-5)-oxy]phthalocyaninate (Mgcr₈Pc) as the active component, namely, their synthesis, spectral properties of gel-solubilized Mgcr₈Pc, its release from the gel etc. Addition of Mgcr₈Pc occurs both via the mixing of the components and via its diffusion from the aqueous solution into the phase of the formed SDC/lys × HCl gel. Mgcr₈Pc-containing hydrogels are thermoreversible. The state of Mgcr₈Pc in the SDC/lys × HCl/NaCl gel at the room temperature and in the melt is studied using spectral methods. Gel melting releases Mgcr₈Pc in the form of a micelle-bound monomer. The presence of the Mgcr₈Pc monomer phase in the phthalocyanine-carrying supramolecular hydrogel causes fluorescent activity of the latter.     

IPEC Solver: Numerical simulation tool to study inter-polyelectrolyte complexation

IPEC Solver is a Windows program designed to analyze the stability of core–shell inter-polyelectrolyte complexes formed by complexation of oppositely charged block copolymers. The two-dimensional size distribution of the complexes composed by different numbers of positively or negatively charged polyelectrolytes is calculated based on the scaling model of block copolymer aggregation and Poisson–Boltzmann theory for electrostatic interactions [V.A. Baulin, E. Trizac, Self-assembly of spherical inter-polyelectrolyte complexes from oppositely charged polymers, Soft Matter 8 (25) (2012) 6755–6766]. Salt effects, charge distribution and distributions of labile cations and anions around the complexes are calculated numerically as a function of chain composition and solvent properties.     

Extraction of Rare-Earth Elements from Nitric Acid Solutions with Bidentate Phosphoryl-containing Compounds and Their Mixtures

Extraction of microamounts of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu from HNO₃ solutions with neutral bidentate phosphoryl-containing compounds was studied. Extraction with tetraphenylmethylenediphosphine dioxide increases in going from Lu to La, and extraction with methyleneoxyphenyldiphosphine dioxides increases in the opposite direction. The anomalous aryl strengthening effect varies in the same direction. Extraction with mixtures of diphosphine dioxides allows efficient concentration of the sum of rare-earth elements from nitric acid solutions.     

EXTRACTION OF RARE-EARTH ELEMENTS FROM NITRIC SOLUTIONS BY PHOSPHORYL-CONTAINING PODANDS

ABSTRACT

The extraction of microquantities of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Y from HNO₃ solutions by phosphoryl-containing podands of various structures has been studied. It has been found that the maximum extraction of rare earth elements is exhibited by reagents containing one ether oxygen atom in the molecule, bound to diphenylphosphoryl or ditolylphosphoryl containing podands towards REE varies in a wide range, depending on the number of oxygen atoms in the polyether chain and the structure of the fragment connecting the ether oxygen atom with the terminal PO group. The podand structure which ensures a polydentate coordination of the reagent molecule to yield chelate complexes is favourable for REE extraction. The replacement of phenyl radicals in the podand VII molecule for butyl ones (compound IX) drastically reduces REE extraction. REE extraction by podands VII and VII increase from La to Lu with a decrease in the radii of extracted ions     

Extraction of Am(III) from Nitric Acid Solutions with Bis(diphenylphosphinylmethyl)phosphinic Acid

Extraction of trace quantities of Am(III) from aqueous HNO₃ solutions with solutions of bis(diphenylphosphinylmethyl)phosphinic acid (I), bis[2-(diphenylphosphinyl)phenoxymethyl]phosphinic acid (II), and bis[2-(diphenylphosphinylmethyl)phenoxymethyl]phosphinic acid (III) in dichloroethane was studied. The stoichiometry of the extractable complexes was determined; the effect of organic diluent on the extraction was considered. The extractive power of the reagents toward Am(III) grows in the order III < II < I. Acid I surpasses in the extractive power a neutral bidentate extractant, tetraphenylmethylenediphosphine dioxide (TPMDPD), by three orders of magnitude. A synergistic effect in extraction of Am with mixtures of TPMDPD and acid I was revealed.     

Acidic phosphoryl podands as components of extraction chromatography material for selective extraction of promethium-147

A number of new acidic phosphoryl podands with different substituents in the phosphoryl groups and different polyether chain structure are synthesized. They are used to obtain impregnation-type sorbents. A copolymer of styrene and divinyl benzene (LPS-500 grade) is used as a matrix for sorbent manufacturing. The effect of the structure and amount of supported phosphoryl podand, as well as of the concentration and nature of the acid in the initial solution of rare metals on extraction-chromatographic separation of La³⁺, Nd₃₊, Pm₃₊, and Sm₃₊ in the dynamic mode, is studied. It is found that the developed sorbents are superior with regard to efficiency of separation of these elements from weakly acidic media to the known counterparts synthesized on the basis of the conventionally used extractants: di(2-ethylhexyl)phosphoric acid and N,N,N′,N′-tetra-n-octyldiglycolamide. The possibility of practical application of the obtained sorbents for selective extraction and purification of promethium-147 from a number of associated rare-earth metals from technological solutions of PO Mayak is shown.     

Phase recrystallization of titanium and its alloys during rapid heating

NIAT. Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 2, pp. 33–36, February, 1993.