G. V. Myasoedova

Sorption Preconcentration in Combined Methods for the Determination of Noble Metals

Combined methods for the determination of noble metals with the use of sorption preconcentration with complexing, anion-exchange, and other sorbents are reviewed. Characteristics of sorbents, techniques of sorption preconcentration, and techniques for the preparation of a concentrate for determination are considered. Features of instrumental methods for the determination of noble metals in the analysis of different materials are discussed. Examples of the use of sorption preconcentration in combined methods for the determination of noble metals are given from publications between 1996–2005.

Solid-phase extractants for radionuclide preconcentration and separation. New possibilities

A review of solid-phase extractants for radionuclide preconcentration and separation is presented. Examples of solid-phase extractants prepared by impregnation of various supports with compounds used in liquid extraction are considered. The possibilities of using carbon nanotubes and ionic liquids for preparing new solid-phase extractants are discussed. Experimental data on sorption recovery of actinides, europium, and palladium from nitric acid solutions with solid-phase extractants prepared by impregnation of carbon nanotubes and polymeric supports with ionic liquids and ligands are presented.

Preconcentration of noble metals with the POLYORGS 4 complexing sorbent under the action of microwave irradiation

The sorption of Au(III), Pd(II), Pt(IV), Rh(III), and Ir(IV) with the POLYORGS 4 complexing sorbent in the static mode was studied at room temperature and on thermal and microwave heating. It was demonstrated that the sorption of noble metals from 1 M HCl and 1 M HNO3 solutions can be substantially accelerated under the action of microwave irradiation. Based on the obtained data, the conditions of the group preconcentration of noble metals for their subsequent determination by the ETAAS and ICP AES methods were selected. The preconcentration procedure was used for the analysis of certified reference material SARM-7B (platinum-containing ore), VT-1 (copper-nickel sulfide ore), and the alloy of copper with noble metals.

Simple route to secondary amides of phosphorylacetic acids and their use for extraction and sorption of actinides from nitric acid solutions

An efficient method for the synthesis of secondary alkylamides of phosphorylacetic acids (APA) was proposed. The method involves amidation of ethyl phosphorylacetates with primary aliphatic amines. The scope of reaction was determined. Reactions with ethylenediamine and 1,4-diaminobutane yield the corresponding bisamides; in the case of 1,3-diaminopropane, N-(3-aminopropyl)diphenylphosphorylacetamide or N,N′-propylenebis(diphenylphosphorylacetamide) was obtained, depending on the reaction conditions. The extraction of americium(III) complexes and the sorption of uranium(VI) by sorbents with physically sorbed APA from nitric acid solutions were studied. There is no correlation between the partition coefficient of americium(III) and the structure of APA; in the sorption of uranium(VI), the degree of extraction depends on the complexone structure.

Solid extractants prepared with ionic liquids and their use for recovery of actinides from nitric acid solutions

Solid extractants were prepared by noncovalent immobilization of phosphonium ionic liquids (ILs) on various polymeric materials, including fibrous materials. These sorption materials can be used for recovering Pu from 0.5–5 M HNO3. Immobilization of phosphorus-containing ligands on solid supports using phosphonium ILs yields a material recovering actinides from nitric acid solutions.

New solid extractants for preconcentrating noble metals

New solid extractants are synthesized with the use of imidazolium and phosphonium ionic liquids for preconcentrating noble metals. Ionic liquids are selected and conditions for their immobilization on various solid matrices are found. The adsorption properties of the synthesized solid extractants for platinum(IV) in hydrochloric acid solutions are studied. The solid extractants obtained by binding 1-hexadecyl-3-methylimidazolium bromide and trihexyltetradecylphosphonium chloride to polymeric matrices and multiwall carbon nanotubes possess good kinetic properties and selectivity in 1 M HCl, and can be used to preconcentrate Pt(IV), Pd(II), and Au(III) in combined methods of their determination.

A new combined ETAAS method for the determination of platinum, palladium, and gold traces in natural samples

A new combined method is developed for determining trace platinum, palladium, and gold in natural materials of complex composition. The method involves sorption preconcentration with solid-phase extractants obtained by impregnating polymer supports (hypercrosslinked and highly crosslinked polystyrene resins) with an imidazolium ionic liquid (1-hexadecyl-3-methylimidazolium bromide), elution with acetone under normal conditions or with a solution of thiourea in 1 M HCl under microwave heating, and the ETAAS determination of analytes in the eluate. The efficiency of the method is confirmed by the analysis of various ores and rocks.

Sorption preconcentration of radionuclides on Taunit carbon nanostructural material

The possibility of using Taunit carbon nanostructural material for sorption recovery of radionuclides from aqueous solutions was examined. Taunit efficiently recovers Am, Pu, Eu, U, and Tc from weakly acidic and neutral solutions. Taunit is a suitable support for preparing solid extractants based on a phosphonium ionic liquid and diphenyl(dibutylcarbamoylmethyl)phosphine oxide for recovery of actinides from nitric acid solutions.

Solid-phase extractants based on taunit carbon nanotubes for actinide and REE preconcentration from nitric acid solutions

The sorption properties of solid-phase extractants (SPEs) prepared by impregnation of Taunit carbon nanotubes with adducts of diphenyl(dibutylcarbamoylmethyl)phosphine oxide (CMPO) and tri-n-octylphosphine oxide (TOPO) in HNO3 solutions were studied. The SPEs exhibit high ability to sorb U(VI), Pu(IV), Np(V), Am(III), and Eu(III) from nitric acid solutions, with good kinetic properties. The impregnation conditions and distribution coefficients of the radionuclides in their recovery from 3 M HNO3 were determined. The possibility of preparing SPEs by Taunit impregnation in HNO3 solutions with adducts of tributyl phosphate (TBP) and N,N′-dimethyl-N,N′-dioctylhexylethoxymalonamide (DMDOHEMA) and with Cyphos IL-101 phosphonium ionic liquid was demonstrated.

Extraction and sorption preconcentration of U(VI), Am(III), and Pu(IV) from nitric acid solutions with alkylenediphosphine dioxides

The extraction of U(VI), Am(III), and Pu(VI) from nitric acid solutions in the form of complexes with alkylenebis(diphenylphosphine) dioxides and their sorption with POLIORGS F-6 sorbent prepared by noncovalent immobilization of methylenebis(diphenylphosphine) dioxide (MDPPD) on a KhAD-7M™ polymeric matrix were studied. The preconcentration conditions and distribution coefficients of U(VI), Am(III), and Pu(IV) in their sorption from 3 M HNO3 were determined. The possibility of concentrating actinides from multicomponent solutions was demonstrated. The composition and nature of complexes of U(VI) with MDPPD were determined from the 31P NMR data.