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Author(s): A. Yu. Sozin [sup.1] , V. A. Krylov [sup.2] , O. Yu. Chernova [sup.1] , T. G. Sorochkina [sup.1] , A. D. Bulanov [sup.1] , A. P. Kotkov [sup.3] [...], This review is devoted to the consideration of prospects and directions for the development of methods and approaches to the analysis of high-purity industrial gases and volatile hydrides, chlorides, fluorides, and organoelement compounds with natural and isotopically enriched compositions. The currently known capabilities for the determination of impurities in them using mass spectrometry, IR spectroscopy, gas chromatography, and chromatography-mass spectrometry are analyzed.

Author(s): A. Yu. Sozin [sup.1], V. A. Krylov [sup.2], O. Yu. Chernova [sup.1], T. G. Sorochkina [sup.1], A. P. Kotkov [sup.3], N. D. Grishnova [sup.3], A. I. Skosyrev [sup.3], G. [...], The review is devoted to the capabilities of gas chromatography-mass spectrometry in the analysis of high-purity volatile hydrides of naturally occurring and isotopically enriched compositions. Problems related to experimental techniques, chromatographic separation, identification, and quantitative determination of impurities are discussed. The application of this method has significantly expanded data coverage on the nature, number, and limiting possibilities of the determination of impurities in volatile inorganic hydrides. The identified impurities are compounds of various classes. Among them are atmospheric gases; saturated, unsaturated, and aromatic C.sub.1-C.sub.9 hydrocarbons; chlorine- and fluorine-containing C.sub.1-C.sub.4 hydrocarbons; homologues and alkyl derivatives of hydrides; Si.sub.2-Si.sub.4 siloxanes; fluorosiloxanes; oxygen-containing hydrocarbons; sulfur-containing substances; and hydrides of other elements. Gas chromatography-mass spectrometry analysis made it possible to detect the presence of impurities in isotopically enriched silicon and germanium hydrides, which are their molecular isobars. The use of gas chromatography-mass spectrometry in the analysis of high-purity inorganic hydrides makes it possible to reach the detection limits of impurities of 10.sup.-8-10.sup.-5 mol %.

Author(s): A. Yu. Sozin [sup.1], T. G. Sorochkina [sup.1], O. Yu. Chernova [sup.1], A. P. Kotkov [sup.2], N. D. Grishnova [sup.2], D. M. Polezhaev [sup.2], G. V. Pushkarev [sup.2], S. [...], The impurity composition of arsine is studied by gas chromatography-mass-spectrometry. Impu-rities of permanent gases; carbon dioxide; hydrides; saturated, unsaturated, and aromatic hydrocarbons C.sub.1-C.sub.6; halogenated hydrocarbons; sulfur compounds; and arsine and diarsine alkyl derivatives are determined. The impurity level of high-purity arsine is 10.sup.-6-10.sup.-5 vol %. Impurity concentrations in arsine after synthesis and in the fractions extracted in the course of its rectification are rather high and lie in the range 10.sup.-6-0.1 vol %. The limits of detection for impurities are 2 x 10.sup.-7-2 x 10.sup.-4 vol %.

Author(s): A. Yu. Sozin [sup.1], V. A. Krylov [sup.2], O. Yu. Chernova [sup.1], T. G. Sorochkina [sup.1], A. D. Bulanov [sup.1], O. Yu. Troshin [sup.1], A. P. Kotkov [sup.3], N. [...], The impurity composition of natural and isotopically enriched silane obtained from magnesium silicide and silicon tetrafluoride is studied by gas chromatography-mass-spectrometry. The impurities characteristic of silane with natural and isotopically enriched composition are atmospheric gases; carbon dioxide; hydrides; saturated, unsaturated, and aromatic hydrocarbons; halogenated hydrocarbons; alkyl derivatives and silane homologues, siloxanes. The impurity content of high-purity silane does not exceed 10.sup.-7-10.sup.-5 mol % After synthesis, the concentrations of impurities in the silane and fractions isolated by its distillation purification lie in the range n x 10.sup.-6 - n x 10 mol % The limits of detection for impurities are 1 x 10.sup.-8-9 x 10.sup.-4 mol %

Author(s): A. Yu. Sozin [sup.1], O. Yu. Chernova [sup.1], T. G. Sorochkina [sup.1], A. P. Kotkov [sup.1] [sup.2], N. D. Grishnova [sup.1] [sup.2], D. M. Polezhaev [sup.2], G. V. Pushkarev [...], A method of chromatography-mass spectrometry is used to study the impurity composition of arsine synthesized by the reaction of arsenic chloride with sodium borohydride. Capillary adsorption columns with adsorbents modified silica and polytrimethylsilylpropine is used for the separation of impurities. Impurities are identified by comparing their mass spectra with the NIST database, published data, as well as by reconstructing their structures from fragment ions. Impurities of permanent gases; saturated and unsaturated hydrocarbons C.sub.1-C.sub.6; chlorinated, oxygenated, and aromatic hydrocarbons; volatile inorganic hydrides; and alkyl derivatives of arsine, trimethyl fluorosilane, carbon sulfur dioxide, and dimethyl sulfide are identified in arsine. Mass spectra of C.sub.2H.sub.3AsH.sub.2, CH.sub.3AsHC.sub.2H.sub.5, and C.sub.2H.sub.5As.sub.2H.sub.3 impurities are obtained for the first time.

A procedure was developed for the gas-chromatographic determination of hydrocarbons in silicon tetrafluoride of natural and isotopically enriched compositions. For improving the efficiency of the chromatographic determination of impurities, it was proposed that the major compound be removed from the test sample with the subsequent cryofocusing of impurity hydrocarbons. The detection limits of C1-C4 hydrocarbons were 2 × 10−6−6 × 10−6 vol %. [ABSTRACT FROM AUTHOR]