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The examples examined relatively convincingly confirm the possibility of expanding the traditional areas of application of Graviton membrane based on poly-4-methylpentene and suggest membrane separation as a sufficiently competitive method of separation of gases and vapors.The hollow fibre membrane Graviton is manufactured by spinning from poly-4-methylpentene melt [I]. Apparatuses made from it are used to enrich air with oxygen, create an adjustable inert medium, and separate carbon dioxide from flue gases [2, 3]. The largest domestic installation for separation of air is the two-stage system using the Graviton 2 membrane. The installation can produce up to 210 m3/h of biowdown 95% N 2 dried to the dew point from 233 to 237 K and up to 130 m3/h of air with a 30 vol. % concentration of 0 2 fed to a station for aerobic biological purification of wastewaters [4].The following studies were conducted to expand the areas of application of apparatuses based on the Graviton membrane:-concentration of H 2 from blowdown gases in synthesis of NH 3 [5]; -separation of C2H 6 and C3H $, concentration of C3H 8 from mixtures with I-L,, CH 4, and C2H 6 [6], and separation of acid components (CO 2 in the presence of H2S) [7, 8] in processing of natural gas; -separation of CO from the ternary mixture CO2-O2:-CO [9] or H2--O 2 "fulminating mixture" [10, 11] in plasma chemical or radiolytic decomposition of H20; -separation and adjustment of the ratio of H 2 and CO in production of methanol, acetic acid, and other products of organic synthesis [ 12]; -use as an additional stage in extraction of He from the discharge stream of a short-cycle adsorption installation [ 13]. Both its insufftcient chemical resistance to the active components of the mixtures separated with prolonged use and the frequently low gas separation properties impede the industrial use of Graviton in many cases. As the analysis of the characteristics of the best domestic and foreign samples of membranes shows [ 14], Graviton is intermediate with respect to its gas separation properties. The insufficient permeability of the fibre is successfully compensated by its much higher packing density in the apparatus (up to 30,000 m3/m 2) in comparison to competing membranes of not only flat but also frequently of hollow-fibre geometry (in the Prism hollow-fibre apparatus from Monsanto, the packing density is 3,000 m3/m 2 [14]).Our method of gas-phase fluoride modification will increase the competitiveness and expand the range of gas separation problems that Graviton can solve by improving its selective and operating properties [15, 16]. By smoothly improving the selective properties and simultaneously increasing the chemical resistance of the membrane, the method allows creating unified technology for production of membrane apparatuses suitable for separation of very different gas mixtures, including in totally new areas of chemistry. The technological aspects of the creation and use of modified apparatuses based on Graviton membranes are examined in the present article.G...

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