Abstract: Pressure swing adsorption with increased recovery of a highly adsorbable product gas component is carried out with a cycling in which, during the flushing phase, and at least over the latter portion thereof, the flushing gas has a concentration in the product gas component which is substantially equal to that of the product gas. To further increase the yield and the concentration of the product gas component in the product gas, the pressure in the absorber is reduced over a time period between the termination of the adsorption phase and the beginning of the desorption phase, with the effluent gas during this reduction in pressure being reused in the pressure swing adsorption cycle.

Abstract: A process of and apparatus for producing oxygen with a low fraction of argon from a gaseous medium like air, in which a gaseous medium is introduced into a first adsorption unit to produce an intermediate gas enriched with oxygen and depleted of argon. The intermediate gas is then supplied to a second adsorption unit in which the final product gas is prepared as well as a by-product which is returned into the process. Each of the adsorption units includes at least two adsorbers operating in a working cycle wherein the working cycle of the adsorbers of the second unit lasts about twice as long as the working cycle of the adsorbers of the first unit. For allowing an evacuation of each adsorber and thus a regeneration thereof, a common vacuum pump is connected to each unit in such a manner that the regeneration of the adsorbers of the second unit is temporarily interrupted when one of the adsorbers of the first unit is evacuated.

Abstract: A pressure-swing adsorption system is used to enrich the methane content of mine gas obtained from bores around mine shafts or galleries from the customary 25 to 45% by volume to a product gas quality of 50% by volume. Using a carbon molecular sieve adsorbent, the adsorption is carried out at 5 to 8 bar and is followed by a uniflow expansion to an intermediate pressure and a counterflow expansion to a flushing pressure of 1.1 to 2 bar. Counterflow flushing is carried out with waste gas and the product gas is a mixture of the gases obtained by counterflow expansion and flushing.

Abstract: Method for separating gas mixtures resulting from direct flow loading of adsorption reactors by means of a pressure change technique in a two stage adsorption reactor consisting of a prefilter and a separating filter, whereby strongly adsorbable impurities from the gas mixture are adsorbed in the prefilter and the remainder of the undesirable gas components are adsorbed in the separating reactor. Thereby, product gas flows off at the end of the separating reactor shortly before the passage therethrough of a non-desirable gas component. Thereafter, the prefilter and the separating reactor are disconnected and the prefilter is partially relieved by a gas counter flow and the separating reactor is partially relieved by direct gas flow. After reconnection of prefilter and separating reactor the unit is further released in the counter current, subsequently rinsed and is again brought to charge pressure in the direct or counter current.

Abstract: A method using pressure adsorption techniques for separating individual gas components from gas mixtures on adsorption agents in which a gas mixture is fed under increased pressure onto and in contact with an adsorption agent layer maintained in a separation reactor wherein undesirable gas components are adsorbed and thereafter the product gas is discharged so that a subsequent build up of pressure to adsorption pressure takes place in the layer by gas flow in reverse direction with respect to the adsorption direction followed by a subsequent adsorption stage wherein in accordance with the invention the pressure relief and rinsing action are caused to occur in two stages using reverse direction of slow with respect to the direction of adsorption; the relief gas obtained from the first reverse flow pressure relief stage is used as a rinsing gas for the first rinsing stage; the relief gas obtained from the second reverse flow pressure relief stage is discharged as a remainder gas and the product gas is used as

Abstract: An initial gaseous mixture of at least two components is passed through an adsorber which preferentially adsorbs one of the components. This initially loads the adsorber. Subsequently, another gaseous mixture, having a greater proportion of the preferentially adsorbed component than the initial gaseous mixture, is passed through the adsorber so as to additionally load the adsorber. Part of the gas in the adsorber is then removed. This initially unloads the adsorber and yields a first fraction containing both components, with the proportion of the preferentially adsorbed component being greater than that in the initial gaseous mixture. The remainder of the gas in the adsorber is removed next so as to completely unload the adsorber. This results in a second fraction including both components and wherein the proportion of the preferentially adsorbed component is greater than that in both the second gaseous mixture to be passed through the adsorber and the first fraction removed from the adsorber.

Abstract: An initial gaseous mixture of at least two components is passed through an adsorber which preferentially adsorbs one of the components. This initially loads the adsorber. Subsequently, another gaseous mixture, having a greater concentration of the preferentially adsorbed component than the initial gaseous mixture, is passed through the adsorber so as to additionally load the adsorber. Part of the gas in the adsorber is then removed. This initially unloads the adsorber and yields a first fraction containing both components with the concentration of the preferentially adsorbed component being greater than that in the initial gaseous mixture. Subsequently, part of the gas still remaining in the adsorber is removed so as to further unload the adsorber.

Abstract: Process for preparing carbon containing molecular sieves adapted for separating small molecular gases in particular oxygen from nitrogen which comprises treating coke having a content of volatile components of up to 5% at 600.degree.-900.degree.C with a hydrocarbon splitting off carbon whereby the split-off carbon is deposited in the carbon framework of the coke under narrowing of the existing pores.

Abstract: Porous coke is impregnated with an organic compound which remains in the pores thereby causing a reduction in the effective size of the same. This results in molecular sieve coke capable of separating different gases, particularly oxygen and nitrogen, and capable of adsorbing smaller gas molecules more rapidly than larger gas molecules. The organic compound has a boiling point of at least 200.degree.C as measured at atmospheric pressure and of no more than 450.degree.C as measured in vacuum.

Abstract: Process for preparing carbon-containing molecular sieves adapted for separating small molecular gases, in particular oxygen, from nitrogen, which comprises treating coke having a content of volatile components of up to 5% at 600.degree. - 900.degree.C with a hydrocabon which splits off carbon whereby the split-off carbon is deposited in the carbon framework of the coke thereby narrowing the existing pores.

Abstract: Process for preparing carbon-containing molecular sieves adapted for separating small molecular gases, in particular oxygen, from nitrogen, which comprises treating coke having a content of volatile components of up to 5% at 600.degree. - 900.degree. C with a hydrocarbon which splits off carbon whereby the split-off carbon is deposited in the carbon framework of the coke thereby narrowing the existing pores.