Abstract: An acoustic oxygen sensor is provided which can be used in the output lines leading from the sieve beds. This sensor can be used in communication with a microprocessor to control the production and evacuation cycles of the sieve beds, i.e., for example to determine the period for which a bed is supplied with compressed air and communicates with the reservoir as well as to determine the pressure of the compressed air and to determine the amount of time that the product gas is fed through the flow equalization path to supply an aliquot of purging gas to a used bed. In the feedback loop, the microprocessor utilizes the measured oxygen concentration and flow rate to optimize the settings necessary to achieve maximum oxygen concentration and flow rate efficiency. Since the microprocessor has the ability to make incremental changes and compare relative values, the optimum values can be determined empirically eliminating the need to perform complex theoretical calculations.

Abstract: A process for separating oxygen and nitrogen using an adsorption system comprising at least one main adsorption vessel containing an adsorbent selective for one component and at least one auxiliary adsorption vessel containing an adsorbent selective for the same component, the auxiliary vessel(s) being operated under conditions which result in the production of a product gas of lower purity than the product gas from the main adsorption vessel(s). The lower purity product gas from the auxiliary vessel is used to purge or pressurize the main adsorption vessel(s).

Abstract: An air prepurification process carried out in a battery of three adsorption vessels arranged in parallel. The process includes three steps: a first step in which non-steady state PSA is carried out in the first and second vessels operated in alternating adsorption and bed regeneration mode while the adsorbent in the third vessel undergoes thermal regeneration; a second step in which non-steady state PSA is carried out in the second and third vessels operated in alternating adsorption and bed regeneration modes while the adsorbent in the first vessel undergoes thermal regeneration; and a third step in which non-steady state PSA is carried out in the first and third vessels operated in alternating adsorption and bed regeneration modes while the adsorbent in the second vessel undergoes thermal regeneration.

Abstract: This process carries out a cycle on a monoadsorber (1) connected, on the one hand, to at least one container (2, 3) via a line (8, 10) fitted with a variable-opening valve (9, 11) and, on the other hand, to a reversible compression/pumping machine coupled to a speed variator (5). Application in particular to the production of oxygen at a variable flow rate from atmospheric air.

Abstract: This invention relates to a VPSA method for the production of a product that is enriched with a more preferred gas from a mixture of the more preferred gas and a less preferred gas and, preferably to a VPSA method for the production of an oxygen-enriched product from air, using an oxygen-preferential adsorbent under equilibrium conditions. In a preferred embodiment the process uses a desorption purge at a nearly constant pressure that is selected to produce a steady stream of oxygen having a purity from 30% to 60% at a pressure in the range of 60 kPa to 20 kPa.

Abstract: A process and apparatus for separating the components of a gas mixture in a pair of adsorption vessels using a single gas compressor/pump to move gas into and out of the adsorption vessels. The cycle is such that the gas compressor/pump is in continuous operation. The adsorption cycle is non-symmetrical in that the series of steps carried out in one of the adsorbers is not the same as the series of steps carried out in the other adsorber. The apparatus includes an intermediate gas storage container which is used to temporarily store gas removed from the nonadsorbed gas outlet end of the adsorption vessels so that it can be used to partially pressurize the adsorption vessels upon completion of the adsorbent regeneration step of the adsorption cycle.

Abstract: A process is set forth for the selective removal of water, CO.sub.2, ethane and C.sub.3 + hydrocarbons from gas streams, particularly a natural gas stream comprising primarily methane. The process comprises contacting the gas stream with an adsorbent material consisting exclusively of one or more compounds which are basic (i.e. compounds which, when contacted with a pH neutral aqueous solution, cause such solution to have a pH greater than 7.0) and which are mesoporous (i.e. compounds which have moderately small pores providing a surface area less than 500 m.sup.2 /g). The key to the present invention is the use of a single homogenous adsorbent without sacrificing performance. Typical mesoporous adsorbents which are useful in the present invention include zinc oxide, magnesium oxide and, in particular, activated alumina.

Abstract: Krypton present in a trace amount in a gaseous oxygen/nitrogen mixture is effectively enriched by an adsorption/desorption process of the pressure variation mode using a system including at least three fixed bed adsorption columns packed with hydrogenated mordenite. At the end of adsorption operation in one column, a desorbed gas from another column is fed to the one column under substantially the same pressure as the pressure during adsorption operation for fully washing the one column. Thereafter, the one column is subject to desorption operation.

Abstract: A natural gas feed stream containing significant quantities of nitrogen and/or carbon dioxide can be increased to a content of greater than 95 percent by volume of natural gas, and preferably greater than about 98 percent, by passing the natural gas feed stream sequentially through three adsorbent beds that are cycled through seven phases comprising: an adsorption phase to adsorb a first gas, a first depressurization phase to remove feed gas from the voids in the adsorbent bed, a recycle phase to remove a second gas from the adsorbent by the passage of a second depressurization gas therethrough and to produce a recycle gas, a second depressurization phase to reduce the adsorbent bed pressure to about ambient and to produce the second depressurization gas, an evacuation phase where the pressure in the adsorbent is further reduced and an enriched primary gas product stream recovered, a pressurization phase where the pressure in the adsorbent bed is increased using secondary product gas from a bed in an adsorpti

Abstract: Process for treating a gas mixture by pressure swing adsorption wherein for each adsorber (1), the duration (T.sub.R) of the countercurrent recompression step is much less than that (T.sub.D) of the cocurrent decompression step. The process is particularly useful in the production of oxygen from atmospheric air.

Abstract: In a process of recovering oxygen-enriched gas by pressure swing adsorption with use of adsorbers (A, B) each packed with an adsorbent which selectively adsorbs nitrogen from a gas mixture mainly containing nitrogen and oxygen, recovery of remaining oxygen-enrich gas is fully carried out by pressure equalization between both adsorbers (A, B), and a vacuum pump (8) is always connected to either adsorber (A or B) for continuous evacuation of nitrogen. For this purpose, the pressure equalization between both adsorbers (A, B) is conducted at least in two steps wherein one adsorber (A or B) is pressurized, whereas the other adsorber (B or A) is pressurized, so that recovery of oxygen-enriched gas is possible until there is substantially no pressure difference between both adsorbers (A, B).

Abstract: A PSA method incorporating the invention is applicable to the separation of a preferred gas from a mixture of the preferred gas and a less preferred gas. The PSA method uses an adsorbent bed including one or more layers of O.sub.2 equilibrium selective adsorbents, and comprises the steps of: pressurizing the adsorbent bed to a high pressure with a feed of air to enable the adsorbent bed to adsorb O.sub.2 ; extracting from the bed at bed pressure, a flow of N.sub.2 and storing at least some of the flow in a product tank; desorbing O.sub.2 from the adsorbent bed by feeding void gas in the bed enclosure to a storage tank and venting the adsorbent bed to a low pressure region; purging the adsorbent bed by feeding thereto the void gas from the storage tank; and repressurizing the adsorbent bed to an intermediate pressure with a flow of void gas from the storage tank.

Abstract: The flow rate of a nonadsorbed product gas stream from a multiple unit PSA plant can be reduced in response to a reduced product demand by isolating all units in the plant and inserting an idle step into the adsorption cycle immediately following bed equalization steps of the cycle. In a preferred embodiment, the duration of the idle step is inversely proportional to the percentage reduction in the product demand. To maintain the product gas purity at the desired level, minor adjustments of the idle step duration can be made following adjustment to the idle step in response to a change in product demand.

Abstract: The present process is directed to the efficient recovery of helium gas from gas streams which contain about 25 percent by volume or more helium. The process comprises two stages of pressure swing adsorption, each stage being comprised of a plurality of interconnected adsorbent beds. In the first stage of pressure swing adsorption which is comprised of about five phases, the helium content of the gas stream is increased to 95 percent by volume or more. A secondary product gas stream from the first stage of pressure swing adsorption is fed to the second stage of pressure swing adsorption. The second stage of pressure swing adsorption increases the helium content of this primarily non-helium product gas to more than about 50 percent by volume. This gas now with a helium content of more than about 50 percent by volume is fed along with the gas stream as the input gas to the first stage of pressure swing adsorption.

Abstract: A pressure swing adsorption process which includes switching a plurality of adsorption columns packed with an adsorbent successively to an adsorption step, a pressure equalization step, an evacuation step, a vacuum purge step, a pressure equalization step and a repressurization step to allow a more strongly adsorbable component gas contained in a gaseous mixture to be adsorbed on the adsorbent and to separate a less strongly adsorbable component gas. The process further includes compressing the thus separated less strongly adsorbable component gas by a product gas compressor to supply it as a product gas.

Abstract: Vacuum pressure swing adsorption (VPSA) processing is carried out employing a processing sequence of ten steps that serves to enhance the productive capacity thereof for air separation and other desirable applications.

Abstract: An apparatus is provided for recovering volatile liquid vapor from an air-volatile liquid vapor mixture. The apparatus includes first and second reaction vessels. Each of these reaction vessel includes a bed of adsorbent having an affinity for the volatile liquid vapor. The apparatus also includes a pump and an absorber for regenerating either bed of adsorbent. Further, the apparatus includes a polisher including a polisher bed of adsorbent having an affinity for the volatile liquid vapor. This polisher bed adsorbs volatile liquid vapor and substantially clean air is exhausted when initially regenerating one of the two beds of adsorbent in the first and second reaction vessels. Still further, the apparatus also includes a cooperating valve and conduit system for interconnecting the other components. Further, the invention relates to a related process for recovering volatile liquid vapor and a method of reducing backpressure in a volatile liquid vapor recovery system or unit.

Abstract: A pressure swing adsorption process for the recovery of oxygen from air improves upon a prior art process by depressurizing the adsorbent bed within an adsorbent vessel to an intermediate pressure by releasing void space gas from the product end of the vessel to a low purity oxygen tank while concurrently evacuating the adsorbent vessel from the feed end. This action enables an increased speed of depressurization and a reduction of the cycle time. Further, the adsorbent bed is repressurized to an intermediate pressure from the product outlet end with gas from the low purity oxygen tank, while concurrently pressurizing the adsorbent vessel from the input feed end. This action increases the load time fraction for a feed/vacuum blower. Further, oxygen is introduced to the product end of the adsorbent bed vessel from a high purity oxygen tank (which provides product to downstream applications) while concurrently, air is introduced to the feed end of the adsorbent bed within the vessel.

Abstract: An improved process for the oxygen enrichment of air by vacuum swing adsorption, pressure swing adsorption or a combination thereof, wherein the improvement comprises providing at least one packing at each of the air inlet to and air outlet from the adsorber, the packing at the air inlet side of the adsorber comprising Na-Ca zeolite X with an SiO.sub.2 /Al.sub.2 O.sub.3 ratio of 2.0 to 2.5 and with a CaO/Al.sub.2 O.sub.3 ratio of 0.4 to 0.75, the ratio being dependent upon the air inlet temperature, at an air inlet temperature of 20.degree. to 30.degree. C., the CaO/Al.sub.2 O.sub.3 ratio of the Na-Ca zeolite X at the inlet zone being 0.4 to 0.6, at an air inlet temperature of 30.degree. to 40.degree. C., the CaO/Al.sub.2 O.sub.3 ratio of the Ca zeolite X at the inlet zone being 0.55 to 0.65 and at an air inlet temperature of 40.degree. to 50.degree. C., the CaO/Al.sub.2 O.sub.3 ratio of the Na-Ca zeolite X at the inlet zone being 0.6 to 0.

Abstract: Large vacuum pressure swing adsorption-oxygen plants are employed with four adsorption vessels, two air compressors, two vacuum pumps and an oxygen surge tank, operated on a (two) two-bed processing system basis. One two-bed system is offset from the other by one half of one half processing cycle. Reduced power and capital cost savings are achieved.

Abstract: A vacuum swing adsorption process for separating a feed gas mixture into a more strongly adsorbable component and a less strongly adsorbable component in a process employing two vacuum pumps and three adsorbent beds containing an adsorbent selective for the more strongly adsorbable component using countercurrent depressurization and cocurrent ambient feed repressurization simultaneous with product end to product end pressure equalization and a common-shaft machinery arrangement which allows the expansion energy contained in the countercurrent depressurization and cocurrent ambient feed repressurization streams to be recovered and utilized to reduce overall process power consumption. Addition of three valves and an expander element will also allow expansion energy in the product purge and pressure equalization streams to be recovered. Oxygen product can be recovered from air at low cost using the process.

Abstract: The disclosed hybrid membrane and pressure swing adsorption process can recover helium from source streams of about 0.5 to 5 percent by volume helium and concentrate the helium to a concentration of greater than about 98 percent by volume. The process comprises a membrane separation followed by two stages of pressure swing adsorption which are used in series. The source gas will primarily contain hydrocarbons but will contain some nitrogen. The membrane unit will contain a semipermeable membrane which is permeably selective for helium and will to the extent feasible reject hydrocarbons. The permeate gas will be increased in helium content by 2 to 10 times. Part of the residue gas is used in the regeneration of the adsorbent beds in the first stage of pressure swing adsorption. Each stage of pressure swing adsorption will contain a plurality of adsorbent beds, and will be cycled through multiple phases.

Abstract: A process for separating components of a gas by adsorption in an enclosure (1) divided into equal tight separated compartments (27) each provided with an adsorbent material (7, 8) chosen in function of the gas to be treated and each provided for temporarily allowing the gas to be treated to be introduced and at least one chosen component of the components of this gas to be evacuated whilst the other component or components of this gas are adsorbed by the material (7, 8), which process consists in introducing the gas to be treated into one of the compartments (27) until a predetermined pressure is reached while in the next compartments (27), gas to be treated is introduced in at least one compartment (27) and the chosen component is allowed to escape, the pressure in the next compartment (27) is allowed to drop so as to obtain a partial desorption of the non chosen component or components of the gas, a purging fluid is injected in the last compartment to achieve the final desorption, and device for carrying ou

Abstract: Chabazite, offretite, erionite, levyne, mordenite, gmelinite, zeolite A, zeolite T, EMC-2, ZSM-3, ZSM-18, ZK-5, zeolite L, and beta zeolite whose exchangeable cations are composed of 95 to 50% lithium ions, 4 to 50% of one or more of aluminum, cerium, lanthanum and mixed lanthanides and 0 to 15% of other ions are prepared by ion-exchanging the base zeolite with water-soluble trivalent ion salts and with water soluble lithium salts. The zeolites preferentially adsorb nitrogen from gas mixtures.

Abstract: A system is provided for recovering volatile-liquid vapor from an air-volatile liquid vapor mixture. The system includes a reaction vessel having a bed of adsorbent for adsorbing volatile liquid vapor and producing relatively volatile liquid vapor-free air. The system further includes a liquid seal vacuum pump for regenerating the adsorbent, a first conduit for circulating the air-volatile liquid vapor mixture through the system and a second conduit for circulating seal liquid to the vacuum pump. A cyclonic separator separates the seal liquid from the air-volatile liquid vapor mixture produced during bed regeneration. A mechanism is also provided for removing the volatile liquid vapor from the air-volatile liquid vapor mixture separated from the seal liquid. A method of recovering volatile liquid vapor from an air-volatile liquid vapor mixture is also disclosed.

Abstract: In a "vacuum" type cycle, the depressurization of a first adsorber at the high pressure of the cycle is effected by placing it in communication with the outlet of a second adsorber at the low pressure of the cycle. This communication takes place simultaneously with countercurrent pumping in a first stage for the second adsorber and in a second stage for the first adsorber, the recompression to the high pressure of the cycle being effected by production gas. Used for the production of oxygen from air.

Abstract: A method for recovering argon and hydrogen simultaneously from a feed mixture comprising argon, hydrogen, methane, nitrogen, ammonia, and moisture by passing a two stage adsorption separation (PSA). The feed gas including 4-6% hydrogen is sent to the first stage PSA to obtain a product hydrogen during the first period of adsorption step, and to obtain an intermediate product of argon and hydrogen mixture during the next period of adsorption step. The adsorbed gases are evacuated and sent to fuel gas. The intermediate product argon and hydrogen mixture is sent to the second stage adsorption bed. The effluent of adsorption step is recovered as another product hydrogen. After the adsorption step, the second stage adsorber is undergone concurrent blowdown, pressure equalization, argon recovery, argon purge, desorption production of argon, pressure equalization, pressurization with product hydrogen. Through such cyclic operation of two-stage PSA, high purity argon and hydrogen are recovered simultaneously.

Abstract: The disclosed pressure swing adsorption processes can recover helium from source streams of less than about 10 percent by volume helium and concentrate the helium to a concentration of greater than about 98 percent by volume. Two stages of pressure swing adsorption are used in series. The source of the helium gas will be natural gas wells. The source gas will contain hydrocarbons but in most instances the primary gas other than helium will be nitrogen. Each stage of pressure swing adsorption will contain a plurality of adsorbent beds, and preferably about four. In each stage the adsorbent beds will be cycled through multiple phases. In the first stage the adsorbent beds will sequentially undergo the phases of adsorption, recycle, depressurization, evacuation, helium pressurization and recycle feed pressurization.

Abstract: A process for separating a feed gas mixture into a more strongly adsorbable component and a less strongly adsorbable component in a plurality of adsorbent beds containing an adsorbent selective for the more strongly adsorbable component using cocurrent depressurization to provide purge gas and pressurization by product end to product end pressure equalization between beds simultaneous with cocurrent ambient and elevated pressure feed pressurization, and countercurrent evacuation. Oxygen product can be recovered from air at high recovery and adsorbent productivity levels using the process.

Abstract: Process swing adsorption processes for gas separation are carried out using overlapping pressure swing adsorption, feed gas repressurization and desorption steps. The adsorptive capacity of the system employed is increased, unit power consumption is decreased, and the overall efficiency of the operation is enhanced.

Abstract: A natural gas feed stream containing significant quantities of nitrogen can be increased to a content of greater than 95 percent by volume of natural gas, and preferably greater than about 98 percent, by passing the natural gas feed stream sequentially through at least four adsorbent beds which are cycled through six phases comprising an adsorption phase to adsorb natural gas, a recycle phase to remove feed gas from the voids in the adsorbent bed and nitrogen from the adsorbent by the passage of a depressurization gas therethrough to produce a recycle gas, a depressurization phase to reduce the adsorbent bed pressure to about ambient and to produce the depressurization gas, an evacuation phase where the pressure in the adsorbent is further reduced and an enriched natural gas product stream recovered, a pressurization phase where the pressure in the adsorbent bed is increased using nitrogen gas from a bed in an adsorption phase, and further pressurizing the adsorbent bed in a recycle feed pressurization phase

Abstract: Carbon dioxide is removed from gas streams comprised predominantly of gases that are less polar than carbon dioxide by passing the gas stream through a bed of type X zeolite having a silicon to aluminum atomic ratio not greater than about 1.15, thereby adsorbing the carbon dioxide from the gas stream. The process is particularly advantageous when applied to the removal of low levels of carbon dioxide from gas streams at temperatures above 20.degree. C.

Abstract: The present invention is an apparatus and method for preferentially adsorbing carbon monoxide from a gas stream containing carbon monoxide in the presence of water and potentially ammonia while not adsorbing methane, hydrogen or carbon dioxide which may be present in the gas stream using an adsorbent of a supported cuprous compound situated downstream serially from a pretreatment adsorbent of 3A zeolite which protects the cuprous compound from water. An additional pretreatment layer of a basic metal compound to protect the acid-unstable 3A zeolite layer is also contemplated.

Abstract: The present invention is an apparatus and process for separating oxygen from air by adsorption of at least nitrogen on multiple layers of air separation adsorbent in an adsorption bed wherein the multiple layers are Na X-zeolite followed by at least another layer of adsorbent selected from the group consisting of Ca X-zeolite, Li X-zeolite, Ca A-zeolite followed by Ca X-zeolite, Ca A-zeolite followed by Li X-zeolite, Ca X-zeolite followed by Li X-zeolite, Li X-zeolite followed by Ca X-zeolite and Mg A-zeolite followed by Ca X-zeolite.

Abstract: A process for treating a gaseous mixture, particularly air, by pressure swing adsorption (PSA), of the type in which three adsorbers (1 to 3) are used in each of which is carried out, for a given nominal production, a cycle comprising the following successive stages, the cycle being offset from one adsorber to the other by a third of the nominal duration (T) of the cycle:(a) a substantially isobaric adsorption phase at a high pressure (PM) of the cycle, by circulation of the mixture through the adsorber in a so-called co-current direction;(b) a desorption phase comprising a stage (b2) of pumping to a low pressure (P.sub.m) of the cycle less than atmospheric pressure, via a vacuum pump (7) of constant speed and continuous operation whose output is in the vicinity of atmospheric pressure; and(c) a repressurization phase of the adsorber to the high pressure of the cycle. During a reduction of the production flow rate, the mean intake pressure of the vacuum pump is raised for the duration of the cycle.

Abstract: The components of a gas mixture are separated by pressure swing adsorption in a plurality of adsorption vessels. In the first step of the half-cycle adsorption takes place in a first bed while the second bed undergoes countercurrent desorption. At the end of the first step the first bed is vented countercurrently and the first and second beds undergo, as a first bed equalization step, outlet-to-outlet equalization or outlet to both inlet and outlet equalization. The vent step may precede or be concurrent with the first bed equalization step. In a second equalization step the beds simultaneously undergo inlet-to-inlet and outlet-to-outlet equalization. The second bed is then further pressurized with nonadsorbed product gas. The half cycle is then repeated but with the first bed being substituted for the second bed and vice versa.

Abstract: The present invention provides a method for economical recovery of ethylene from ethylene-containing vent gas from a plant for production of ethylene oxide, wherein ethylene is separated from saturated hydrocarbons such as methane, ethane and oxygen and then recovered efficiently. In this method, the vent gas is made to contact with molecular sieve carbon to selectively adsorb ethylene without substantial adsorption of the oxygen contained in the vent gas, the ethylene then being desorbed and recovered.

Abstract: A pressure swing adsorption process employs a simultaneous equalization and evacuation step followed by simultaneous feed and product gas repressurization steps, resulting in faster processing, and a reduction in power requirements, in the recovery of oxygen and argon from feed air.

Abstract: A process claimed for the removal of VOCs from fluid streams. The process comprises a vacuum swing adsorption zone containing at least 2 adsorption beds wherein the adsorbent beds are cocurrently purged with a diluent stream comprising an inert gas prior to a countercurrent evacuation step. In addition, the adsorbent beds may contain a first adsorption layer comprising an adsorbent selective for the adsorption of the inert gas, whereby the inert gas is retained within the VSA system to prevent the creation of an explosive mixture upon the condensation of the desorbed VOCs.

Abstract: A method of rectifying a multicomponent mixture by pressure swing adsorption to separate primary and secondary components of the mixture. Two groups of adsorbent beds are used in the method and adsorbent beds of the two groups are employed in a paired relationship and subjected to feed, co-current depressurization, evacuation, and countercurrent repressurization stages. In the feed stages, pairs of the adsorbent beds are pressurized with the mixture to adsorb the primary component in a first group of the adsorbent beds and in an entry section of a second group of the adsorbent beds. Also during the feed stage, the secondary component is adsorbed in the second group of adsorbent beds in remaining sections thereof. During co-current depressurization, any of the secondary component adsorbed in the first group of adsorbent beds and part of the primary component is driven to the second group of adsorbent beds.

Abstract: A process claimed for the removal of VOCs from fluid streams. The process comprises a vacuum swing adsorption zone containing at least 2 adsorption beds wherein the adsorbent beds are cocurrently purged with a diluent stream comprising an inert gas prior to a countercurrent evacuation step. In addition, the adsorbent beds may contain a first adsorption layer comprising an adsorbent selective for the adsorption of the inert gas, whereby the inert gas is retained within the VSA system to prevent the creation of an explosive mixture upon the recovery of the desorbed VOCs.

Abstract: A process is set forth for purifying and liquefying a feed gas mixture with respect to its less strongly adsorbed component of lower volatility which integrates temperature swing adsorption (TSA), pressure swing adsorption (PSA) and cryogenic distillation to optimize overall performance. The TSA portion of the process is used to remove the strongly adsorbed component from the feed; the PSA portion of the process is used to remove the moderately strongly adsorbed component from the feed; and the cryogenic distillation portion of the process is used to remove the less strongly adsorbed component of higher volatility from the feed while also providing for the liquefaction of the product. A key to the present invention is the use of the PSA and distillation waste streams in the regeneration of the TSA and PSA adsorbents. An important application of the present invention is the purification and liquefaction of a natural gas feed stream with respect to its methane/C.sub.2 hydrocarbon component.

Abstract: The present invention provides a process for the recovery of methyl chloride from a mixture thereof with isobutane. The process employs pressure swing adsorption with a size selective adsorbent having a pore opening of between about 3.7.times.3.7 Angstroms and about 4.9.times.5.7 Angstroms, such as zeolite A, clinoptilolite and mixtures thereof to selectively adsorb methyl chloride from vent streams comprising methyl chloride and isobutane and recovering a tail gas stream enriched in methyl chloride. The process may be used in applications such as treating the vent gas streams from the direct synthesis of methyl chlorosilanes. The process provides an economical route to recovering a valuable raw material in the process of making silicones and reduces the volume and methyl chloride content of the vent stream which is typically incinerated to avoid the release of halogenated hydrocarbons to the atmosphere.

Abstract: The disclosure describes a sorbing apparatus for removing one or more undesirable components from an influent gas. The sorbing apparatus comprises at least one chamber having first and second ports and defining a gas flow path between the first and second ports. A sorbent bed having a sorbing region and a guard region is disposed in the sorbing chamber in the gas flow path. The sorbing region includes a first sorbent material and the guard region includes a second sorbent material. A gas control arrangement is coupled to the sorbing chamber to cyclically (1) direct the influent gas through the first port, through the sorbing region and the guard region of the sorbent bed and out the second port wherein the undesirable components are sorbed from the influent gas and (2) direct a purge gas through the second port, through the guard region and the sorbing region of the sorbent bed and out the first port wherein the sorbing region is regenerated.

Abstract: A process for separating a feed gas mixture into a more strongly adsorbable component and a less strongly adsorbable component in a plurality of adsorbent beds containing an adsorbent selective for the more strongly adsorbable component using pressurization by product end to product end pressure equalization between beds simultaneous with cocurrent ambient and elevated pressure feed pressurization, coproduction of product and purge gas, and cocurrent depressurization for pressure equalization gas simultaneous with countercurrent evacuation. Oxygen product can be recovered from air at high recovery using the process.

Abstract: A process claimed for the removal of VOCs from fluid streams. The process comprises a vacuum swing adsorption zone containing at least 2 adsorption beds wherein the adsorbent beds are cocurrently purged with at diluent stream comprising an inert gas prior to a countercurrent evacuation step. In addition, the adsorbent beds may contain a first adsorption layer comprising an adsorbent selective for the adsorption of the inert gas, whereby the inert gas is retained within the VSA system to prevent the creation of an explosive mixture upon the condensation of the desorbed VOCs.

Abstract: A trans-atmospheric pressure swing adsorption process is carried out using product gas for purge and partial repressurization in the production of oxygen from air. No transfer of gas is made directly from one bed to another, as for pressure equalization purposes, but the power requirements are reduced under controlled pressure swing conditions.

Abstract: A process for separating a feed gas mixture into a more strongly adsorbable component and a less strongly adsorbable component in a plurality of adsorbent beds containing an adsorbent selective for the more strongly adsorbable component with two cocurrent depressurizations, first to provide product and then to provide a purge gas, and using a combination of less strongly adsorbable component and feed gas mixture to repressurize the adsorbent bed. Oxygen product can be recovered from air at high recovery using the process.

Abstract: Vacuum and other pressure swing adsorption vessels are monitored, and corrective adjustments are made in the pressure equalization and/or repressurization steps in response to imbalances in the temperature profiles of the vessels in order to tune the system. The PSA process is also desirably purge tuned to avoid over purging or under purging of each vessel.

Abstract: A two stage pressure swing adsorption process is set forth for producing high purity oxygen from a feed air stream wherein carbon dioxide, water and preferably nitrogen are removed in the first stage and wherein an oxygen selective adsorbent is used to adsorb oxygen in the second stage. The oxygen product is recovered upon depressurization of the second stage. The high purity of the oxygen product is achieved by rinsing the oxygen selective adsorbent with oxygen prior to the depressurization step. A key to the present invention is that the effluent streams from the second stage feed and rinse steps are used to regenerate the first stage adsorbent(s) in a specific regeneration scheme.