Abstract: The concentration of adsorbate in the feed gas to an on-stream bed of a cyclical swing adsorption process is monitored and the data processed to predict the time required to complete the on-stream mode of that bed and the purge flow rate and/or other regeneration mode operating condition of the concurrently off-stream bed is modified in response to changes in said predicted time whereby the regeneration mode of the off-steam bed is completed at the same time as the on-stream mode of the concurrent on-stream bed.

Abstract: Base treated aluminas exhibit improved CO2 capacity over untreated aluminas. Base treated aluminas prepared by physically mixing alumina and base during forming have (1) a higher surface area, (2) less hydrothermal aging, (3) improved CO2 capacity and (4) lower cost than base treated aluminas produced by aqueous impregnation. A method for removing at least CO2 and water from a gas stream includes providing an adsorbent formed from a process comprising physically mixing activated alumina solids and solid salts of alkali metals, alkaline earth metals or ammonium ion; and contacting the gas stream with the adsorbent.

Abstract: PSA process for oxygen production comprising (a) providing an adsorber having a first layer of adsorbent selective for water and a second layer of adsorbent selective for nitrogen, wherein the heat of adsorption of water on the adsorbent in the first layer is ?about 14 kcal/mole at water loadings ?about 0.05 to about 3 mmol per gram; (b) passing a feed gas comprising at least oxygen, nitrogen, and water successively through the first and second layers, adsorbing water in the first layer of adsorbent, and adsorbing nitrogen in the second layer of adsorbent, wherein the mass transfer coefficient of water in the first layer is in the range of about 125 to about 400 sec?1 and the superficial contact time of the feed gas in the first layer is between about 0.08 and about 0.50 sec; and (c) withdrawing a product enriched in oxygen from the adsorber.

Abstract: A process for selectively separating hydrogen from at least one more strongly adsorbable component in a plurality of adsorption beds to produce a hydrogen-rich product gas from a low hydrogen concentration feed with a high recovery rate. Each of the plurality of adsorption beds subjected to a repetitive cycle. The process comprises an adsorption step for producing the hydrogen-rich product from a feed gas mixture comprising 5% to 50% hydrogen, at least two pressure equalization by void space gas withdrawal steps, a provide purge step resulting in a first pressure decrease, a blowdown step resulting in a second pressure decrease, a purge step, at least two pressure equalization by void space gas introduction steps, and a repressurization step. The second pressure decrease is at least 2 times greater than the first pressure decrease.

Abstract: Hydrogen sulfide is removed from a hydrogen rich gas stream using adsorbents having a low loss of carbon dioxide adsorption capacity upon sulfur loading including high purity silica gels, titania or highly cross-linked, non-chemically reactive resins. The adsorbents may be used to adsorb both carbon dioxide and hydrogen sulfide, or may be used as a guard bed upstream of a separate carbon dioxide adsorbent.

Abstract: The concentration of adsorbate in the feed gas to an on-stream bed of a cyclical swing adsorption process is monitored and the data processed to predict the time required to complete the on-stream mode of that bed and the purge flow rate and/or other regeneration mode operating condition of the concurrently off-stream bed is modified in response to changes in said predicted time whereby the regeneration mode of the off-steam bed is completed at the same time as the on-stream mode of the concurrent on-stream bed.

Abstract: PSA process for oxygen production comprising (a) providing an adsorber having a first layer of adsorbent selective for water and a second layer of adsorbent selective for nitrogen, wherein the heat of adsorption of water on the adsorbent in the first layer is equal to or less than about 14 kcal/mole at water loadings less than about 0.05 mmol per gram; (b) passing a feed gas comprising at least oxygen, nitrogen, and water successively through the first and second layers, adsorbing water in the first layer of adsorbent, and adsorbing nitrogen in the second layer of adsorbent, wherein the mass transfer coefficient of water in the first layer is in the range of about 125 to about 400 sec?1 and the superficial contact time of the feed gas in the first layer is between about 0.08 and about 0.50 sec; and (c) withdrawing a product enriched in oxygen from the adsorber.

Abstract: The invention provides vacuum swing adsorption processes that produce an essentially carbon monoxide-free hydrogen or helium gas stream from, respectively, a high-purity (e.g., pipeline grade) hydrogen or helium gas stream using one or two adsorber beds. By using physical adsorbents with high heats of nitrogen adsorption, intermediate heats of carbon monoxide adsorption, and low heats of hydrogen and helium adsorption, and by using vacuum purging and high feed stream pressures (e.g., pressures of as high as around 1,000 bar), pipeline grade hydrogen or helium can purified to produce essentially carbon monoxide -free hydrogen and helium, or carbon monoxide, nitrogen, and methane-free hydrogen and helium.

Abstract: A process for selectively separating hydrogen from at least one more strongly adsorbable component in a plurality of adsorption beds to produce a hydrogen-rich product gas from a low hydrogen concentration feed with a high recovery rate. Each of the plurality of adsorption beds subjected to a repetitive cycle. The process comprises an adsorption step for producing the hydrogen-rich product from a feed gas mixture comprising 5% to 50% hydrogen, at least two pressure equalization by void space gas withdrawal steps, a provide purge step resulting in a first pressure decrease, a blowdown step resulting in a second pressure decrease, a purge step, at least two pressure equalization by void space gas introduction steps, and a repressurization step. The second pressure decrease is at least 2 times greater than the first pressure decrease.

Abstract: Method for the separation of a gas mixture comprising providing a PSA system with at least one adsorber vessel containing adsorbent material that is selective for the adsorption of carbon monoxide and nitrogen, passing a feed gas mixture containing at least hydrogen and carbon monoxide and optionally containing nitrogen through the adsorbent material in a feed step and withdrawing a purified hydrogen product from the adsorber vessel, wherein the feed step has a duration or feed time period of about 30 seconds or less. The adsorbent material is characterized by any of (1) a Henry's law constant for carbon monoxide between about 2.5 and about 5.5 (mmole/g)/atm; (2) a carbon monoxide heat of adsorption between about 6.0 and about 7.5 kcal/gmole; (3) a Henry's law constant for nitrogen greater than about 1.5 (mmole/g)/atm; and (4) a selectivity of carbon monoxide to nitrogen between about 5.0 and about 8.0.

Abstract: Method for the separation of a gas mixture comprising providing a pressure swing adsorption system having a plurality of adsorber vessels, wherein each vessel has an inlet, an outlet, and a bed of particulate adsorbent material disposed therein. The adsorbent material is selective for the adsorption of one or more components from the gas mixture, and each bed of adsorbent material is characterized by a bed depth and by an average particle diameter less than about 1.3 mm. A feed step is carried out during a feed time period wherein the gas mixture is introduced into the adsorber vessel, one or more components are selectively adsorbed from the gas mixture, and a product gas is withdrawn from the adsorber vessel. The bed depth in feet times the dimensionless ratio of the empty bed residence time to the feed time period is less than about 4.

Abstract: A process and an apparatus for removal of radon from indoor air. The process having the step of contacting indoor air with an adsorbent, that is a silver-exchanged zeolite. The apparatus for the removal of radon from indoor air comprises a silver exchanged zeolite.

Abstract: Pressure swing adsorption process for producing oxygen comprising (a) providing at least one adsorber vessel having a first layer of adsorbent adjacent the feed end of the vessel and a second layer of adsorbent adjacent the first layer, wherein the surface area to volume ratio of the first layer is in the range of about 5 to about 11 cm?1; (b) introducing a pressurized feed gas comprising at least oxygen, nitrogen, and water into the feed end, adsorbing at least a portion of the water in the adsorbent in the first layer, and adsorbing at least a portion of the nitrogen in the adsorbent in the second layer, wherein the superficial contact time of the pressurized feed gas in the first layer is between about 0.08 and about 0.50 sec; and (c) withdrawing a product gas enriched in oxygen from the product end of the adsorber vessel.

Abstract: PSA process for oxygen production comprising (a) providing an adsorber having a first layer of adsorbent selective for water and a second layer of adsorbent selective for nitrogen, wherein the heat of adsorption of water on the adsorbent in the first layer is ? about 14 kcal/mole at water loadings? about 0.05 mmol per gram; (b) passing a feed gas comprising at least oxygen, nitrogen, and water successively through the first and second layers, adsorbing water in the first layer of adsorbent, and adsorbing nitrogen in the second layer of adsorbent, wherein the mass transfer coefficient of water in the first layer is in the range of about 125 to about 400 sec?1 and the superficial contact time of the feed gas in the first layer is between about 0.08 and about 0.50 sec; and (c) withdrawing a product enriched in oxygen from the adsorber.

Abstract: A first aspect of a process of recovering xenon from feed gas includes: providing an adsorption vessel containing adsorbent having a Xe/N2 selectivity ratio <75; feeding into the adsorption vessel feed gas having an initial nitrogen concentration >50% and an initial xenon concentration ?0.5%; evacuating the adsorption vessel; and purging the adsorption vessel at a purge-to-feed ratio ?10. The final xenon concentration is ?15× the initial xenon concentration. A second aspect of the process includes providing an adsorption vessel containing adsorbent having a Xe Henry's law Constant ?50 mmole/g/atm; feeding into the adsorption vessel feed gas having an initial nitrogen concentration >50% and an initial xenon concentration ?0.5%; heating and purging the adsorption vessel to recover xenon having a final concentration ?15× its initial concentration. Apparatus for performing the process are also described.

Abstract: Purification material for removing a contaminant from an impure hydride gas comprising an adsorbent comprising a reduced metal oxide on a porous support and a desiccant. The porous support may be selected from the group consisting of activated carbon, alumina, silica, zeolite, silica alumina, titania, zirconia, and combinations thereof. The reduced metal oxide may comprise one or more metals selected from the group consisting of Group I alkali metals (lithium, sodium, potassium, rubidium, and cesium), Group II alkaline earth metals (magnesium, calcium, strontium, and barium), and transition metals (manganese, nickel, zinc, iron, molybdenum, tungsten, titanium, vanadium, cobalt, and rhodium). The desiccant may be selected from the group consisting of hygroscopic metal salts, zeolites, single metal oxides, mixed metal oxides, and combinations thereof.

Abstract: An improved thermal swing adsorption process is set forth which addresses the problem of water ingress into the adsorbent by periodically heating the adsorbent to a temperature greater than the temperature used in the normal regeneration cycle.

Abstract: Purification material for removing a contaminant from an impure hydride gas comprising an adsorbent comprising a reduced metal oxide on a porous support and a desiccant. The porous support may be selected from the group consisting of activated carbon, alumina, silica, zeolite, silica alumina, titania, zirconia, and combinations thereof. The reduced metal oxide may comprise one or more metals selected from the group consisting of Group I alkali metals (lithium, sodium, potassium, rubidium, and cesium), Group II alkaline earth metals (magnesium, calcium, strontium, and barium), and transition metals (manganese, nickel, zinc, iron, molybdenum, tungsten, titanium, vanadium, cobalt, and rhodium). The desiccant may be selected from the group consisting of hygroscopic metal salts, zeolites, single metal oxides, mixed metal oxides, and combinations thereof.

Abstract: A gas adsorption composite a high density adsorbent including a high density layer having a first density of at least 0.3 g/cc; and a low density adsorbent having a low density layer having a second density of less than 0.3 g/cc, wherein the high density adsorbent is in substantially contiguous contact with the low density adsorbent and each of the high density adsorbent and the low density adsorbent has an adsorbent surface area of at least 500 m2/g. A pressure swing adsorption process for recovering a product gas from a feed gas, the process including supplying a pressure swing adsorption apparatus including a gas adsorption composite, feeding a feed gas into the pressure swing adsorption apparatus during a feed period not exceeding 100 seconds and recovering the product gas from the pressure swing adsorption apparatus.

Abstract: The present invention describes a pressure swing adsorption (PSA) apparatus and process for the production of purified hydrogen from a feed gas stream containing heavy hydrocarbons (i.e., hydrocarbons having at least six carbons). The apparatus comprises at least one bed containing at least three layers. The layered adsorption zone contains a feed end with a low surface area adsorbent (20 to 400 m2/g) which comprises 2 to 20% of the total bed length followed by a layer of an intermediate surface area adsorbent (425 to 800 m2/g) which comprises 25 to 40% of the total bed length and a final layer of high surface area adsorbent (825 to 2000 m2/g) which comprises 40 to 78% of the total bed length.