Praxair Technology, Inc.

Philip Alexander Barrett

Neil Andrew Stephenson

Steven John Pontonio

Persefoni E Kechagia

Nicholas R Stuckert

Mark William Ackley

Jian Zheng

Hai Du

Henry Edward Howard

James R Handley

Garrett R Swindlehurst

Michael Freiert

Kerry C Weston

Raymond Francis Drnevich

Joseph Michael Schwartz

John Fredric Billingham

Richard M Kelly

Bernard Thomas Neu

Sadashiv M Swami

Rachael A Masin

Jesus Gallego-Preciado Nieto

Himanshu Saxena

Katie Held

Eustathios S Kikkinides

Christopher D Schotz

Katie Farley

Richard Martin Kelly

Michael T Freiert

Jesus Gallego-Praciado Nieto

The present invention relates to a surface modified zeolite adsorbent wherein the surface of said zeolite is modified with a coating comprised of a silicone derived species, said zeolite having a mean crystal size from about 5 to about 10 μm and a skeletal density of ≥1.10 gr./cc. The invention is based on the discovery that larger crystals tend to have higher particle density, and the packing of the larger crystals in agglomeration processes leads to more idealized packing to provide a larger mean-pore diameter. The surface modified adsorbent provides rate selectivity for one gas over others is described. The superior adsorbent has the added convenience of bead forming simultaneously with pore modification as well as having the treatment result in the yielding of high crush strength products.

Large crystal tunable adsorbents

The present invention relates to a superior carbon adsorbent with or without a core. In one embodiment the carbon adsorbent of the present invention employs carbon adsorbent powder and an organic binding agent which are combined together with an appropriate solvent in an agglomeration step. In another embodiment the invention contemplates a core-in-shell adsorbent comprising an outer shell composed of a carbon and a non-adsorbing inert inner core. Low temperature processing of these agglomerates substantially preserves the binding agent within the final composition and allows one to prepare adsorbent products of high sphericity. The adsorbents of the invention possess superior characteristics such as higher mass transfer rate and COworking capacity for use in a HPSA process.

Superior carbon adsorbents

The invention relates to a superior core-in-shell adsorbent comprising adsorbent, and an inert core, wherein said core possesses a porosity less than 10%, and has a volumetric thermal capacity greater than 1 J/K*cc. The adsorbents of the invention possess good physical strength, and allow a longer cycle time, thereby reducing the blowdown (vent) losses compared to known adsorbents. The invention relates to an adsorber design for a vacuum/pressure swing adsorption (VSA, VPSA, PSA) process designed to obtain oxygen product from air utilizing the adsorbents of the invention.

Superior core-in-shell component composite adsorbents for VSA/VPSA/PSA systems

The present invention relates to a method for modifying the crystalline inorganic framework of an adsorbent with coatings to provide rate selectivity for one gas over others is described. The method described herein narrows the effective pore size of crystalline porous solids with pores less than about 5 &#x212b; for rate selective separations. This method of the invention comprises treating the hydrated or partially hydrated zeolite with a silicone derived binding agent followed by subsequent heat treatment. The additive content and treatment are adjusted to match effective pore size to specific separations. The superior adsorbent has the added convenience of bead forming simultaneously with pore modification as well as having the treatment result in the yielding of high crush strength products.

Tunable adsorbents

The present invention generally relates to a pressure swing adsorption process for separating an adsorbate impurity from a feed stream comprising product gas, said process comprising feeding the feed stream to an adsorbent bed at a pressure of from about 60 psig to 2000 psig, wherein said adsorbent bed comprises adsorbent having: The invention also related to an adsorbent useful in PSA separations, particularly separating Nfrom methane, COfrom methane Ofrom Nand the like.

Characteristics of tunable adsorbents for rate selective separation of nitrogen from methane

The present invention relates to a method for modifying the crystalline inorganic framework of an adsorbent with coatings to provide rate selectivity for one gas over others is described. The method described herein narrows the effective pore size of crystalline porous solids with pores less than about 5A for rate selective separations. This method of the invention comprises treating the hydrated or partially hydrated zeolite with a silicone derived binding agent followed by subsequent heat treatment. The additive content and treatment are adjusted to match effective pore size to specific separations. The superior adsorbent has the added convenience of bead forming simultaneously with pore modification as well as having the treatment result in the yielding of high crush strength products.

The present invention relates generally to an attrition resistant core-in-shell composite adsorbent comprising at least a zeolite-containing COremoval adsorbent and a binder on an inert dense core. The attrition resistant core-in-shell composite adsorbent has an attrition loss of less than about 2 wt %. The core-in-shell composite adsorbent is preferably used in a multi-layered adsorption system in a cyclic adsorption process, preferably used in a PSA prepurification process prior to cryogenic air separation.

Core-in-shell composite adsorbent for use in PSA prepurifiers

An adsorption process for xenon recovery from a cryogenic liquid or gas stream is described wherein a bed of adsorbent is contacted with the aforementioned xenon containing liquid or gas stream and adsorbs the xenon selectively from this fluid stream. The adsorption bed is operated to at least near full breakthrough with xenon to enable a deep rejection of other stream components, prior to regeneration using the temperature swing method. Operating the adsorption bed to near full breakthrough with xenon, prior to regeneration, enables production of a high purity product from the adsorption bed and further enables oxygen to be used safely as a purge gas, even in cases where hydrocarbons are co-present in the feed stream.

Cryogenic adsorption process for xenon recovery

The invention relates to a process for removing oxygen from liquid argon using a TSA (temperature swing adsorption) cyclical process that includes cooling an adsorbent bed to sustain argon in a liquid phase; supplying the adsorbent bed with a liquid argon feed that is contaminated with oxygen and purifying the liquid argon thereby producing an argon product with less oxygen contaminant than is in the initial liquid argon feed; draining the purified residual liquid argon product and sending purified argon out of the adsorbent bed. Regeneration of specially prepared adsorbent allows the adsorbent bed to warm up to temperatures that preclude the use of requiring either vacuum or evacuation of adsorbent from the bed.

Purification of argon through liquid phase cryogenic adsorption

A method and apparatus for producing a purified liquid argon product in which liquid argon having oxygen impurities is produced in a cryogenic air separation plant by separating argon from oxygen within an argon column. An impure liquid argon stream, composed of part of the liquid argon, is purified in an adsorbent bed by adsorbing the oxygen impurities in an adsorbent to produce a purified liquid argon stream that constitutes the purified liquid argon product. During adsorption, the adsorbent bed is maintained at a reduced temperature with a coolant to prevent vaporization of the liquid argon. The bed is then regenerated by draining residual liquid argon from the adsorbent bed, introducing the residual liquid argon back into the air separation plant and then desorbing the oxygen impurities with a regeneration gas. After regeneration, the adsorbent bed is refilled with purified liquid argon prior to being brought back on-line.

Argon production method and apparatus

The present invention relates generally to compositions useful in adsorption and reactive processes comprising an adsorbent powder, such as a zeolite, and a binder mixed to form an agglomerate having a porosity of 0.30&#x2266;&#x3b5;&#x2266;0.42 and a Npore diffusivity D&#x2267;3.5&#xd7;10m/s and wherein the mean particle diameter of the crystalline zeolite powder is 10 &#x3bc;m or less; the mean particle diameter of the binder is 0.10 dor less, and the binder concentration is 10% or less expressed on a dry weight basis.

High rate compositions

Adsorbent compositions useful in adsorption and separation processes are made using silicone-derived binding agents. The adsorbent compositions are made from crystallite aluminosilicate particles bound with silicone-derived binding agents, and optionally small amounts of a clay binder, to form agglomerated crystallite particles and are calcined to volatilize the organic components associated with the silicone-derived binding agents. The agglomerated crystallite particles have superior pore structures and superior crush strengths at low binder concentrations and exhibit enhanced Nadsorption rates and capacities when used in air separation processes.

Adsorbent compositions

An optimal material composition that allows for the purification of at least one feed component from a fluid feed stream such that the adsorbent has an oxygen capacity of at least 10 weight percent is described. More specifically, the material is an adsorbent for purification of a fluid feed stream having an oxygen to argon selectivity greater than or equal to a ratio of 3:1 and an oxygen capacity of greater than or equal to 10 weight percent, wherein the oxygen capacity is measured at a pressure in the range of about 9-10 Torr and a temperature of 77 degrees Kelvin after 4 hours of equilibration time and wherein the oxygen to argon selectivity is obtained by dividing the oxygen capacity by the argon capacity of the adsorbent measured at a pressure in the range of about 697-700 Torr and a temperature of 87 degrees Kelvin after 8 hours of equilibration time. The adsorption capacities are measured on a pure component basis.

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Tonawanda, NY, United States of America

Philip Alexander Barrett