Article with zeolitic particles bonded with resin

Abstract

The invention relates to an adsorbent article. The adsorbent article contains zeolitic particles which include at least one zeolitic adsorbent. The zeolitic particles are immobilized with at least one resin. According to one embodiment, the resin is in the form of particles, which can be melted to form bridges at points of contact between the zeolitic particles, thus immobilizing the zeolitic particles. The average size of the zeolitic particles can be between 0.03 mm and 3 mm. The zeolitic particles contain at least one zeolite and the zeolite content of the article is at least 60 weight percent, based on the weight of the article. The invention also relates to a method for separating a fluid from another fluid or from impurities, by contacting the fluid with the adsorbent article.

Claims

1. An adsorbent article comprising zeolitic particles of at least one zeolitic adsorbent, wherein the zeolitic particles are in the form of zeolite(s) agglomerated with one or more inorganic binders, said zeolitic particles in the form of zeolite(s) agglomerated with one or more inorganic binders having a zeolite content and further being immobilized with at least one resin, wherein the average particle size of the at least one zeolitic adsorbent in the form of zeolite(s) agglomerated with one or more inorganic binders is between 0.03 mm and 3 mm, limits included, and wherein the zeolite content in the article is equal to or greater than 60 wt %, relative to the total weight of the said article.

2. The article according to claim 1, wherein the zeolitic particles in the article comprise at least one zeolitic adsorbent in the form of zeolite(s) agglomerated with one or more inorganic binder selected from the group consisting of natural clays, synthetic clays, silica, alumina, and mixtures thereof.

3. The article according to claim 1, wherein the zeolitic particles have forms and shapes, wherein the forms and shapes are selected from the group consisting of beads, pellets, extrudates, crushed beads, crushed pellets, flakes, cracks, rounded shapes, not rounded shapes, hollowed shapes, not hollowed shapes, cenospheres, and mixtures thereof.

4. The article according to claim 1, wherein at least one zeolitic particle in said article has a dimension equal to or greater than 0.1 mm.

5. The article according to claim 1, wherein said zeolite particles comprise at least one zeolite selected from the group consisting of A zeolites (framework type LTA), chabazite (framework type CHA), clinoptilolite (framework type HEU), EMT (framework type EMT), ZSM-5 (framework type MFI), Silicalite-1 (framework type MFI), and faujasite (framework type FAU), and mixtures thereof.

6. The article according to claim 5, wherein the FAU type zeolites are selected from the group consisting of zeolites X, zeolites MSX, zeolites LSX and zeolites Y, and mixtures thereof in all proportions.

7. The article according to claim 1, wherein the inorganic binder is selected from the group consisting of kaolins, kaolinites, nacrites, dickites, halloysites, attapulgites, sepiolites, delaminated clays, delaminated clays in the form of gels, montmorillonites, bentonites, illites, metakaolins, and mixtures thereof in any proportions.

8. The article according to claim 1, wherein the at least one resin is selected from the group consisting of polymers, thermoplastic homo-polymers, thermoplastic copolymers, polycondensates and mixtures thereof.

9. The article according to claim 1, wherein the at least one resin is selected from the group consisting of polymers, polyolefins, polypropylene, ethylene copolymers, copolymers of ethylene-vinyl acetate, polyacrylics, acrylonitrile homo-polymers, acrylonitrile co-polymers, polyacrylates, polymethacrylates, acrylate copolymers, methacrylate copolymers, polystyrenes, styrene copolymers, homo-polyesters, co-polyesters, halogenated polymers, halogenated copolymers, fluorinated homopolymers, fluorinated copolymers, homo-polyamides, co-polyamides, aromatic polyamides, polyvinylchlorides, polyurethanes, polyether sulfones, polyether ketones, polycarbonates, epoxy resins, phenolic resins, thermosetting resins, elastomeric resins, and mixtures thereof.

10. The article according to claim 1, wherein the weight of zeolite content relative to the total weight of the said article, is equal to or greater than 88 wt %.

11. The article according to claim 1 wherein the article has a shape selected from the group consisting of cubes, parallelepipeds, spheres, sheets, pleated sheets, films, pleated films, cylinders, convex regular polyhedrons, prisms, cones, ellipses, pyramids, wave shaped pattern, helical, and mixtures thereof.

12. The article according to claim 1, wherein the article comprises one or more features used to increase surface area, wherein the features are selected from the group consisting of protrusions, protruding cones, protruding cylinders, protruding concentric circles, protruding fins, protruding fins with supports, bores, tapered bores, non-tapered bores, partial bores, through bores, circular cross sectional shapes, polygonal cross sectional shapes, star cross sectional shapes, and combinations thereof.

13. The article according to claim 1, wherein the article comprises one or more channels, wherein the channels are circular, polyhedral, or sinusoidal.

14. The article according to claim 1, wherein the article has a mechanical resistance, expressed as compressive strength, between 290 psi (2 MPa) and 14500 psi (100 MPa), limits included.

15. A method for separating a fluid from one or more other fluid(s) or separating said fluid from impurities contained in said fluid, wherein the method comprises the step of contacting said fluid with at least one article according to claim 1.

16. The method according to claim 15, wherein the method comprises at least one of drying, conditioning, purifying, or separating, and the fluid is selected from the group consisting of gases, liquids, vapors, and mixtures thereof.

17. A blend comprising zeolitic particles having a zeolitic particle size, and resin particles having a resin particle size, wherein the resin particles are in the form of beads, agglomerates of beads, or aggregates of beads, and wherein the volumetric average resin particle size is less than 100 m.

18. The blend according to claim 17, wherein the blend has a particle size ratio defined as the ratio of [(resin particle size):(zeolitic particle size)] that is between 1:20000 and 3:1, limits included.

19. The article according to claim 1, wherein the inorganic binder comprises at least one member selected from the group consisting of natural clays, synthetic clays, silica, and alumina.

20. The article according to claim 1, wherein said at least one resin comprises at least one member selected from the group consisting of copolymers of ethylene-vinyl acetate, homo- and co-polyesters, halogenated polymers and copolymers, homo- and co-polyamides, and polyurethanes.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a cross section view of an example of an article (A) according to the present invention: the article comprises zeolitic particles (1), with at least one zeolitic adsorbent, the said particles which are immobilized with at least one resin (2).

(2) FIG. 1 bis is a SEM image of a cross-section of an article according to the present invention, as illustrated by FIG. 1. The article is prepared with 95 wt % of Siliporite Nitroxy SXSDM agglomerates (beads on the Figure) and 5 wt % of Dakota UNEX EVA T1 (grade 0-200 m) resin. Beads are bound together with resin bridges at points of contact. One of the advantages of the resin bridges is that a large portion of the surface of the beads remains free from resin, thereby allowing an optimized volumetric efficiency.

(3) Article (A) of FIG. 1 is illustrated in FIG. 2 which is a cross section view of an example of adsorbent cartridge (B). Cartridge (B) is an assembly of an article (A), which is inserted in a vessel (6) (made of polymer or metal such as aluminum), bearing a seal housing (7) between the article and the wall of the vessel, in order to prevent any channeling at the wall so that the fluid is forced through the article, and bearing caps (3, 3) tightly maintained by screws (4) and with seals (5) (O-rings represented). Flow at the inlet (10) is distributed through the flow distribution section (8) and filter (9). Purified or separated flow is produced at the outlet (11).

(4) FIG. 3 is a cross section view of another example of a cartridge (C) using the article (A). The article is directly stuck to the containing vessel (14) thanks to the resin (2), avoiding any channeling so that the fluid is forced through the article. Caps (13, 13) are sealed to the containing vessel (14) and to the flow distribution section (12). Flow at the inlet (10) is distributed through the flow distribution section (12). Purified or separated flow is produced at the outlet (11).

(5) FIG. 4 is a cross section view of an example of a cartridge (D) using the article (A). Cartridge (D) is an assembly of an article (A), which is inserted in a vessel (15) (made of polymer or metal such as aluminum), and caps (14) tightly maintained by screws (4). Flow at the inlet (10) is distributed from axial flow to radial flow. Purified or separated flow is produced at the outlet (11) from radial flow to axial flow.

(6) FIG. 5 is an SEM image of the dry formulation blend obtained at step a) of the process as described herein-before, i.e. prior to being immobilized with the compression molding process. The blend consists of 88 wt % of CECA's Siliporite Nitroxy SXSDM beads and 12 wt % of Arkema Kyblock FG-81 resin. The SEM image was performed by coating a thin layer of iridium using an ion beam coater from Southbay Technologies, model IBSe. SEM images were obtained with a Hitachi SU8010 field emission SEM. This image shows compatibility of fully dispersed coating of Kyblock FG-81 resin onto the surface of the Siliporite Nitroxy SXSDM beads.

(7) FIG. 6 is an SEM image of another example of a dry formulation blend obtained at step a) of the process as described herein-before, i.e. prior to being immobilized with the compression molding process, without inorganic resin. The blend consists of 88 wt % of CECA's Siliporite NK30 zeolite powder and 12 wt % of Arkema Kyblock FG-81 resin. The SEM image was performed by coating a thin layer of iridium using an ion beam coater from Southbay Technologies, model IBSe. SEM images were obtained with a Hitachi SU8010 field emission SEM. This image shows compatibility of fully dispersed coating of Kyblock FG-81 resin onto the surface of the Siliporite NK30 zeolite powder.

DETAILED DESCRIPTION OF THE INVENTION

(8) The invention is further illustrated with the following examples which do not aim at bringing any limitation to the sought scope of protection as shown in the annexed claims.

(9) Example 1 is a compression molded cylinder shape adsorbent article according to the invention consisting 80 wt % of CECA Siliporite Nitroxy SXSDM beads (Lithium exchanged LSX zeolite) and 20 wt % of Arkema Kyblock FG-81 resin. The article of Example 1 has high bulk density and excellent mechanical integrity. To manufacture this article the 20 wt % of Arkema Kyblock FG-81 resin is added to 80 wt % of CECA Siliporite Nitroxy SXSDM beads having an average particle size of 0.52 mm. Kyblock FG-81 is sold as agglomerates of 1-10 m volumetric average size, which agglomerates consist of resin particles of 150-300 nm average volumetric size.

(10) The two components were manually mixed into a homogeneous mixture using a low shear swiping technique in a mixing bowl with a synthetic mixing paddle for 15 minutes until the binary blend is a homogeneous mixture. While mixing, the forming die is preheated in an oven to 180 C. Once the forming die reaches a 180 C. equilibrium temperature then the mixture is added into the forming die of 5.42 cm diameter and compressed with 87 psi (0.6 MPa) of pressure for 1 minute. The article is then manually extracted and placed into the 180 C. preheated oven for 5 minutes to fully cure the article. The article is then removed and allowed to cool to room temperature, in a closed vessel to prevent moisture adsorption by the article.

(11) The final article has dimensions of 5.42 cm diameter and 3.95 cm height. The LSX zeolite content analysed by XRD is 66 wt % relative to the total weight of the article. The following characteristics of the article are determined according to the techniques described herein-below:

(12) Crushing strength value: 0.5 MPa.

(13) Attrition value: 0.6%.

(14) Volumetric efficiency: 0.130 g cm.sup.3.

(15) Example 2 is a compression molded cylinder shape adsorbent article consisting of 95 wt % of CECA Siliporite Nitroxy SXSDM beads and 5 wt % of Arkema Kyblock FG-81 resin. The article of Example 2 has high bulk density and excellent mechanical integrity. To manufacture this part the 5 wt % of Arkema Kyblock FG-81 resin is added to 95 wt % of CECA's Siliporite Nitroxy SXSDM beads. The LSX zeolite content analysed by XRD is 79 wt % relative to the total weight of the article.

(16) The two components are manually mixed into a homogeneous mixture using a low shear swiping technique in a mixing bowl with a synthetic mixing paddle for 15 minutes until the binary blend is homogeneous. While mixing the forming die is preheated in an oven to 180 C. Once the forming die reaches a 180 C. equilibrium temperature then the mixture is added into the forming die of 5.42 cm diameter and compressed with 87 psi (0.6 MPa) of pressure for 1 minute. The article is then manually extracted and placed into the 180 C. preheated oven for 5 minutes to fully cure the article. The article is then removed and allowed to cool to room temperature, in a closed vessel to prevent moisture adsorption by the article. The final article has dimensions of 5.42 cm diameter by 3.59 cm height. The following characteristics of the article are determined according to the techniques described herein-below:

(17) Crushing strength value: 0.3 MPa.

(18) Attrition value: 0.8%.

(19) Volumetric efficiency: 0.168 g cm.sup.3.

(20) Example 3 is prepared according to the Example 1 with 95 wt % of CECA Siliporite Nitroxy SXSDM beads and 5 wt % of Dakota UNEX EVA T1 resin (grade 0-200 m). The LSX zeolite content analysed by XRD is 79 wt % relative to the total weight of the article. The following characteristics of the article are determined according to the techniques described herein-below:

(21) Crushing strength value: 2.6 MPa.

(22) Attrition value: 1.3%.

(23) Volumetric efficiency: 0.164 g cm.sup.3.

(24) Example 4 is prepared according the Example 1 with 95 wt % of CECA Siliporite Nitroxy SXSDM beads and 5 wt % of Dakota UNEX EVA T1 resin (grade 0-80 m). The LSX zeolite content analysed by XRD is 79 wt % relative to the total weight of the article. The following characteristics of the article are determined according to the techniques described herein-below:

(25) Crushing strength value: 1.3 MPa.

(26) Attrition value: 0.7%.

(27) Volumetric efficiency: 0.172 g cm.sup.3.

(28) Example 5 is prepared according the Example 1 with 95 wt % of CECA Siliporite Nitroxy SXSDM beads and 5 wt % of Arkema Orgasol 2002 D NAT1 resin with a particles size 202 m. The LSX zeolite content analysed by XRD is 79 wt % relative to is the total weight of the article. The following characteristics of the article are determined according to the techniques described herein-below:

(29) Crushing strength value: 2.0 MPa.

(30) Attrition value: 0.5%.

(31) Volumetric efficiency: 0.163 g cm.sup.3.

(32) Example 6 is prepared according the Example 1 with 95 wt % of CECA Siliporite Nitroxy SXSDM beads and 5 wt % of Arkema Orgasol 2002 ES6 NAT3 resin with a particles size 603 m. The LSX zeolite content analysed by XRD is 79 wt % relative to the total weight of the article. The following characteristics of the article are determined according to the techniques described herein-below:

(33) Crushing strength value: 2.2 MPa.

(34) Attrition value: 0.7%.

(35) Volumetric efficiency: 0.160 g cm.sup.3.

(36) Example 7 is the use of articles of the present invention in a stationary medical Oxygen concentrator sold by Philips Respironics named EverFlo. Such medical oxygen concentrator uses a pressure swing adsorption (PSA) process to produce oxygen by extraction of the nitrogen from the ambient gas mixture, which generally is air. EverFlo concentrator uses two cylindrical cartridges filled with free zeolitic particles.

(37) In a comparative experiment, the free zeolitic particles present in the cylindrical cartridges are replaced with two articles according to the present invention, wherein the zeolitic particles are bonded with resin particles. In this comparative test, the two articles are directly molded into the two cartridges of the EverFlo concentrator (same volume filling and compacting with 0.6 MPa pressure). The articles consist of 95 wt % of CECA Siliporite Nitroxy SXSDM beads and 5 wt % of Arkema Kyblock FG-81 as prepared in Example 2.

(38) The concentrator is operated during 6 months (continuous operating with a produced flow rate set at a fixed value of 3 L min.sup.1). During the 6 months' period of continuous operating, the O.sub.2 purity measured on the produced flow rate in both experiments is similar, thereby showing that the presence of resin bonding the zeolitic particles has no impact on the purity of the produced oxygen.

(39) After the 6 months' period, the cartridges containing the articles of the present invention are opened and the presence of fines (dust) is visually assessed: it is observed that no dust is present in the cartridges and also no free beads is present in said cartridges.

(40) Characterization Techniques

(41) Morphology and Average Particle Size of Zeolitic Particles

(42) Forms and shapes of the zeolitic particles (morphology) are observed by Scanning Electron Microscopy (SEM). The average particle size of the zeolitic particles present in the article is the number average of the largest dimension of the zeolitic particles observed by SEM.

(43) Several photographs of polished cross-sections prepared by ion polishing are taken with a magnification at least equal to 50. The largest dimension of at least 200 zeolitic particles is measured thanks to a dedicated software, such as for example ImageJ (http://www.imagej.net). Precision is around 3%.

(44) Presence of Inorganic Binder in the Zeolitic Particles

(45) The adsorbent article is immersed in a solvent selected to dissolve the resin or heated under air to decompose the resin by combustion. Zeolite nature(s) and concentration(s) in the resulting particles are measured by XRD. Inorganic binder(s) correspond to the remaining part of the article after elimination of the resin and substraction of the crystal part (zeolitic part).

(46) In addition, polished cross-sections of the resulting particles are prepared by ion polishing. Analyses with Scanning Electron Microscopy coupled with energy dispersive X-ray spectrometry are carried out on the polished cross-sections to identify the different types of morphologies and the associated chemical compositions of each type of elements inside the particles (zeolite, binder). Inorganic binder(s) is the part of the particles which is not zeolitic.

(47) Zeolite Content

(48) The zeolite content, i.e. the total weight content of zeolitic part within the article, is determined by X-ray diffraction analysis, known to a person skilled in the art under the acronym XRD. This quantitative and qualitative analysis is carried out on a Bruker apparatus, by comparing the diffractograms of the article with the data from the ICDD databank and the amount of the zeolite or of each zeolite type is evaluated by means of the TOPAS software from Brucker. The zeolite weight content is equal to the sum of the contents of all the zeolites.

(49) Volumetric Efficiency

(50) Volumetric efficiency corresponds to the quantity of adsorbed water for cylinder-shaped sample of article having 5 cm in diameter and 3 cm height. The sample is placed during 24 hours in a closed vessel at 23 C.2 C., having relative humidity of 50%, and as described in patent application EP1223147A.

(51) Water adsorption values are measured by weighing the sample before and after this 24 hours' period. Volumetric efficiency is the weight increase of the sample divided by the volume of the cylinder (58.9 cm.sup.3).

(52) The sample may be a material according to the invention (article with zeolitic particles bonded with resin) or a sample of zeolitic particles without resin fulfilling a cylinder having same diameter and height, compacted under 1 MPa pressure.

(53) Volumetric efficiency ratio is the ratio of the volumetric efficiency of the article of the present invention to the volumetric efficiency of the above described sample of zeolitic particles without resin.

(54) Volumetric Average Particle Size of Resin (polymer) Particles

(55) The volumetric average particle size is measured using a 100 mL glass beaker, and adding 0.5 g of resin particles directly to 2 mL of 10% Triton X-100 solution in water. The resin powder and surfactant are mixed well, then the mixture is diluted by adding 60 mL of deionized water to the beaker. The beaker is placed in a sonicator to break down the agglomerates while continuously agitating the solution to prevent powder settling. The solution is used to measure the particle size distribution in the Microtrac S3500 analyzer.

(56) Mechanical Properties: Compressive Strength, Crushing Strength and Attrition Resistance

(57) Compressive strength: To determine the compressive strength of the article of the invention, a tensile/pressure tester from Zwick, model UP 1455 is employed. For this, cylindrical articles with a specimen diameter of 5 mm are cut to a specimen length of 7 mm. For exact and reproducible compressive strength measurements, it must be ensured that the front faces of the article are planar-parallel. The measurement is carried out at room temperature. The preliminary force is 1 N. The experiments are carried out at a test speed of 1 mm/min. The test force acts on the front faces.

(58) Crushing Strength: To determine the crushing strength of the article of the invention, another tensile/pressure tester from Instron, model 4505, cell 10 kN S/N UK1280, is also employed for cylindrical articles with a specimen diameter of 60 mm and a specimen length of 10 mm. For exact and reproductible crushing strength measurements, it must be ensured that the front faces of the article are planar-parallel.

(59) The measurement is carried out at room temperature. The experiments are carried out at a test speed of 1 mm/min, at room temperature (23 C.). The test force acts on the front faces through 150 mm plates.

(60) Attrition resistance: a wet attrition test is performed in the following conditions: 136 mL of cylindrical articles with specimen diameter of 5 mm and a specimen length of 7.5 mm, are placed in a cylindrical 150 mL container having a diameter of 4.4 cm and a height of 10 cm. 68 mL of ethanol are added, the container is closed and subjected to high frequency swirling motion in a Model No. 30 Red Devil Paint Conditioner for 30 minutes. The fines produced by attrition are measured: the fines are thereafter washed from the article samples with ethanol through a 1.25 mm standard sieve into a beaker and isolated from the ethanol, heated to 80 C. to dry the fines and weighed. The obtained weight is expressed as a weight percent of the initial charge.