Patent Application
20080011163
Features and advantages of the present disclosure will become apparent by reference to the following detailed description and drawings, in which like reference numerals correspond to similar, though not necessarily identical components. For the sake of brevity, reference numerals or features having a previously described function may not necessarily be described in connection with other drawings in which they appear.
Embodiments of the composite disclosed herein generally include a porous polymeric material having a sorbent/zeolite material incorporated therein. It is believed that the addition of the zeolite material to the porous polymeric material substantially reduces or eliminates handling powdered forms of zeolite when manufacturing a device in which it is used. Furthermore, the retainers and/or housings (e.g., having apertures suitable for containing the zeolite and allowing air flow) associated with the granular zeolite may also be substantially reduced or eliminated from the device. As the embodiments of the composite incorporate the zeolites directly therein (rather than containing them in a porous or screened housing), it is believed that zeolites having smaller, or variable, particle sizes may be used. Still further, the composite material may be formed to a desirable size, shape, and/or configuration and/or may be cut to a desirable length for various applications.
The composite disclosed herein may advantageously be used in any desirable gas separation device and/or process. A non-limitative example of such a device is an oxygen concentrator, and a non-limitative example of such a process is a natural gas treatment. It is believed that zeolites having a smaller particle size may advantageously decrease cycle times and output of pressure swing absorption (PSA) systems. The size of the zeolites may also offer a small, compact design for molecular sieve applications.
Although, as mentioned herein, zeolite particles are contemplated as being useful in various embodiment(s) of the present disclosure, it is to be understood that various sorbents suitable for use in embodiment(s) described herein may be used. Zeolites are one non-limitative example of sorbents.
Referring now to
It is to be understood that the porous polymeric material 12 may be purchased, or may be formed from the polymerization of monomers.
The integration of the plurality of zeolite particles 14 may be accomplished by any suitable technique, depending, at least in part, upon the specific composition of the porous polymeric material 12 and/or the zeolite particles 14. In an embodiment, integrating the plurality of zeolite particles 14 is accomplished by molding, impregnating, sintering (e.g., those sintering processes used with high temperature materials, metals (e.g., brass or bronze), etc.), extrusion processes, spray processes, foam formation processes, bubble formation processes, and/or combinations thereof.
It is to be understood that forming the porous polymeric material 12 and integrating the zeolite particles 14 therein may occur substantially simultaneously or sequentially.
The porous polymeric material 12 may be a non-hydroscopic material, or one that is substantially incapable of absorbing water. Non-limitative examples of such porous polymeric materials 12 include polypropylene, polyethylene, polystyrene, polyisobutylene, copolymers of styrene-butadiene, polybutadiene, some hydrophobic polyurethanes, and/or combinations thereof. In a non-limitative example, polypropylene beads and/or polyethylene beads may be bonded together to form porous filters of various shapes.
Generally, the sorbent particles 14 may be incorporated for gas separation and/or purification of an oxygen containing gas stream. In an embodiment, the sorbent particles 14 are capable of adsorbing nitrogen gas and/or some other gas(es) from a gas stream. Non-limitative examples of suitable sorbents for gas separation include zeolites commercially available from Tricat Zeolites GmbH, located in Bitterfeld, Germany; zeolites commercially available from UOP, located in Des Plaines, Ill.; Li-LSX beads; zeolite X; zeolite Y; zeolite LSX; MCM-41 zeolites; activated carbon; activated alumina; and/or silicoaluminophosphates (SAPOS); and/or combinations thereof.
In an embodiment of the composite material 10, each of the plurality of zeolite particles 14 may have a size ranging from about 100 microns to about 2,000 microns. It is to be understood that the size of the zeolite particles 14 may be adapted for a specific application. More specifically, the particle 14 size may be adapted for exposure to a predetermined gas flow or for forming the composite 10 so that it has a predetermined filtration ratio.
In an embodiment, the composite material 10 includes about 40% of the porous polymeric material 12 and about 60% of the zeolite particles 14. In another embodiment, the composite 10 includes the porous polymeric material 12 in an amount ranging from about 5% to about 70%, and the plurality of zeolite particles 14 in an amount ranging from about 30% to about 95%. In still another embodiment, the composite 10 includes the porous polymeric material 12 in an amount ranging from about 5% to about 40%, and the plurality of zeolite particles 14 in an amount ranging from about 60% to about 95%. It is to be understood that the ratio of polymeric material 12 to zeolite particles 14 may be adapted to provide the composite 10 with predetermined properties, such as, for example strength and/or adsorptivity. It is to be further understood that any suitable ratio of polymeric material 12 to zeolite particles 14 may be utilized, and the ratio may be adapted for a specific application, or to realize predetermined stress and/or strain ratings.
Referring now to
Embodiments of the composite material 10 disclosed herein include, but are not limited to the following advantages. The composite material 10 may advantageously be used in any desirable gas separation device and/or process. As the composite material 10 includes the sorbent particles 14 in the porous polymeric material 12, it is believed that smaller particle sizes may be used, if desired. Without being bound to any theory, it is believed that these smaller sized sorbent particles 14 may offer a small, compact design for molecular sieve applications. Furthermore, the size of the sorbent particles 14 advantageously decreases cycle times and output of pressure swing absorption (PSA) systems.
Still further, the addition of the sorbent particles 14 to the porous polymeric material 12 may substantially reduce or eliminate handling powdered forms of sorbent when manufacturing a device in which it is used. Still further, the composite material 10 may be formed to a desirable size, shape, and/or configuration and/or may be cut to a desirable length for a variety of applications (non-limitative examples of which include oxygen concentration, natural gas treatment, or the like).
While several embodiments have been described in detail, it will be apparent to those skilled in the art that the disclosed embodiments may be modified. Therefore, the foregoing description is to be considered exemplary rather than limiting.
