Claims
- 1. A porous gas filter for use as a vehicle compartment filter, or the like, said filter in the form of a unified molded body, said filter body comprising;
- adsorbent particles and particulate thermoplastic binder particles fused into agglomerate particles having a range of particle sizes of random and irregular shapes, and an average particle size of about 15 mesh or larger, said binder particles having an average particles size less than said adsorbent particles;
- said agglomerates fused into said molded filter body providing open interstices between said agglomerates.
- 2. The porous filter of claim 1 wherein said adsorbent particles have an average particle size of about 100 mesh or larger.
- 3. The porous filter of claim 2 wherein the binder particle average size is 20% or less than the adsorbent particle average size.
- 4. The porous filter of claim 3 wherein the adsorbent particles have an average particle size of 70 mesh or larger.
- 5. The porous filter of claim 4 wherein the molded body has two opposing faces, the pressure drop across a standard 8.89 mm thickness between said two faces being 49 Pascals or less at an air flow rate of 30 m.sup.3 /hr and a surface area of 77 cm.sup.2.
- 6. The porous filter of claim 1 wherein the adsorbent particles comprise carbon granules.
- 7. The porous filter of claim 6 wherein said initial toluene removal efficiency is at least 75% that of a comparable porous filter formed without agglomeration of the adsorbent particles at a pressure drop of less than about 98 Pascals for an 8.89 mm thick filter at an air flow rate of 30 m.sup.3 /hr and a surface area of 77 cm.sup.2.
- 8. The porous filter of claim 6 wherein said initial toluene removal efficiency is at least 90% that of a comparable porous filter formed without agglomeration of the adsorbent particles at a pressure drop of less than about 147 Pascals for an 8.9 mm thick filter at an air flow rate of 30 m.sup.3 /hr and a surface area of 77 cm.sup.2.
- 9. The porous filter of claim 1 wherein said molded filter body has at least one profiled face.
- 10. The porous filter of claim 9 wherein the molded filter body has two opposing profiled faces.
- 11. The porous filter of claim 10 wherein the profiled faces are each a series of alternative peaks and valleys in the form of a zig-zag where the peak of one face is directly opposite the valley of the opposing profiled face.
- 12. A porous filter apparatus for use as a vehicle compartment filter, or the like, said filter in the form of a molded body, said vehicle filter apparatus comprising:
- an air moving means in fluid communication with said molded filter body;
- a filter housing for said molded filter body, said molded filter comprising adsorbent particles and particulate thermoplastic binder particles fused into agglomerate particles having a range of particle sizes of random and irregular shapes, and an average particle size of about 15 mesh or larger, said binder particles having an average particles size less than said adsorbent particles;
- said agglomerates fused into said molded filter body providing open interstices between said agglomerates.
- 13. The porous filter apparatus of claim 12 wherein said adsorbent particles have an average particle size of about 100 mesh or larger.
- 14. The porous filter apparatus of claim 13 wherein the binder particle average size is 20% or less than the adsorbent particle average size.
- 15. The porous filter apparatus of claim 14 wherein the adsorbent particles have an average particle size of 70 mesh or larger.
- 16. The porous filter apparatus of claim 12 wherein the molded body has two opposing faces, the pressure drop across a standard 8.9 mm thickness between said two faces being 49.0 Pascals or less at an air flow rate of 30 m.sup.3 /hr and a surface area of 77 cm.sup.2.
- 17. The porous filter apparatus of claim 12 wherein the adsorbent particles comprise carbon granules.
- 18. The porous filter of claim 17 wherein said initial toluene removal efficiency is at least 75% that of a comparable porous filter formed without agglomeration of the adsorbent particles at a pressure drop of less than about 98 Pascals for an 8.9 mm thick filter at an air flow rate of 30 m.sup.3 /hr and a surface area of 77 cm.sup.2.
- 19. The porous filter apparatus of claim 17 wherein said initial toluene removal efficiency is at least 90% that of a comparable porous filter formed without agglomeration of the adsorbent particles at a pressure drop of less than about 147 Pascals for an 8.9 mm thick filter at an air flow rate of 30 m.sup.3 /hr and a surface area of 77 cm.sup.2.
- 20. The porous filter of claim 12 wherein the profiled faces are each a series of alternative peaks and valleys in the form of a zig-zag where the peak of one face is directly opposite the valley of the opposing profiled face.
- 21. The porous filter of claim 20 wherein the profiled faces are each a series of alternative peaks and valleys in the form of a zig-zag where the peak of one face is directly opposite the valley of the opposing profiled face.
- 22. The porous filter of claim 21 wherein the profiled faces are each a series of alternative peaks and valleys in the form of a zig-zag where the peak of one face is directly opposite the valley of the opposing profiled face.
- 23. A method for forming a porous filter comprising;
- heating adsorbent particles to a temperature above the softening point of a thermoplastic binder particle,
- mixing said heated adsorbent particles with said thermoplastic binder particles wherein said thermoplastic binder particles have an average size at least 20% less than the adsorbent particle average size,
- agglomerating said adsorbent particles and binder particles into agglomerates having an average size of about 15 mesh or larger,
- forming said agglomerates into a predetermined shape, and
- heating said agglomerates to a uniform temperature above the softening point of said thermoplastic binder to form a fused filter body.
- 24. The method of claim 23 wherein the adsorbent particles are heated to a temperature at least 5.degree. C. above the binder particle softening point.
- 25. The method of claim 24 wherein said adsorbent particles have an average particle size of about 100 mesh or larger and the adsorbent particles comprise carbon granules.
- 26. The method of claim 23 wherein the adsorbent particles are heated to a temperature at least 10.degree. C. above the binder particle softening point.
- 27. The method of claim 23 wherein the agglomerates are formed into said predetermined shape by placing them in a mold with substantially no compression.
- 28. The method of claim 27 wherein the mold is turned over at least once during the heating process to form the fused body.
- 29. The method of claim 27 wherein the agglomerates are shaped in two mold halves each having an open top and a profiled face wherein the two molds are joined to provide a fused unitary filter body having two profiled faces.
Parent Case Info
This application is a continuation-in-part of U.S. Ser. No. 07/921,234, filed Jul. 29, 1992, now abandoned.
US Referenced Citations (28)
Foreign Referenced Citations (8)
Number |
Date |
Country |
0399730 |
Nov 1990 |
EPX |
0491175 |
Jun 1992 |
EPX |
3817084 |
Sep 1989 |
DEX |
52-040868 |
Mar 1977 |
JPX |
52-040869 |
Mar 1977 |
JPX |
4-180808 |
Nov 1990 |
JPX |
1390668 |
Apr 1975 |
GBX |
2254257 |
Oct 1992 |
GBX |
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
921234 |
Jul 1992 |
|