Catalytic element with inductive heater
Catalytic elements are usable in waste gas control processes. The catalytic elements include an open inlet into a hollow body and a closed end thereby forcing fluid or gas through a porous catalytic layer of the element. The catalytic layer includes inorganic fibers and a catalyst disposed on or incorporated into the fibers. The catalytic element also includes an inductive heater disposed therein and a conductive layer about the inductive heater to transfer heat to the catalyst and fluid or gas.
1. A device comprising:
a housing;
an inductive heater disposed within the housing;
a conductive layer disposed within the housing radially outside of the inductive heater, wherein the conductive layer is gas permeable and thermally conductive; and
a catalytic layer disposed within the housing around the conductive layer, wherein the catalytic layer comprises inorganic fibers and a catalyst;
wherein the conductive layer is configured to transfer heat from the inductive heater to the catalytic layer.
2. The device of claim 1 , further comprising an end cap sealing one end of the conductive layer.
3. The device of claim 2 , wherein the end cap is not gas permeable.
4. The device of claim 3 , wherein the end cap is conical.
5. The device of claim 2 , wherein the end cap comprises a permeable catalytic layer.
6. The device of claim 1 , wherein the inorganic fibers comprise alumina fibers, alumino-silicate fibers, alumina-boria-silicate fibers, alumina-zirconia-silicate fibers, zirconia-silicate fibers, zirconia fibers, or combinations thereof.
7. The device of claim 1 , wherein the catalyst comprises platinum, rubidium, antimony, copper, silver, palladium, ruthenium, bismuth, zinc, nickel, cobalt, chromium, cerium, titanium, iron, vanadium, gold, manganese, or combinations thereof.
8. The device of claim 1 , further comprising a support layer secured radially outside and about the catalytic layer.
9. The device of claim 8 , wherein the support layer or the conductive layer comprises a catalyst.
10. The device of claim 1 , further comprising a non-conductive isolator covering at least a portion of the inductive heater.
11. The device of claim 1 , wherein the device is configured to treat gas comprising unburned hydrocarbons or volatile organic compounds.
12. The device of claim 11 , wherein the device is a catalytic converter for a vehicle.
13. A method comprising:
introducing a gas into an inlet of an emissions control device, the emissions control device comprising:
a housing comprising the inlet and an outlet;
an inductive heater disposed within the housing;
a conductive layer disposed within the housing radially outside of the inductive heater, wherein the conductive layer is gas permeable and thermally conductive; and
a catalytic layer disposed within the housing around the conductive layer, wherein the catalytic layer comprises inorganic fibers and a catalyst;
wherein the catalytic layer forms a permeable seal between the inlet and the outlet;
using the inductive heater, heating the conductive layer;
transferring heat from the conductive layer to the catalytic layer or the gas via conduction, convection, and/or radiation;
catalytically oxidizing or reducing components of the gas at the catalytic layer; and
exhausting the oxidized or reduced gas through the outlet of the emissions control device.
14. The method of claim 13 , wherein the gas comprises unburned hydrocarbons or volatile organic compounds that are oxidized or reduced at the catalytic layer.
15. The method of claim 13 , wherein the emissions control device further comprises a support layer secured radially outside and about the catalytic layer.
16. The method of claim 15 , wherein the support layer or the conductive layer comprises a catalyst.
17. The method of claim 13 , wherein the emissions control device comprises a temperature sensor proximate the catalytic layer and a controller in communication with the temperature sensor and configured to control operation of the inductive heater; and
wherein heating the conductive layer comprises intermittently operating the inductive heater via the controller to maintain a predetermined temperature range as measured by the temperature sensor.
18. The method of claim 17 , wherein the predetermined temperature range comprises a light-off temperature of a catalytic oxidation or reduction reaction occurring in the catalytically oxidizing or reducing step.
19. The method of claim 13 , wherein the emissions control device comprises a controller configured to control operation of the inductive heater; and
wherein heating the conductive layer comprises intermittently operating the inductive heater via the controller at predetermined intervals.
20. The method of claim 13 , wherein the gas is exhaust gas from a vehicle and the emissions control device is a catalytic converter.