Exhaust treatment device having a reactive compound and conditioning the device via endothermic reaction

• US 8,091,337 B2
• Filed: 02/29/2008
• Issued: 01/10/2012
• Est. Priority Date: 02/29/2008
• Status: Active Grant

• Current Assignee: Corning Incorporated
• Original Assignee: Corning Incorporated
• Inventors: Tepesch, Patrick David
• Primary Examiner(s): Tran, Binh Q
• Application Number:
  US12/074,142
• Publication Number:
  US 20090217648A1
• Time in Patent Office: 1,411 Days
• Field of Search: 602/74, 602/76, 602/86, 602/99, 603/00, 602/95, 603/11
• US Class Current: 60/274
• CPC Class Codes: B01D 2279/30 for treatment of exhaust gases from IC Engines
• CPC Class Codes: B01D 46/84 by heating only
• CPC Class Codes: F01N 2240/10 a heat accumulator
• CPC Class Codes: F01N 2250/10 cooling and filtering
• CPC Class Codes: F01N 3/023 using means for regenerating the filters, e.g. by burning trapped particles by electrically controlling the supply of combustible mixture or its constituents only F02D41/0235
• CPC Class Codes: F01N 3/2006 Periodically heating or cooling catalytic reactors, e.g. at cold starting or overheating by electrically controlling the supply of combustible mixture or its constituents only F02D41/0235
• CPC Class Codes: F01N 5/02 the devices using heat
• CPC Class Codes: Y02T 10/12 Improving ICE efficiencies

Abstract

An exhaust treatment device and a method of conditioning the device that include a reactive compound capable of undergoing an endothermic reaction are described. A method of manufacturing the device is also disclosed.

Claims

1. A method of conditioning an exhaust treatment device exposed to an exhaust stream, the method comprising:

contacting the device with the exhaust stream;

initiating an exothermic chemical reaction within the device, thereby generating heat and causing passive or active regeneration to occur; and

initiating an endothermic chemical reaction within the device during passive or active regeneration, wherein the endothermic chemical reaction absorbs at least part of the heat generated by the exothermic chemical reaction.

2. The method of claim 1 wherein the exothermic chemical reaction comprises reacting exhaust particulates trapped in the device, wherein the exhaust particulates were removed from the exhaust stream.

3. The method of claim 1 wherein the device is a particulate filter or a flow-through substrate.

4. The method of claim 1, wherein the heat from the exothermic chemical reaction initiates the endothermic chemical reaction.

5. The method of claim 1, wherein the endothermic chemical reaction has a heat of reaction of at least about 1.25 kJ/g or at least about 2 kJ/cc.

6. The method of claim 1, wherein the exhaust treatment device comprises a reactive compound is selected from a group consisting of CaCO₃, CaSO₄, MgSO₄, metal salt hydrates, and combinations thereof.

7. The method of claim 6, wherein the device is comprised of at least 20 vol % of the reactive compound.

8. The method of claim 1, wherein initiating the exothermic chemical reaction comprises releasing an accelerant into the exhaust stream.

9. The method of claim 1 wherein the endothermic chemical reaction is reversible.

10. The method of claim 1, wherein the endothermic chemical reaction comprises decomposing the reactive compound into a plurality of products.

11. The method of claim 10, wherein at least one product includes a gas selected from a group consisting of CO, CO₂, SO₂, H₂O, O₂ and mixtures thereof.

12. The method of claim 10, further comprising recovering at least part of the reactive compound from the plurality of products.

13. The method of claim 1, wherein the endothermic chemical reaction is irreversible.

14. The method of claim 1, wherein the endothermic chemical reaction occurs between about 700 and 1000°

C.

15. The method of claim 1, wherein the ratio of the heat absorbed by the endothermic chemical reaction plus the integral of the heat capacity of the device taken from 600°

C. to 1000°

C. divided by the integral of the heat capacity of the device taken from 600°

C. to 1000°

C. is greater than 2.

16. The method of claim 9, wherein the reverse reaction occurs after regeneration.