Catalyst body

• US 20010044376A1
• Filed: 12/14/2000
• Published: 11/22/2001
• Est. Priority Date: 12/17/1999
• Status: Active Grant

• Current Assignee: NGK Insulators Limited
• Original Assignee: NGK Insulators Limited
• Inventors: Suzuki, Junichi, Noda, Naomi, Harada, Takashi
• Granted Patent: US 7,576,028 B2
• Time in Patent Office: Days
• US Class Current: 502/206
• CPC Class Codes: B01D 2255/1021 Platinum
• CPC Class Codes: B01D 2255/1023 Palladium
• CPC Class Codes: B01D 2255/1025 Rhodium
• CPC Class Codes: B01D 2255/202 Alkali metals
• CPC Class Codes: B01D 2255/2022 Potassium
• CPC Class Codes: B01D 2255/2025 Lithium
• CPC Class Codes: B01D 2255/2027 Sodium
• CPC Class Codes: B01D 2255/204 Alkaline earth metals
• CPC Class Codes: B01D 2255/20707 Titanium
• CPC Class Codes: B01D 2255/20784 Chromium
• CPC Class Codes: B01D 53/9422 for removing nitrogen oxides by NOx storage or reduction by cyclic switching between lean and rich exhaust gases (LNT, NSC, NSR)
• CPC Class Codes: B01J 23/58 with alkali- or alkaline earth metals
• CPC Class Codes: B01J 37/0203 the impregnation liquid containing organic compounds
• CPC Class Codes: B01J 37/0215 Coating

Abstract

A catalyst body comprising a carrier and a catalyst layer containing an alkali metal and/or an alkaline earth metal, loaded on the carrier, which catalyst further contains a substance capable of reacting with the alkali metal and/or the alkaline earth metal, dominating over the reaction between the main components of the carrier and the alkali metal and/or the alkaline earth metal. With this catalyst body, the deterioration of the carrier by the alkali metal and/or the alkaline earth metal is prevented; therefore, the catalyst body can be used over a long period of time.

Claims

1. A catalyst body comprising a carrier and a catalyst layer containing an alkali metal and/or an alkaline earth metal, loaded on the carrier, which catalyst further contains a substance capable of reacting with the alkali metal and/or the alkaline earth metal, dominating over reaction between main components of the carrier and the alkali metal and/or the alkaline earth metal.

2. A catalyst body according to

claim 1

, wherein the substance capable of reacting with the alkali metal and/or the alkaline earth metal, dominating over the reaction between the main components of the carrier and the alkali metal and/or the alkaline earth metal is at least one kind of substances selected from the group consisting of B, Al, Si, P, S, Cl, Ti, V, Cr, Mn, Ga, Ge, As, Se, Br, Zr, Mo, Sn, Sb, I and W.

3. A catalyst body according to

claim 1

, wherein the catalyst layer further contains at least one kind of noble metals selected from the group consisting of Pt, Pd and Rh.

4. A catalyst body according to

claim 1

, wherein the substance capable of reacting with the alkali metal and/or the alkaline earth metal, dominating over the reaction between the main components of the carrier and the alkali metal and/or the alkaline earth metal is contained in the carrier.

5. A catalyst body according to

claim 1

, wherein the substance capable of reacting with the alkali metal and/or the alkaline earth metal, dominating over the reaction between the main components of the carrier and the alkali metal and/or the alkaline earth metal is contained in the catalyst layer.

6. A catalyst body according to

claim 1

, wherein a layer of the substance capable of reacting with the alkali metal and/or the alkaline earth metal, dominating over the reaction between the main component of the carrier and the alkali metal and/or the alkaline earth metal is formed between the carrier and the catalyst layer.

7. A catalyst body according to

claim 1

, wherein the carrier is a honeycomb carrier.

8. A catalyst body according to

claim 1

, wherein the main component of the carrier is cordierite.