Title:
AUTOMOBILE EXHAUST GAS PURIFYING CATALYST AND METHOD FOR PRODUCING THE SAME
Document Type and Number:
WIPO Patent Application WO/2008/054026
Kind Code:
A1
Abstract:
Disclosed is an automobile exhaust gas purifying catalyst wherein Rh as a catalyst metal
is supported by a carrier mainly composed of ZrO2. This automobile exhaust
gas purifying catalyst is prevented from sintering of the carrier, while being
improved in supporting efficiency and low temperature activity. Also disclosed
is a method for producing such a catalyst. Specifically disclosed is an automobile
exhaust gas purifying catalyst wherein Rh as a catalyst metal is supported, in
the form of particles, by a carrier mainly composed of ZrO2 which is
fired under such conditions that as-fired ZrO2 is not substantially charged
in a process liquid for catalyst metal loading. A method for producing such an
automobile exhaust gas purifying catalyst comprises a step for electrostatically charging
a carrier mainly composed of ZrO2 fired under the above-mentioned conditions
by subjecting the carrier to at least one of an acid treatment and a base treatment,
and another step for having the carrier adsorb Rh colloid by immersing the electrostatically
charged carrier into the process liquid for catalyst metal loading which contains
colloid of Rh as a catalyst metal.
Inventors:
TAKESHIMA SHINICHI (JP)
KOYAMA AKIO (JP)
KOYAMA AKIO (JP)
Application Number:
PCT/JP2007/071671
Publication Date:
May 08, 2008
Filing Date:
November 01, 2007
Export Citation:
Assignee:
TOYOTA MOTOR CO LTD (JP)
TAKESHIMA SHINICHI (JP)
KOYAMA AKIO (JP)
TAKESHIMA SHINICHI (JP)
KOYAMA AKIO (JP)
International Classes:
B01J23/46; B01D53/94; B01J35/10; B01J37/02; F01N3/10
Domestic Patent References:
| WO2005082782A2 | 2005-09-09 | |||
| WO1999032223A1 | 1999-07-01 |
Foreign References:
| JP2006137651A | 2006-06-01 | |||
| JPH04135641A | 1992-05-11 | |||
| JPH04166228A | 1992-06-12 | |||
| JP2006068665A | 2006-03-16 | |||
| JP2004261641A | 2004-09-24 | |||
| JPH04219140A | 1992-08-10 | |||
| JP2002282692A | 2002-10-02 | |||
| JP2000279818A | 2000-10-10 | |||
| JP2000279824A | 2000-10-10 | |||
| JP2005296733A | 2005-10-27 | |||
| JP2004082000A | 2004-03-18 | |||
| JP2005279435A | 2005-10-13 |
Other References:
C. WONG; R. W. MCCABE, JOURNAL OF CATALYSIS, vol. 119, 1989, pages 47 - 64
See also references of EP 2078560A4
See also references of EP 2078560A4
Attorney, Agent or Firm:
AOKI, Atsushi et al. (Toranomon 37 Mori Bldg.5-1, Toranomon 3-chom, Minato-ku Tokyo 23, JP)
Download PDF: