Title:
CE-ZR COMPOSITE OXIDE AND EXHAUST GAS CLEANING CATALYST USING SAME
Document Type and Number:
WIPO Patent Application WO/2021/251000
Kind Code:
A1
Abstract:
The purpose of the present invention is to provide a means for suppressing a decrease in oxygen storage and release performance, which is caused by long-term exposure to exhaust gases, in a Ce-Zr composite oxide. Provided is a Ce-Zr composite oxide which contains cerium and zirconium and in which the cerium atom uneven distribution rate is 1.80 or less. Also provided is a method for producing a Ce-Zr composite oxide, the method including: an acid treatment step in which at least one type of acid selected from the group consisting of sulfuric acid, nitric acid and hydrochloric acid is brought into contact with the surface of a raw material composite oxide containing cerium and zirconium at quantities such that the amount of the acid is 4-28 parts by mass relative to 100 parts by mass of the raw material composite oxide; and a firing step in which the treated composite oxide obtained in the acid treatment step is fired for 5-300 minutes at a temperature of 400-1200ºC. In the acid treatment step, the acid is brought into contact with the surface of the raw material composite oxide while the acid is in the form of an aqueous solution. The concentration of the acid in the aqueous solution is 15-80 mass%.
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Inventors:
FUJINO DAISHI (JP)
Application Number:
PCT/JP2021/015846
Publication Date:
December 16, 2021
Filing Date:
April 19, 2021
Export Citation:
Assignee:
UMICORE SHOKUBAI JAPAN CO LTD (JP)
International Classes:
C01G25/00; B01D53/94; B01J23/63; B01J32/00; B01J37/02; F01N3/10; F01N3/28
Domestic Patent References:
| WO2016158656A1 | 2016-10-06 |
Foreign References:
| JPH10202102A | 1998-08-04 | |||
| JP2020059630A | 2020-04-16 | |||
| JP2004002147A | 2004-01-08 | |||
| JP2020100958A | 2020-07-02 |
Other References:
DE RIVAS, B. ET AL.: "Impact of induced chlorine-poisoning on the catalytic behaviour of Ce0.5Zr0.502 and Ce0.15Zr0.85O2 in the gas-phase oxidation of chlorinated VOCs", APPLIED CATALYSIS B: ENVIRONMENTAL, vol. 104, 2011, pages 373 - 381, XP028202466, DOI: http://dx.doi.org/10.1016/j.apcatb. 2011.03.00 3, 2
DE RIVAS, B. ET AL.: "Promoted activity of sulphated Ce/Zr mixed oxides for chlorinated VOC oxidative abatement", APPLIED CATALYSIS B: ENVIRONMENTAL, vol. 129, 2013, pages 225 - 235, XP055890527, DOI: 10.1016/j.apcatb.2012.09.026
DE RIVAS, B. ET AL.: "Promoted activity of sulphated Ce/Zr mixed oxides for chlorinated VOC oxidative abatement", APPLIED CATALYSIS B: ENVIRONMENTAL, vol. 129, 2013, pages 225 - 235, XP055890527, DOI: 10.1016/j.apcatb.2012.09.026
Attorney, Agent or Firm:
HATTA & ASSOCIATES (JP)
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