Title:
窒素酸化物浄化触媒及び窒素酸化物浄化方法
Document Type and Number:
Japanese Patent JP5309936
Kind Code:
B2
Abstract:
To provide a ferric silicate catalyst being capable of converting nitrogen oxides efficiently over a wide temperature range from low to high temperatures and having high hydrothermal durability, and to provide a method of converting nitrogen oxides using the catalyst.
The catalyst consists of a crystalline silicate or an aluminosilicate containing iron in the β structure. For the β ferric silicate of a SiO2/Fe2O3mol ratio of 20-300 and a log(SiO2/Al2O3) of ≥2, the catalyst uses at least one reducing agent selected from ammonia, urea and organic amines so as to exert high performance of reducing nitrogen oxides in exhaust gas selectively, especially a high activity after a durability treatment at low temperatures of ≤250°C. The iron in the β ferric silicate is preferably an isolated ferric ion having a symmetric tetrahedral structure confirmable by UV/visible absorption spectrometry and electron spin resonance measurement.
COPYRIGHT: (C)2009,JPO&INPIT
Inventors:
Yusuke Naragi
Ariga Ko
Hidekazu Aoyama
Application Number:
JP2008309425A
Publication Date:
October 09, 2013
Filing Date:
December 04, 2008
Assignee:
Tosoh Corporation
International Classes:
B01J29/76; B01D53/94; F01N3/28
Domestic Patent References:
| JP4957176B2 | | | | |
| JP10259018A | | | | |
| JP2007076990A | | | | |
| JP2293021A | | | | |
| JP2002160915A | | | | |
