Mesoporous oxide molecular sieves for absorbing nitrogen oxides

Details Mesoporous oxide molecular sieves for absorbing nitrogen oxides Mesoporous oxide molecular sieves for absorbing nitrogen oxides

1999-02-08

2000-11-14

Dunn, Tom

Chemistry of inorganic compounds

Modifying or removing component of normally gaseous mixture

Mixture is exhaust from internal-combustion engine

423212, 4232132, 4232391, 502303, 502304, 502328, 502339, 502330, 502344, B01J 2342

Patent

active

061466026

ABSTRACT:
This invention is a catalyst comprising a mesoporous aluminum oxide material including precious metal. The material is made by sol-gel techniques using a neutral surfactant with alkoxides, water and alcohol to form the aluminum oxide material having an interconnected pore structure of mesoporous size. The catalyst is useful to absorb nitrogen oxides from lean-burn engines when the exhaust gas is oxidizing, which may be gasoline or diesel engines. The nitrogen oxides are desorbed when the exhaust is made richer and is reduced over the precious metal with reductants in the gas like hydrocarbons. The alkoxides include aluminum alkoxides and at least one of alkali metal and alkaline earth metal. Preferably, the alkoxides include certain heterometallic alkoxides of aluminum and alkali metals or alkaline earth metals. Optionally, the alkoxides may also include lanthanides. Preferably, the alcohol used to make the oxide has four carbon atoms, most preferably being sec-butanol.

REFERENCES:
patent: 5242883 (1993-09-01), Ichikawa et al.
patent: 5403807 (1995-04-01), Narula
patent: 5795559 (1998-08-01), Pinnavaia et al.
patent: 5851501 (1998-12-01), Krutzsch et al.
patent: 5874057 (1999-02-01), Deeba et al.
patent: 5922293 (1999-07-01), Miyoshi et al.
patent: 6001319 (1999-12-01), Yokoi et al.
patent: 6010673 (2000-01-01), Kanazawa et al.
patent: 6027706 (2000-02-01), Pinnavaia et al.
Disclosed Anonymously, 398/Research Disclosure-Jun. 1997, "Heterometallic Alkoxides as Precursors for the Incorporation of Lanthanides in Alumina Molecular Sieves", No. 39825.
Wenzhong Zhang and Thomas J. Pinnavaia, "Rare Earth Stabilization of Mesoporous Alumina Molecular Sieves Assembled Through an N.sup.o I.sup.o Pathway", Department of Chemistry and Center for Fundamental Materials Research, Michigan State University, East Lansing MI 48824-1322, USA, p. 1185-1186 (1998) Chem. Commun.
M. Eswaramoorthy, Neeraj and C. N. R. Rao, "High Catalytic Efficiency of Transition Metal Complexes Encapsulated in a Cubic Mesoporous Phase", Chemistry and Physics of Materials Unit, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur Post, Bangalore 560 064, India, p. 615-616 (1998) Chem. Commun.
Mitsunori Yada, Masahumi Ohya, Masato Machida and Tsuyoshi Kijima, "Synthesis of Porous Yttrium Aluminium Oxide Templated by Dodecyl Sulfate Assemblies", Department of Materials Science, Faculty of Engineering, Miyazaki University, Miyazaki 889-2192, Japan, p. 1941-1942 (1998) Chem. Commun.

Affiliated with

Also associated with

Rating

Mesoporous oxide molecular sieves for absorbing nitrogen oxides does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Mesoporous oxide molecular sieves for absorbing nitrogen oxides , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Mesoporous oxide molecular sieves for absorbing nitrogen oxides will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2062185