Phase Stability of Lanthanum-Manganese Perovskite in the Mixture of Metal Oxides

• US 20150182954A1
• Filed: 03/13/2015
• Published: 07/02/2015
• Est. Priority Date: 06/06/2013
• Status: Abandoned Application

• Current Assignee: Clean Diesel Technologies, Inc.
• Original Assignee: Clean Diesel Technologies, Inc.
• Inventors: Nazarpoor, Zahra, Golden, Stephen J.
• Application Number:
  US14/657,812
• Publication Number:
  US 20150182954A1
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B01D 2255/2063 Lanthanum
• CPC Class Codes: B01D 2255/2073 Manganese
• CPC Class Codes: B01D 2255/402 Perovskites
• CPC Class Codes: B01D 2255/65 Catalysts not containing noble metals
• CPC Class Codes: B01D 2258/012 Diesel engines and lean burn gasoline engines
• CPC Class Codes: B01D 53/944 Simultaneously removing carbon monoxide, hydrocarbons or carbon making use of oxidation catalysts three-way-catalysts [TWC] B01D53/9445
• CPC Class Codes: B01J 23/002 Mixed oxides other than spinels, e.g. perovskite
• CPC Class Codes: B01J 23/34 Manganese
• CPC Class Codes: B01J 2523/00 Constitutive chemical elements of heterogeneous catalysts
• CPC Class Codes: B01J 2523/25 Barium
• CPC Class Codes: B01J 2523/3706 Lanthanum
• CPC Class Codes: B01J 2523/3712 Cerium
• CPC Class Codes: B01J 2523/3718 Praseodymium
• CPC Class Codes: B01J 2523/48 Zirconium
• CPC Class Codes: B01J 2523/56 Niobium
• CPC Class Codes: B01J 2523/72 Manganese
• CPC Class Codes: B01J 29/06 Crystalline aluminosilicate zeolites; Isomorphous compounds thereof
• CPC Class Codes: B01J 35/19 Catalysts containing parts with different compositions
• CPC Class Codes: B01J 37/03 Precipitation; Co-precipitation
• CPC Class Codes: B01J 37/04 Mixing B01J37/0009, B01J37/0018 take precedence
• CPC Class Codes: B01J 37/08 : Heat treatment B01J37/0009, B01J37/0018 take precedence
• CPC Class Codes: G01N 23/2076 : for spectrometry, i.e. using an analysing crystal, e.g. for measuring X-ray fluorescence spectrum of a sample with wavelength-dispersion, i.e. WDXFS

Abstract

The present disclosure describes ZPGM material compositions including LaMnO₃ perovskite structure mixed with a plurality of support oxide powders to develop suitable ZPGM catalyst materials. Bulk powder ZPGM catalyst compositions are produced by physically mixing bulk powder LaMnO₃ perovskite with different support oxide powders calcined at about 1000° C. XRD analyses are performed for bulk powder ZPGM catalyst compositions to determine La—Mn perovskite phase formation and phase stability for a plurality of temperatures to about 1000° C. ZPGM catalyst material compositions including La—Mn perovskite structure mixed with doped zirconia, La₂O₃, cordierite, and ceria-zirconia support oxides present phase stability, which can be employed in ZPGM catalysts for a plurality of DOC applications, thereby leading to a more effective utilization of ZPGM catalyst materials with high thermal and chemical stability in DOC products.

Claims

1. A composition comprising a catalyst comprising LaMnO₃ perovskite in weight ratio of about 1:

1 to an oxide powder selected from the group consisting of ZrO₂—

Pr₆O₁₁, Nb₂O₅, BaO, La₂O₃, CeO₂—

ZrO₂, cordierite, or mixtures thereof.

2. The composition of claim 1, wherein the ceria-zirconia comprises 75% CeO₂.

3. The composition of clam 1, wherein the catalyst is calcined at about 1000°

C.

4. A heat stable catalyst composition comprising LaMn perovskite on a support oxide of La₂O₃.

5. The composition of clam 4, wherein the catalyst is calcined at about 1000°

C.

6. A catalyst comprising a mixture of LaMnO₃, Nb₃O₅, and LaNbO₄, wherein the mixture results from the calcination of LaMn perovskite on a support oxide of NbO₃.

7. The composition of clam 6, wherein the catalyst is calcined at about 1000°

C.

8. A method for determining the phase stability of bulk La—

Mn perovskite in selected support oxides, comprising;

providing a mixture comprising LaMnO₃ perovskite and a plurality of metals; and

analyzing the mixture using x-ray diffraction to produce a graph having at least one defined peak;

wherein at least one defined peak is representative of a stable LaMnO₃ perovskite and metal combination.

9. The method of claim 8, wherein at least one of the at least one defined peak represents a composition comprising LaMnO₃ perovskite in weight ratio of about 1:

1 to an oxide powder selected from the group consisting of ZrO₂—

Pr₆O₁₁, Nb₂O₅, BaO, La₂O₃, CeO₂—

ZrO₂, and cordierite.

10. The method of claim 8, wherein at least one of the at least one defined peak represents a composition comprising a mixture of LaMnO₃, Nb₃O₅, and LaNbO₄, wherein the mixture results from the calcination of LaMn perovskite on a support oxide of NbO₃.

11. The method of claim 10, wherein the calcination is at about 1000°

C.

12. The method of claim 8, wherein at least one of the at least one defined peak represents a composition comprising LaMn perovskite on a support oxide of La₂O₃.