CATALYST COMPOSITION
A catalyst composition comprising an intermetallic compound is disclosed. The intermetallic compound comprises a transition metal selected from Fe, Ce, Y, Nb and combinations thereof; and a noble metal selected from Pt, Pd, Rh and combinations thereof. The invention further relates to a washcoat comprising the catalyst composition, and a catalyst article comprising the catalyst composition, a method of treating exhaust gas with the catalyst article, a method for manufacturing the catalyst article and systems comprising the catalyst article.
1 . A catalyst composition comprising an intermetallic compound, wherein the intermetallic compound comprises:
a transition metal selected from Fe, Ce, Y, Nb and combinations thereof; and
a noble metal selected from Pt, Pd, Rh and combinations thereof.
2 . The composition according to claim 1 , wherein the intermetallic compound has a formula according to Formula I:
Al
a
-
X
b
-
PGM
c
Formula
I
in which:
a
=
100
-
b
-
c
;
25
≤
a
<
80
;
20
<
b
<
75
;
0
<
c
<
5.
wherein a, b and c are atomic weight percentages;
wherein X is the transition metal selected from Fe, Ce, Y, Nb and combinations thereof; and
wherein PGM is the noble metal selected from Pt, Pd, Rh and combinations thereof.
3 . The catalyst composition according to claim 1 , wherein the intermetallic compound has been leached prior to forming the composition.
4 . The catalyst composition according to claim 3 , wherein in the intermetallic compound has a BET surface area of about 90-160 m 2 /g.
5 . The catalyst composition according to claim 1 , wherein the transition metal is Y.
6 . The catalyst composition according to claim 1 , wherein the noble metal is Rh.
7 . The catalyst composition according to claim 1 , wherein the composition further comprises from 20 to 50 wt % of an oxygen storage component based on the total weight of the catalyst composition.
8 . The catalyst composition according to claim 1 , wherein the composition further comprises from 50 to 80 wt % of an inorganic oxide based on the total weight of the catalyst composition.
9 . A washcoat composition comprising:
a catalyst composition according to claim 1 ; and
a liquid medium.
10 . A catalyst article comprising a substrate and a catalyst composition according to claim 1 on the substrate.
11 . A catalyst article according to claim 10 , wherein the catalyst article comprises a single layer of the catalyst composition applied to the channels of the substrate.
12 . The catalyst article according to claim 10 , wherein the noble metal loading on the catalyst article is from 0.5 to 5.0 g/ft 3 .
13 . The catalyst article according to claim 10 , wherein the catalyst article is a three-way catalyst for treating a flow of a combustion exhaust gas by simultaneously oxidising carbon monoxide and hydrocarbons and reducing nitrogen oxides.
14 . A method of preparing a catalyst article according to claim 10 , comprising the step of coating a substrate with a washcoat composition according to claim 9 .
15 . An emission treatment system for treating a flow of a combustion exhaust gas comprising the catalyst article according to claim 10 .
16 . A method of treating an exhaust gas from an internal combustion engine, comprising contacting the exhaust gas with a catalyst article according to claim 10 .