Catalysts for natural gas processes
Catalysts, catalytic forms and formulations, and catalytic methods are provided. The catalysts and catalytic forms and formulations are useful in a variety of catalytic reactions, for example, the oxidative coupling of methane. Related methods for use and manufacture of the same are also disclosed.
1. A formed catalytic material comprising:
(a) a perovskite; and
(b) a catalyst having the following formula:
Ln1 a Ln 2 b O x (OH) y
wherein:
Ln1and Ln2 are each independently different lanthanide elements;
O is oxygen;
OH is hydroxy;
a is a number greater than 0; and
b, x and y are each independently numbers of 0 or greater, provided that at least one of x or y is greater than 0, and
wherein:
the catalytic material further comprises a methane conversion of greater than 20% and a C2 selectivity of greater than 50% when the catalyst is employed as a heterogeneous catalyst in the oxidative coupling of methane at a temperatures ranging from about 550° C. to about 750° C.
2. The catalytic material of claim 1 , wherein the perovskite comprises the following formula:
E 1 α E 2 β E 3 χ A m B n O p ,
wherein:
A is a lanthanide or an element from group 4
B is an element from group 2;
E 1 , E 2 and E 3 are each independently an element from groups 2, 3, 4 or the lanthanides;
O is oxygen;
α, β, χ are each independently a number of 0 or greater; and
m, n and p are each independently numbers greater than 0.
3. The catalytic material of claim 2 , wherein B is Ba, Sr or Ca.
4. The catalytic material of claim 2 , wherein A is Ce, Ti, Zr or Hf.
5. The catalytic material of claim 2 , wherein α is greater than 0.
6. The catalytic material of claim 5 , wherein the perovskite has the following formula:
E 1 α A m B n O p .
7. The catalytic material of claim 2 , wherein E l is an element from group 2 or group 3 of the periodic table.
8. The catalytic material of claim 2 , wherein the perovskite has the formula ABO 3 .
9. The catalytic material of claim 1 , wherein x is greater than zero.
10. The catalytic material of claim 1 , wherein b and y are both 0.
11. The catalytic material of claim 1 , wherein the catalyst is a nanostructured catalyst.
12. The catalytic material of claim 11 , wherein the catalyst is a nanowire catalyst.
13. The catalytic material of claim 1 , wherein the catalyst further comprises a dopant selected from one or more elements from groups 2, 6 and the lanthanides.
14. The catalytic material of claim 13 , wherein the catalyst further comprises a dopant from each of groups 2, 6 and the lanthanides.
15. The catalytic material of claim 13 , wherein the catalyst further comprises a dopant from each of groups 2 and 6.