Catalysts for petrochemical catalysis
Metal oxide catalysts comprising various dopants are provided. The catalysts are useful as heterogenous catalysts in a variety of catalytic reactions, for example, the oxidative coupling of methane to C2 hydrocarbons such as ethane and ethylene. Related methods for use and manufacture of the same are also disclosed.
1. A method for the oxidative coupling of methane, the method comprising contacting methane with a catalyst at temperatures ranging from about 550° C. to about 750° C., thereby converting the methane to C2 hydrocarbons at a methane conversion of greater than 20% and a C2 selectivity of greater than 50%, wherein the catalyst comprises the following formula:
ABO 3 ;
wherein:
A is an element from the lanthanides or groups 2, 3 or 4 of the periodic table;
B is an element from groups 4, 12 or 13 of the periodic table or Ce, Eu, Gd, Tb or Ho; and
O is oxygen,
the catalyst further comprising one or more dopant from any one of groups 2 or 3, and provided that A and B are not the same.
2. The method of claim 1 , wherein the method produces a product gas comprising less than 0.5% carbon monoxide.
3. The method of claim 1 , wherein A is from groups 2, 3 or 4.
4. The method of claim 1 , wherein A is Ce, Pr, Sr, Ca, Mg, Y, Zr or Ba.
5. The method of claim 1 , wherein B is from group 4.
6. The method of claim 1 , wherein B is Zr or Hf.
7. The method of claim 1 , wherein the dopant is Sr, Mg or Ca.
8. The method of claim 1 , wherein the catalyst comprises one of the following formulas: Y/SrZrO 3 , SrHfO 3 , SrZrO 3 , Mg/SrHfO 3 , CaHfO 3 or SrTbO 3 .
9. The method of claim 1 , wherein the catalyst is a bulk catalyst.
10. The method of claim 1 , wherein the catalyst is a nanostructured catalyst.
11. The method of claim 10 , wherein the catalyst is a nanowire.