Catalyst and method for converting natural gas to higher carbon compounds
A catalyst composition and process facilitates the oxidative reforming of low molecular weight hydrocarbons, such as methane, to other hydrocarbons having 2 or more carbon atoms (“C 2+ compounds”). Compositions having a formula comprising a metal, tungsten, manganese and oxygen effectively catalyze the oxidative reforming of methane with a high rate of conversion and selectivity. Controlling feed gas flow and catalyst bed temperature controls the exothermic OCM reaction, avoiding runaway reactions or coking. A single or multiple reactor system can be utilized for the oxidative reforming reactions. Using two reactors in series, catalyst embodiments produced favorable yields of C 2+ compounds, in the presence or absence of a distributed oxygen feed, and with or without interstage effluent cooling. Removal of desirable end products from the reactor effluent, followed by recycling of the residual effluent, increases the conversion to, and ultimate yield of desirable end product.
1. A composition for the oxidative reforming of hydrocarbons, the composition comprising:
a catalyst having the formula M 1 , W, Mn O x wherein
M 1 is cobalt, and the cobalt comprises from about 0.03 mol to about 1 mol;
W is tungsten, and W comprises from about 0.01 mol to less than about 2 mol;
Mn is manganese, and Mn comprises from about 0.3 mol to less than 3 mol;
O is oxygen; and
X is a quantity from about 0.1 to about 4.
2. The composition as described in claim 1 , wherein the cobalt comprises from about 0.2 mol to about 1 mol.
3. The composition as described in claim 2 , wherein the cobalt comprises from about 0.2 mol to about 0.3 mol.
4. The composition as described in claim 3 , wherein the tungsten comprises from about 0.1 mol to about 1 mol.
5. The composition as described in claim 1 , wherein the manganese comprises from about 0.5 mol to less than about 2 mol.
6. The composition as described in claim 4 , wherein the manganese comprises from about 0.5 mol to about 1.5 mol.
7. A composition for the oxidative reforming of hydrocarbons, the composition comprising:
a catalyst having the formula M 1 , W, Mn O x wherein
M 1 is cobalt, and the cobalt comprises from about 0.03 mol to about 0.5 mol;
W is tungsten, and W comprises from about 0.01 mol to less than about 2 mol;
Mn is manganese, and Mn comprises from about 0.3 mol to less than 3 mol;
O is oxygen; and
X is a quantity from about 0.1 to about 4.