HYDROGEN GENERATION
A process for the decomposition of methane can be controlled to form ethane or hydrogen with a solid carbon product.
1 . A method of selectively producing hydrogen or ethane from methane comprising:
selecting a temperature suitable for a metal catalyst and a feed gas including methane to produce a product having a controlled hydrogen/ethane ratio, predominately hydrogen and a solid carbon product or predominately ethane and hydrogen;
contacting the feed gas with the metal catalyst at the selected temperature to produce the product.
2 . The method of claim 1 , wherein the selected temperature is a temperature suitable to produce a product having a hydrogen/ethane ratio of at least 3.
3 . The method of claim 1 , wherein the selected temperature is a temperature suitable to produce a product having a hydrogen/ethane ratio of at least 5.
4 . The method of claim 1 , wherein the selected temperature is a temperature suitable to produce a product gas having a hydrogen/ethane ratio of at least 25.
5 . The method of claim 1 , wherein the selected temperature is a temperature suitable to produce a product gas having a hydrogen/ethane ratio of at least 250.
6 . The method of claim 1 , wherein the selected temperature is a temperature suitable to produce a product gas having a hydrogen/ethane ratio of at least 600.
7 . The method of claim 1 , wherein the selected temperature is less than 1000° C.
8 . The method of claim 1 , wherein the selected temperature is less than 800° C.
9 . The method of claim 1 , wherein the selected temperature is greater than 300° C.
10 . The method of claim 1 , wherein the metal catalyst includes ruthenium, nickel, iron, copper, cobalt, palladium, platinum, or combinations thereof.
11 . The method of claim 1 , wherein the metal catalyst is supported on a solid support.
12 . The method of claim 11 , wherein the solid support includes a silicon oxide, aluminum oxide, titanium oxide, zirconium oxide, magnesium oxide, cerium oxide, zinc oxide, molybdenum oxide, iron oxide, nickel oxide, cobalt oxide or graphite.
13 . The method of claim 1 , further comprising separating the hydrogen from the solid carbon product.
14 . The method of claim 1 , wherein the feed gas comprises less than 1000 ppm water.
15 . The method of claim 1 , wherein the feed gas consists essentially of methane and an inert gas.
16 . The method of claim 1 , wherein the feed gas includes less than 1000 ppm oxygen containing compounds.
17 . The method of claim 1 , wherein selecting the temperature includes choosing a first temperature for the metal catalyst and the feed gas to produce a product gas consisting essentially of hydrogen or a second temperature for the metal catalyst and the feed gas to produce a product gas consisting essentially of ethane and hydrogen.
18 . A method of producing hydrogen comprising contacting a feed gas including methane with a ruthenium nanoparticle on a silica nanoparticle support at a temperature suitable to produce a product gas including hydrogen.
19 . A method of selectively producing hydrogen or ethane comprising selecting a first pressure and a first temperature suitable to produce hydrogen from methane or a second pressure and a second temperature suitable to produce ethane from methane and contacting a feed gas including methane with a metal catalyst at the selected temperature and selected pressure to produce a product gas including hydrogen or ethane.