Res. Chem. Intermed.
, Vol. 32, No. 3–4, pp. 263–278 (2006)
Also available online - www.vsppub.com
Formation of pure hydrogen from methane
Department of Applied Chemistry, Graduate School of Science and Engineering,
Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo 152-8552, Japan
Received 4 January 2005; accepted 25 February 2005
Abstract—The methods for production of pure hydrogen from methane are summarized. One method
is methane decomposition to hydrogen and carbon nanoﬁbers. Ni-based catalysts with high activity
and long life for the methane decomposition were developed. The other method is based on the redox
of iron oxides, i.e., Fe
is reduced with methane to iron metals and, subsequently, iron metals are
oxidized with water vapor to form hydrogen. Iron oxide mediators that could be reduced with methane
and subsequently be oxidized with water vapor at low temperatures were designed.
Keywords: Hydrogen; iron oxide; methane decomposition; Ni-based catalysts.
Hydrogen is regarded as one of candidates for a clean energy source that can be
used as a substitute for fossil fuels in order to solve many environmental problems.
fuel cell, such as a polymer electrolyte fuel cell (PEFC), is a promising
system to utilize hydrogen with high efﬁciency. PEFC can convert chemical energy
of hydrogen into electricity directly through chemical reaction between hydrogen
and oxygen. PEFC does not emit any pollutant gases, such as NO
it can operate at low temperatures. The production of hydrogen through water
splitting by sunlight or by renewable energy sources such as wind power, tidal
power and others is an ideal method, since water can be regarded as a recycle
energy source in this case. However, the production of hydrogen from water would
not be realized in near future due to high renewable energy costs. The author
believes that one of the realistic methods for production of hydrogen is to utilize
methane, a main component of natural gas, because methane has the highest H/C
ratio of all hydrocarbons and it is the most abundant resource. In fact, hydrogen
has been produced from methane through steam reforming. However, CO and CO