Methanol
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4.2.5 Fuel Cell Fuel
Methanol can also be used in fuel cells—for fuel cell vehicles—which are
considered to be the best alternative to internal combustion engines in the
transportation field. One of the most efficient uses of methanol is in fuel
cells, particularly in direct methanol fuel cells (DMFC), in which methanol
is directly oxidized with air to carbon dioxide (CO 2 ) and H 2 O while producing electricity (Olah and Prakash 2009). DMFC systems are currently
being developed as battery replacements for the portable power market.
With the exception of compressed hydrogen and the DMFC, all fuel cell
vehicle designs require some kind of steam reforming or partial oxidation
to release the hydrogen in the fuel. These processes can create NO x emissions that, even in very small quantities, can compromise air quality when
multiplied by millions of vehicles in use. NO x is an essential precursor to
the formation of ground level ozone, or smog. Because the DMFC breaks
methanol into hydrogen and oxygen directly without requiring steam
reforming or partial oxidation, there are no NO x emissions from the vehicle
(Nowell 2009).
4.3 Methanol Production
Methanol is one of the top 10 chemicals produced globally (Huber, Lborra,
and Corma 2006) because it can be produced from various feedstocks, including fossil fuels (e.g., natural gas, crude oil, coal) and renewable resources
(e.g., wood and municipal solid wastes).
4.3.1 Methanol Production Via Synthesis gas
Synthesis gas can be used as a feedstock for a range of products including
methanol. Methanol production via synthesis gas depends on the feedstock of choice in varying proportions. The synthesis gas may come from
any number of different routes, including coal gasification, partial oxidation
of heavy oils, steam reforming of natural gas (with or without CO 2 injection), steam reforming of LPG feedstocks and naphtha, combined or oxygenenhanced reforming, and heat-exchange reforming. This list names the
principal routes by which methanol synthesis gas may be produced (Cheng
and Kung 1994).
Methanol was first produced as a by-product in the manufacture of charcoal
through the destructive distillation of wood, with yields of 12–24 litter per
ton of wood (National Research Council 1983). Methanol can be produced in
a number of different ways, but currently most of the methanol produced is
from natural gas. The gas is first compressed and then purified by removing
85
4.2.5 Fuel Cell Fuel
Methanol can also be used in fuel cells—for fuel cell vehicles—which are
considered to be the best alternative to internal combustion engines in the
transportation field. One of the most efficient uses of methanol is in fuel
cells, particularly in direct methanol fuel cells (DMFC), in which methanol
is directly oxidized with air to carbon dioxide (CO 2 ) and H 2 O while producing electricity (Olah and Prakash 2009). DMFC systems are currently
being developed as battery replacements for the portable power market.
With the exception of compressed hydrogen and the DMFC, all fuel cell
vehicle designs require some kind of steam reforming or partial oxidation
to release the hydrogen in the fuel. These processes can create NO x emissions that, even in very small quantities, can compromise air quality when
multiplied by millions of vehicles in use. NO x is an essential precursor to
the formation of ground level ozone, or smog. Because the DMFC breaks
methanol into hydrogen and oxygen directly without requiring steam
reforming or partial oxidation, there are no NO x emissions from the vehicle
(Nowell 2009).
4.3 Methanol Production
Methanol is one of the top 10 chemicals produced globally (Huber, Lborra,
and Corma 2006) because it can be produced from various feedstocks, including fossil fuels (e.g., natural gas, crude oil, coal) and renewable resources
(e.g., wood and municipal solid wastes).
4.3.1 Methanol Production Via Synthesis gas
Synthesis gas can be used as a feedstock for a range of products including
methanol. Methanol production via synthesis gas depends on the feedstock of choice in varying proportions. The synthesis gas may come from
any number of different routes, including coal gasification, partial oxidation
of heavy oils, steam reforming of natural gas (with or without CO 2 injection), steam reforming of LPG feedstocks and naphtha, combined or oxygenenhanced reforming, and heat-exchange reforming. This list names the
principal routes by which methanol synthesis gas may be produced (Cheng
and Kung 1994).
Methanol was first produced as a by-product in the manufacture of charcoal
through the destructive distillation of wood, with yields of 12–24 litter per
ton of wood (National Research Council 1983). Methanol can be produced in
a number of different ways, but currently most of the methanol produced is
from natural gas. The gas is first compressed and then purified by removing