Argonne breakthrough may revolutionize ethylene production
Scientists create environmentally friendly technology
to produce commonly used compound
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ARGONNE, Ill. (Feb. 5, 2008)—A new environmentally friendly technology created
by scientists at the U.S. Department of Energy's (DOE) Argonne National Laboratory
may revolutionize the production of the world's most commonly produced organic
compound, ethylene.
This work was funded by the Department of Energy's Industrial
Technologies Program, which resides within its Office of Energy
Efficiency & Renewable Energy (EERE). EERE's mission
is to strengthen America's energy security, environmental quality, and
economic vitality in public-private partnerships that: enhance energy
efficiency and productivity; bring clean, reliable and affordable energy
technologies to the marketplace; and make a difference in the everyday
lives of Americans by enhancing their energy choices and their quality
of life. |
An Argonne research team led by senior ceramist Balu Balachandran devised
a high-temperature membrane that can produce ethylene from an ethane stream
by removing pure hydrogen. “This is a clean, energy-efficient way of producing
a chemical that before required methods that were expensive and wasteful and
also emitted a great deal of pollution,” Balachandran said.
Ethylene has a vast number of uses in all aspects of industry. Farmers and
horticulturalists use it as a plant hormone to promote flowering and ripening,
especially in bananas. Doctors and surgeons have also long used ethylene as
an anesthetic, while ethylene-based polymers can be found in everything from
freezer bags to fiberglass.
Because the new membrane lets only hydrogen pass through it, the ethane stream
does not come into contact with atmospheric oxygen and nitrogen, preventing
the creation of a miasma of greenhouse gases—nitrogen oxide, carbon dioxide
and carbon monoxide—associated with the traditional production of ethylene
by pyrolysis, in which ethane is exposed to jets of hot steam. The world's
ethylene producers manufacture more than 75 million metric tons of ethylene
per year, causing millions of metric tons' worth of greenhouse gas emissions.
Unlike pyrolysis, which requires the constant input of heat, the hydrogen
transport membrane produces the fuel needed in order to drive the reaction.
By using air on one side of the membrane, the already-transported hydrogen
can react with oxygen to provide energy. “By using this membrane, we essentially
enable the reaction to feed itself,” Balachandran said. “The heat is produced
where it is needed.”
The new membrane reactor also performs an additional chemical trick: By constantly
removing hydrogen from the stream, the membrane alters the ratio of reactants
to products, enabling the reaction to make more ethylene than it theoretically
could have before reaching equilibrium. “We are essentially confusing or cheating
the thermodynamic limit,” Balachandran said. “The membrane reactor thinks: ‘Hey,
I haven't reached equilibrium yet, let me take this reaction forward.'”
While Balachandran's team, which included chemists Stephen Dorris, Tae Lee,
Chris Marshall and Charles Scouton, designed this experiment merely to prove
the membrane's capability to produce ethylene, he hopes to extend the project
by pairing with an industrial partner who would produce the membranes commercially.
Since the membrane reduces the number of steps required to produce ethylene,
the technology could enable the chemical to be produced more cheaply, he said.
The results of the research are expected to be presented at the 2008 Clean
Technology conference in Boston in June.
Argonne National Laboratory seeks solutions to pressing national problems in science and technology.
The nation's first national laboratory, Argonne conducts leading-edge basic
and applied scientific research in virtually every scientific discipline. Argonne
researchers work closely with researchers from hundreds of companies, universities,
and federal, state and municipal agencies to help them solve their specific
problems, advance America 's scientific leadership and prepare the nation for
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the U.S.
Department of Energy's Office
of Science.
For more information, please
contact Steve McGregor (630/252-5580 or media@anl.gov)
at Argonne.
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