This is a huge game changer. For forty years, the hydrogen economy
was a bad joke because there was no good way to produce hydrogen.
This changes all that. Even better it will clearly be applicable at
source were the biomass is produced.
The end products will be high quality hydrogen and the remaining
biomass with the sugars still intact but broken down. It may well
have improved commercial value.
It is too soon to tell, but this sounds perfect for agriculture. An
internal source of energy is produced and the first step in biomass
management consists of shredding and using a warmed digestor along
with the appropriate enzymes. The produced bio waste might even be
simply used as a green manure.
Breakthrough in
hydrogen fuel production could revolutionize alternative energy
market
BLACKSBURG, Va., April 4, 2013 – A team of Virginia Tech
researchers has discovered a way to extract large quantities of
hydrogen from any plant, a breakthrough that has the potential to
bring a low-cost, environmentally friendly fuel source to the world.
“Our new process
could help end our dependence on fossil fuels,” said Y.H. Percival
Zhang, an associate professor of biological systems
engineering in the College of Agriculture and Life
Sciences and the College of Engineering. “Hydrogen is one
of the most important biofuels of the future.”
Zhang and his team
have succeeded in using xylose, the most abundant simple plant
sugar, to produce a large quantity of hydrogen that previously
was attainable only in theory. Zhang’s method can be performed
using any source of biomass.
The discovery is a
featured editor’s choice in an online version of the chemistry
journal Angewandte Chemie, International Edition.
This new
environmentally friendly method of producing hydrogen utilizes
renewable natural resources, releases almost no greenhouse gasses,
and does not require costly or heavy metals. Previous methods
to produce hydrogen are expensive and create greenhouse gases.
The U.S. Department of
Energy says that hydrogen fuel has the potential to dramatically
reduce reliance of fossil fuels and automobile manufactures are
aggressively trying to develop vehicles that run on hydrogen fuel
cells. Unlike gas-powered engines that spew out pollutants, the only
byproduct of hydrogen fuel is water. Zhang’s discovery opens the
door to an inexpensive, renewable source of hydrogen.
Jonathan R. Mielenz,
group leader of the bioscience and technology biosciences division at
the Oak Ridge National Laboratory, who is familiar with Zhang’s
work but not affiliated with this project, said this discovery has
the potential to have a major impact on alternative energy
production.
“The key to this
exciting development is that Zhang is using the second most prevalent
sugar in plants to produce this hydrogen,” he said. “This amounts
to a significant additional benefit to hydrogen production and it
reduces the overall cost of producing hydrogen from biomass.”
Mielenz said Zhang’s
process could find its way to the marketplace as quickly as three
years if the technology is available. Zhang said when it does become
commercially available, it has the possibility of making an enormous
impact.
“The potential for
profit and environmental benefits are why so many automobile, oil,
and energy companies are working on hydrogen fuel cell vehicles as
the transportation of the future,” Zhang said. “Many people
believe we will enter the hydrogen economy soon, with a market
capacity of at least $1 trillion in the United States alone.”
Obstacles to
commercial production of hydrogen gas from biomass previously
included the high cost of the processes used and the relatively low
quantity of the end product.
But Zhang says he
thinks he has found the answers to those problems.
For seven years,
Zhang’s team has been focused on finding non-traditional ways to
produce high-yield hydrogen at low cost, specifically researching
enzyme combinations, discovering novel enzymes, and engineering
enzymes with desirable properties.
The team liberates
the high-purity hydrogen under mild reaction conditions at 122 degree
Fahrenheit and normal atmospheric pressure. The biocatalysts used
to release the hydrogen are a group of enzymes artificially isolated
from different microorganisms that thrive at extreme temperatures,
some of which could grow at around the boiling point of water.
The researchers chose
to use xylose, which comprises as much as 30 percent of plant cell
walls. Despite its abundance, the use of xylose for releasing
hydrogen has been limited. The natural or engineered microorganisms
that most scientists use in their experiments cannot produce hydrogen
in high yield because these microorganisms grow and reproduce instead
of splitting water molecules to yield pure hydrogen.
To liberate the
hydrogen, Virginia Tech scientists separated a number of enzymes from
their native microorganisms to create a customized enzyme cocktail
that does not occur in nature. The enzymes, when combined with
xylose and a polyphosphate, liberate the unprecedentedly high volume
of hydrogen from xylose, resulting in the production of about three
times as much hydrogen as other hydrogen-producing microorganisms.
The energy stored
in xylose splits water molecules, yielding high-purity hydrogen that
can be directly utilized by proton-exchange membrane fuel cells. Even
more appealing, this reaction occurs at low temperatures, generating
hydrogen energy that is greater than the chemical energy stored in
xylose and the polyphosphate. This results in an energy efficiency of
more than 100 percent — a net energy gain. That means that
low-temperature waste heat can be used to produce high-quality
chemical energy hydrogen for the first time. Other processes that
convert sugar into biofuels such as ethanol and butanol always have
energy efficiencies of less than 100 percent, resulting in an energy
penalty.
In his previous
research, Zhang used enzymes to produce hydrogen from starch, but the
reaction required a food source that made the process too costly for
mass production.
The commercial market
for hydrogen gas is now around $100 billion for hydrogen produced
from natural gas, which is expensive to manufacture and generates a
large amount of the greenhouse gas carbon dioxide. Industry most
often uses hydrogen to manufacture ammonia for fertilizers and to
refine petrochemicals, but an inexpensive, plentiful green hydrogen
source can rapidly change that market.
“It really doesn’t
make sense to use non-renewable natural resources to produce
hydrogen,” Zhang said. “We think this discovery is a game-changer
in the world of alternative energy.”
Support for the
current research comes from the Department of Biological Systems
Engineering at Virginia Tech. Additional resources were contributed
by the Shell GameChanger Program, the Virginia Tech College of
Agriculture and Life Sciences’ Biodesign and Bioprocessing Research
Center, and the U.S. Department of Energy BioEnergy Science Center,
along with the Division of Chemical Sciences, Geosciences and
Biosciences, Office of Basic Energy Sciences of the Department of
Energy. The lead author of the article, Julia S. Martin Del
Campo, who works in Zhang’s lab, received her Ph.D. grant from the
Mexican Council of Science and Technology.
Nationally ranked
among the top research institutions of its kind, Virginia
Tech’s College of Agriculture and Life Sciences focuses
on the science and business of living systems through learning,
discovery, and engagement. The college’s comprehensive curriculum
gives more than 3,100 students in a dozen academic departments a
balanced education that ranges from food and fiber production to
economics to human health. Students learn from the world’s leading
agricultural scientists, who bring the latest science and technology
into the classroom.
1 comment:
Since WHEN is water vapor NOT a 'greenhouse gas' ??!??
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