A simple plant sugar can be turned into a potentially useful biofuel,
according to scientists.
Researchers in the US have developed a way of converting fructose, the
sugar that gives apples and oranges their sweet taste, into a fuel that
can be burned to generate energy.
The catalytic process creates 2,5-dimethylfuran (DMF), a liquid fuel
which stores 40% more energy than ethanol.
Scientists hope the new fuel will contribute to renewable replacements
for fossil fuels in the future, thereby helping to reduce global warming.
Currently ethanol, a type of alcohol, is the only biofuel produced on a
large scale. However, it suffers from several limitations. It has a
relatively low energy density - in other words, the amount of energy it
stores in a given volume is low - evaporates easily and can be
contaminated with water from the atmosphere.
The new fuel, DMF, has a higher energy content, does not absorb water,
and is less volatile making storage easier and safer.
Scientists led by Professor James Dumesic, at the University of
Wisconsin-Madison, developed a two-stage process for converting fructose
to DMF in a bio-reactor.
First the fructose is changed into an intermediate chemical,
hydroxymethylfurfural (HMF) in water using a low-boiling point solvent
and acid catalyst.
The HMF is extracted and converted to DMF with a copper-based catalyst.
The conversion removes two oxygen atoms from the compound, which has the
effect of making it a transportable liquid instead of a gas. Details of
the process were outlined on Wednesday in the journal Nature.
Prof Dumesic said more research was needed before the technology can be
commercialised - for example, tests of the environmental health impact
of DMF. He said: "There are some challenges that we need to address, but
this work shows that we can produce a liquid transportation fuel from
biomass that has energy density comparable to petrol."
Check for earlier Pacific Biofuel posts: http://pacbiofuel.blogspot.com/