Chocolate generates electrical power
Microbiologist Lynne Mackaskie and her
colleagues at the University of Birmingham in the UK have powered a fuel cell by
feeding sugar-loving bacteria chocolate-factory waste.
Chocolate
generates electrical power
• 01 June 2006
• NewScientist.com news
service
Willy Wonka could have powered his
Great Glass Elevator on hydrogen produced from his chocolate
factory.
Microbiologist Lynne Mackaskie and her
colleagues at the University of Birmingham in the UK have powered a fuel cell by
feeding sugar-loving bacteria chocolate-factory waste. "We wanted to see if we
tipped chocolate into one end, could we get electricity out at the other?" she
says.
The team fed
Escherichia
coli bacteria diluted caramel
and nougat waste. The bacteria consumed the sugar and produced hydrogen, which
they make with the enzyme hydrogenase, and organic acids. The researchers then
used this hydrogen to power a fuel cell, which generated enough electricity to
drive a small fan
(Biochemical Society
Transactions, vol 33, p
76).
The process could provide a use for
chocolate waste that would otherwise end up in a landfill. What's more, the
bacteria's job doesn't have to end once they have finished chomping on the sweet
stuff. Mackaskie's team next put the bugs to work on a production line that
recovers precious metal from the catalytic converters of old cars.
Place the bacteria in a vat with
hydrogen and liquid waste from spent converters, and the enzymes again get to
work. The same hydrogenase used to produce hydrogen splits the gas into its
constituents, generating electrons that react with palladium ions in the
solution. This forces the palladium out of the solution, and it sticks to the
bacteria. The palladium-coated bacteria can then be recycled as catalysts for
other projects, Mackaskie
says.
From issue 2554 of New
Scientist magazine, 01 June 2006, page 25
Posted: Per - Temmuz 13, 2006 at 11:07 PM
