Researchers target eucalyptus as source of fuel for biomass production

May 07, 2014 by Kimberly Moore Wilmoth

(Phys.org) —University of Florida Institute of Food and Agricultural Sciences researchers working to produce ethanol from plant material are taking a hard look at eucalyptus as a possible source for the clean fuel.

Joe Sagues, director of operations at the UF's Stan Mayfield Biorefinery Pilot Plant in Perry, Florida, and Ismael Uriel Nieves, project director at the plant, recently switched the focus of their lab-scale research from sugarcane and sorghum to for this study. They say the tree, most commonly associated with Australia and food for koalas, is a fast-growing hardwood that is easier to store and transport.

In their study, published online by the journal Applied Energy in April, they found that some eucalyptus had an increased sugar content, making it viable as a sustainable feedstock for .

In addition, during pretreatment, they switched from the more corrosive sulfuric acid to phosphoric acid to increase sugar yields.  Sulfuric acid requires special metal alloy containers, while phosphoric acid can be housed in commercial steel, which cuts down on initial capital costs in building a biofuel plant. The phosphoric acid also doesn't break down the released sugars as much, which increases overall yield.

The process involves injecting eucalyptus with phosphoric acid while under high temperature and pressure from steam, then rapidly releasing the pressure—a process known as a steam-explosion. After this step, enzymes are added to the mix to improve the release of sugars. After it cools, air, chemicals and trace minerals are added, and the slurry ferments.

At the end of the process, the mixture becomes fuel.

"The Stan Mayfield Biorefinery Plant in Perry allows our team to develop and succeed in experiments at the lab scale, and then prove the same methods on a much grander industrial demonstration scale," Sagues said. "It essentially acts as a bridge from the lab to commercial production."

Nieves explained that the phosphoric acid creates a phosphate byproduct.

"The remaining liquid could be used as fertilizer," Nieves said, "which would help recover some of the cost of chemicals."

They both say their research is all part of UF/IFAS' work to improve biofuel production in a way that makes economic sense.

The $20 million Stan Mayfield Biorefinery Plant opened in 2012 and is a cooperative research venture between UF/IFAS and Buckeye Technologies Inc. It is expected to be fully operational later this summer, producing up to 400 gallons of fuel ethanol and 5,000 pounds of organic acids for bioplastics each day.

Researchers with the University of Florida are developing economical and environmentally friendly ways to produce cellulosic ethanol – a clean-burning fuel produced from inedible that could end up replacing much of the country's gasoline.

Explore further: How to get high-quality RNA from chemically complex plants

Related Stories

Cheaper second-generation biofuel for cars

Feb 24, 2014

Producing second-generation biofuel from dead plant tissue is environmetally friendly - but it is also expensive because the process as used today needs expensive enzymes, and large companies dominate this market. Now a Danish/Iraqi ...

Recommended for you

How to get high-quality RNA from chemically complex plants

1 hour ago

Ask any molecular plant biologist about RNA extractions and you might just open up the floodgates to the woes of troubleshooting. RNA extraction is a notoriously tricky and sensitive lab procedure. New protocols out of the ...

Plant fertility—how hormones get around

2 hours ago

Researchers at Tokyo Institute of Technology have identified a transporter protein at the heart of a number of plant processes associated with fertility and possibly aging.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.