Diatoms such as this may be used to create multiple products at one time, such as biofuels and electronic materials, in the process making this approach to producing fuel more cost-effective than ever before. Image: Oregon State University

Diatoms, tiny
marine life forms that have been around since the dinosaurs, could finally make
biofuel production from algae truly cost effective—because they can
simultaneously produce other valuable products such as semiconductors,
biomedical products and even health foods.

Engineers at
Oregon State University (OSU) concede that such technology is pushing the
envelope a bit. But it’s not science fiction—many of the needed advances have
already been made, and the National Science Foundation just provided a
four-year, $2 million grant to help make it a working reality.

In theory, and
possibly soon in practice, these amazing microscopic algae will be able to take
some of the cheapest, most abundant materials on Earth—like silicon and
nitrates—and add nothing much more than sunshine, almost any type of water, and
carbon dioxide to produce a steady stream of affordable products.

The concept is
called a “photosynthetic biorefinery.” Sand, fertilizer, a little sun, and
saltwater, in other words, might someday power the world’s automobiles and
provide materials for electronics, with the help of a tiny, single-celled
microstructure that already helps form the basis for much of the marine food
chain and cycles carbon dioxide from the Earth’s atmosphere.

“This NSF program
is intended to support long-range concepts for a sustainable future, but in
fact we’re demonstrating much of the science behind these technologies right
now,” says Greg Rorrer, an OSU professor and head of the School of Chemical,
Biological, and Environmental Engineering. Rorrer has studied the remarkable
power of diatoms for more than a decade.

“We have shown
how diatoms can be used to produce semiconductor materials, chitin fibers for
biomedical applications, or the lipids needed to make biofuels,” he says. “We
believe that we can produce all of these products in one facility at the same
time and move easily from one product to the other.”

Biofuels can be
made from algae, scientists have shown, but the fuels are a comparatively
low-value product and existing technologies have so far been held back by cost.
If this program can help produce products with much higher value at the same
time—like glucosamine, a food product commonly sold as a health food supplement—then
the entire process could make more economic sense.

Much of the cost
in this approach, in fact, is not the raw materials involved but the facilities
needed for production. As part of the work at OSU, researchers plan to develop
mathematical models so that various options can be tested and computers used to
perfect the technology before actually building it.

The key to all of
this is the diatom itself, a natural nanotechnology factory that has been found
in the fossil record for more than 100 million years. Diatoms evolved sometime
around the Jurassic Period when dinosaurs flourished. A major component of
phytoplankton, diatoms have rigid microscopic shell walls made out of silica,
and the capability to biosynthesize various compounds of commercial value.

“Regular algae
don’t make everything that diatoms can make,” Rorrer says. “This is the only
organism we know of that can create organized structures at the nanolevel and
naturally produce such high-value products. With the right components, they
will make what you want them to make.”

Source: Oregon State University