Carbon dioxide gets new life as it's recycled into gasoline

— -- Carbon dioxide, the chief greenhouse gas, is public enemy No. 1 to environmentalists. CO2 emissions from vehicle tailpipes have helped spawn a multibillion-dollar ethanol industry as the nation fights global warming and strives to import less foreign oil.

But at least a handful of companies and scientists are turning that battle on its head: They're finding ways to recycle CO2 and turn it back into gasoline and other transportation fuels.

While their projects are in the early stages, researchers say they've tested their technologies in the lab and are poised to unveil prototypes that could lead to commercial rollouts in as little as two years. If successful, such initiatives could reduce dependence on carbon-spewing, petroleum-based products, as well as renewable fuels such as corn ethanol that compete with food supplies.

"Having a homegrown alternative to (oil) is an attractive proposition," says Jim Miller, a scientist at Sandia National Laboratories who's working on a CO2-to-fuel project.

Scientists demonstrated years ago that CO2 can be converted into liquid fuel by breaking it apart and combining the carbon atom with hydrogen. Those are the basic building blocks of hydrocarbons, such as oil and coal, and feed stocks such as corn and sugar cane.

The problem: CO2 is very stable and can be split only under high temperature and pressure. That requires a lot of energy, which drives up costs. The start-ups are devising ways to unravel CO2 using less energy.

Turbocharging their efforts: oil prices that were skyrocketing until recently, and a push in Congress to require utilities, oil refiners and others to pay fees for each ton of CO2 they spew. Under legislation anticipated by next year, the industries would eventually have to curtail their emissions.

"There's just plentiful CO2, and someone's going to be willing to supply it to us," says Derek McLeish, CEO of Carbon Sciences, one of the start-ups.

Running ahead

Carbon Sciences is furthest along in the CO2-to-fuels quest. McLeish founded the company in 2006 as Zingerang, a mobile communications provider. But faced with a crowded wireless marketplace in 2007, he and other investors pivoted sharply from communications to carbon. They also changed the company's name, went public and raised $2.5 million.

In June, company chief technology officer Naveed Aslam figured out a way to break down CO2 at low temperature and pressure. His secret? Biocatalysts.

Although catalysts, such as enzymes and bacteria, can split CO2, they're very expensive, and typically must be replaced after every reaction. Aslam invented a polymer shell that protects them so they can be recycled. The same technology can extract hydrogen from water, avoiding the need for energy-intensive hydrolysis. The carbon and hydrogen are joined to form methanol, which can be refined into gasoline or jet fuel.

Aslam believes catalysts can be reused up to several million times but can't be certain until a prototype is completed this quarter. Costs should be competitive with ethanol, which now wholesales for about $1.65 a gallon, executives say.

Many companies are working to convert the hydrocarbons in algae and plant waste into biodiesel and cellulosic ethanol. But McLeish says, "Ours is the most direct path," and ultimately, quicker and cheaper.

Carbon Sciences likely would license its technology to oil refiners, which emit large amounts of CO2 and have the expertise and infrastructure to produce gasoline, McLeish says. Other prospects include coal plants and concrete makers, which are big CO2 producers and will likely have to install technology to capture it. Although CO2 culled from such sources ultimately would be emitted through tailpipes, it would displace new oil, substantially reducing carbon emissions. McLeish expects a commercial deployment by 2011.

David Doniger, policy director for the Natural Resources Defense Council, says such technology would be better for the environment than burning new fossil fuels. But he would prefer to capture CO2 from coal plants and store it underground — technology that's at least a decade away — and shift from gasoline-fueled cars to electric vehicles supplied by wind or solar energy.

Other CO2-to-fuel approaches:

•Sunlight. Sandia lab researchers are tapping the sun's power to minimize energy use. They've invented a reactor containing a ceramic ring made of iron oxide and cobalt. A solar concentrator heats the ceramic material to 2,700 degrees Fahrenheit, forcing it to give up its oxygen. The ring then rotates to a colder chamber containing carbon dioxide. Having released its oxygen, the ceramic borrows oxygen atoms from the CO2, leaving carbon monoxide only. The cycle repeats continuously.

The same process removes oxygen from water to produce hydrogen. The carbon monoxide and hydrogen are joined to make a synthetic gas, which can be turned into methanol or gasoline. A prototype is scheduled to be ready late this month.

•Wind. Morphic Technologies of Sweden has patented an enzyme to absorb CO2 from the air. Wind-turbine blades, coated with the enzyme, generate a huge air mass as they spin. CO2 sticks to the blades and is transported to the base of the turbine. There, excess energy from the wind turbines splits the CO2 and water into carbon and hydrogen. Since it's scraping CO2 from the air, Morphic could sell carbon credits to industries that must cut or offset emissions under expected greenhouse gas restraints, says CEO Martin Valfridsson.

Ahmed Ghoniem, an MIT professor of mechanical engineering, says CO2-to-fuels projects are technically feasible but face high hurdles. "Can you scale it up to produce a sufficient amount of (fuel) so you can build a business around it? It's challenging."