Princeton University start-up aims to turn carbon dioxide into fuels

Liquid Light is a New Jersey start-up that turns carbon dioxide into fuels and industrial chemicals. That sounds like a winning formula in today’s economy where venture capitalists are investing millions of dollars in green technologies to combat climate change. But back in the early 1990s when the research was launched, “nobody cared about carbon dioxide, said Andrew Bocarsly, professor of chemistry at Princeton University.

Today, scientists around the globe are searching for ways to store, dispose of, or prevent the formation of the greenhouse gas, which is a major driver of global climate change. Liquid Light hopes to take this concept one step further and harness waste CO2 as a source of carbon to make industrial chemicals and fuels. The company’s core technology involves taking carbon dioxide and mixing it in a water-filled chamber with an electrode and a catalyst to convert carbon dioxide into methanol.

The technology behind the process is simple: Take CO2 and mix it in a water-filled chamber with an electrode and a catalyst. The ensuing chemical reaction converts CO2 into a new molecule, methanol, which can be used as a fuel, an industrial solvent or a starting material for the manufacture of other chemicals.

Liquid Light's founders include Bocarsly and his former graduate student Emily Cole, who earned her Ph.D from Princeton in 2009. Cole helped revive efforts in Bocarsly's lab to study the conversion of CO2 into usable fuels, which led to the launch of Liquid Light.

Zero interest in research

Back in the 1990s, a former Ph.D student of Bocarsly's named Chao Lin conducted some of the earliest experiments on turning CO2 into methanol. As Bocarsly recalled, Lin was quite excited about his success. However, said Bocarsly, "We published that finding in 1994 and there was approximately zero interest in it."

The work languished until 2005 when Cole, then a new graduate student, told Bocarsly she wanted to work on a clean-energy project. She took up the challenge of reproducing Lin's results, but this time using sunlight instead of electricity to drive the reaction.

Bocarsly likes to call the process "reverse combustion" because it is like running a burning reaction backwards. Instead of burning fuel and oxygen to produce CO2, the CO2 converts back into fuel and oxygen. This time, when the team published in May 2008 in the Journal of the American Chemical Society, the results generated a lot of interest.

Liquid Light licensed its technology from Princeton. Cole leads a team of chemists who tackle the practical issue of how to scale up a laboratory invention to an industrial scale, while Bocarsly chairs the company's scientific advisory board.

Taking the idea to market

One person who read that paper was Kyle Teamey, an entrepreneur who was representing a venture capital firm that wanted to invest in clean-energy technologies. He was attracted to the idea that waste CO2 could be put to use as a starting material for making fuels and industrial chemicals that could be sold at a profit. "Everyone had been talking about burying CO2 underground," said Teamey. "Why not instead turn carbon dioxide into something valuable?"

After months of talks with Bocarsly and Cole as well as other advisers, Teamey and Cole co-founded Liquid Light. The company licensed the technology from Princeton University. Teamey serves as company president, while Cole and her team of chemists tackle the practical issue of how to scale up a laboratory invention to an industrial scale. Bocarsly serves as chair of the company's scientific advisory board.

The research has received funding from the Air Force Office of Scientific Research (AFSOR), the National Science Foundation and the Department of Energy (DOE). The collaboration between Liquid Light and the University was supported by the DOE Small Business Innovation Research program and the AFOSR Small Business Technology Transfer program.

Princeton's agreement with Liquid Light allowed the company to continue to collaborate with Bocarsly and his research team which lead to a surprising discovery: They managed to  turn CO2, which contains only one carbon, into a compound with a carbon-carbon bond, which vastly increases the possibilities for creating commercial applications. This was radical because although the reaction is certainly possible, it is highly unlikely to happen because so many other competing reactions are occurring.

"Everyone who electrochemically reduces CO2 today makes compounds with only one carbon," said Bocarsly. "Nobody makes things with carbon-carbon bonds." He paused. "But we can."

"That was a very 'wow' moment," recalled Cole, "because we thought that our process could only make methanol. But now we were finding that we could make a variety of products, and that is what makes this technology commercially interesting." She said Liquid Light scientists can now make more than 20 different products from CO2.

One of the chemicals Liquid Light can make is isopropanol, commonly known as rubbing alcohol and an important industrial chemical. Another is butanol, which could be commercially important as a fuel. Liquid Light's technology offers the potential to make these chemicals at lower cost than today's methods, which involve starting with fossil fuels such as petroleum and natural gas.


Back in the lab

While Liquid Light is developing the technology commercially, back in the chemistry department at Princeton, Bocarsly and his team are tackling a question that has puzzled the chemist since the 1990s: Why does pyridinium work so well as a catalyst for the reaction?

Bocarsly and his team — in collaboration with Steven Bernasek, professor of chemistry — are doing studies to understand the steps in the chemical reaction, and they are making rapid progress. "There are clearly some intermediate products formed during the reaction that do not sit around for a long time and are not there in very high concentrations," said Bocarsly.
 
The Princeton team also is studying the factors that determine which products can be made from CO2. They published  their findings in the journal ChemSusChem last year.
 
Meanwhile, scientists at Liquid Light are overcoming the practical hurdles inherent in converting laboratory findings to commercial technologies. One finding is that using sunlight to drive the reaction is not as efficient as using standard electricity from a wall outlet, so the researchers are exploring ways to harness electrical power generated from green technologies such as wind or hydroelectric power.

Citing government statistics that the United States generates about 5.5 billion metric tons of CO2 per year, Teamey said it will not be hard to obtain the starting materials for this new industry. However, the CO2 needs to be relatively pure, a requirement that rules out gasoline tailpipes and coal-fired power plants. Instead, said Teamey, the CO2 could come from manufacturing facilities, such as fertilizer manufacturers and cement plants, which according to Teamey emit some 100 million tons of high-purity CO2 each year.

Cole said her transition from Princeton Ph.D. graduate to startup employee has been a smooth one. "Startups can be very exciting because you are taking work from the academic setting and trying to make it work economically in the marketplace," she said. "It is rewarding because you can see your project from graduate school become an actual technology that impacts people."
 
This article is an edited version of a news article published on Princeton University’s news portal on 14 June 2012. The full version can be found at http://www.princeton.edu/main/news/archive/S33/95/96G16/index.xml?section=featured