Researchers at the University of Texas at Arlington have uncovered an efficient, one-step process for the conversion of carbon dioxide and water into usable fuel. According to the team, exposure to high pressures, temperatures and concentrated light can turn a mixture of carbon dioxide and water directly into liquid hydrocarbon fuel; a feat that could eventually prove beneficial for the environment.
As the scientists point out, this incredibly simple and inexpensive technology could be used to remove excess carbon dioxide from the atmosphere, thus putting a stop to global warming. In addition to producing usable fuel, the reaction generates oxygen as a byproduct. Speaking about the research, recently published in the journal Proceedings of the National Academy of Sciences, Frederick MacDonnell, the head of UTA’s chemistry and biochemistry departments and the study’s leader, said:
Our process also has an important advantage over battery or gaseous-hydrogen powered vehicle technologies as many of the hydrocarbon products from our reaction are exactly what we use in cars, trucks and planes, so there would be no need to change the current fuel distribution system.
Titled “Solar photothermochemical alkane reverse combustion”, the research outlines an innovative one-step process, by which CO2 and water can be transformed into liquid hydrocarbons and oxygen. The reaction, according the scientists, takes place in a special photothermochemical flow reactor, at temperatures of around 180 to 200 degrees Celsius and pressures of nearly 6 atmospheres. Brian Dennis, a professor of aerospace and mechanical engineering at the university, said:
We are the first to use both light and heat to synthesize liquid hydrocarbons in a single stage reactor from carbon dioxide and water. Concentrated light drives the photochemical reaction, which generates high-energy intermediates and heat to drive thermochemical carbon-chain-forming reactions, thus producing hydrocarbons in a single-step process.
For the reaction, the researchers used a hybrid photochemical and thermochemical catalyst containing titanium dioxide. Because of its inability to absorb the entire visible light spectrum, however, the team is currently looking for a better photo-catalyst that could pave the way for eco-friendly solar liquid fuels. To achieve that, the scientists would have to use specially-designed parabolic mirrors to focus sun’s rays on the catalyst bed. Doing so would in turn provide both heat and light needed for the process.
According to the team, the system could also be programmed to use the excess heat from the sun for other functions, including water purification and product separations The research is supported by grants from the Robert A. Welch Foundation and the National Science Foundation.
Source: University of Texas at Arlington