New process to create clean fuel from thin air!

For the first time, scientists, including one of Indian-origin, have directly converted carbon dioxide from the air into methanol at lower temperatures, an advance that may help create a sustainable fuel source from greenhouse gases.

The research is part of a broader effort to stabilise the amount of carbon dioxide (CO2) in the atmosphere by using renewable energy to transform the greenhouse gas into its combustible cousin - attacking global warming from two angles simultaneously.
Methanol is a clean-burning fuel for internal combustion engines, a fuel for fuel cells and a raw material used to produce many petrochemical products.

"We need to learn to manage carbon. That is the future," said GK Surya Prakash, director of the University of Southern California (USC) Loker Hydrocarbon Research Institute, who led the study along with George Olah of USC.

The researchers bubbled air through an aqueous solution of pentaethylenehexamine (or PEHA), adding a catalyst to encourage hydrogen to latch onto the CO2 under pressure.
They then heated the solution, converting 79 per cent of the CO2 into methanol. Though mixed with water, the resulting methanol can be easily distilled, Prakash said. Researchers hope to refine the process to the point that it could be scaled up for industrial use.

Despite its outsized impact on the environment, the actual concentration of CO2 in the atmosphere is relatively small - roughly 400 parts per million, or 0.04 per cent of the total volume, according to the National Oceanographic and Atmospheric Administration.

For a comparison, there is more than 23 times as much the noble gas Argon in the atmosphere - which still makes up less than 1 per cent of the total volume.

Previous efforts have required a slower multistage process with the use of high temperatures and high concentrations of CO2, meaning that renewable energy sources would not be able to efficiently power the process, researchers said.

The new system operates at around 125 to 165 degrees Celsius minimising the decomposition of the catalyst - which occurs at 155 degrees Celsius.

It also uses a homogeneous catalyst, making it a quicker "one-pot" process. In a lab, the researchers demonstrated that they were able to run the process five times with only minimal loss of the effectiveness of the catalyst.

The study was published in the Journal of the American Chemical Society.