American Chemical Society, Licht presented a method for using an electrochemical process to harvest carbon dioxide from the ambient atmosphere and convert it to carbon nanofibers for creating carbon composites used in lightweight, high-performance products.

PFor decades now, scientists have been sounding the alarm about increasing levels of carbon dioxide in the atmosphere and the role it plays in climate change, but the world has been largely unsuccessful at reducing the amount of CO2 floating around above our heads. Stuart Licht of George Washington University wants to convert a large portion of the greenhouse gas into a raw material to make things like aircraft, race cars, sports equipment and even wind turbines.

On Wednesday at a meeting of the American Chemical Society, Licht presented a method for using an electrochemical process to harvest carbon dioxide from the ambient atmosphere and convert it to carbon nanofibers for creating carbon composites used in lightweight, high-performance products.

The basic concept requires melting lithium carbonate with lithium oxide dissolved in it and then adding air from the atmosphere and direct electrical current via nickel and steel electrodes. The CO2 in the air dissolves and is broken down, with the whole reaction creating more lithium oxide to further fuel the process, oxygen and carbon nanofibers that build up on the steel electrode where they can be removed, according to Licht.

The reaction is powered by heat and electricity gathered through an efficient hybrid solar energy system with a photovoltaic cell to generate the electricity mated with a thermal energy collector to heat up the electrolytic cell in which the reaction takes place.

Licht says that in addition to essentially sequestering CO2 away from the atmosphere, the process is also a highly economical way of creating a valuable raw material. He estimates the energy input costs to be only about $1,000 per ton of carbon nanofiber, which is worth as much as $25,000.

"Carbon nanofiber growth can occur at less than 1 volt at 750 degrees C, which for example is much less than the 3-5 volts used in the 1,000 degree C industrial formation of aluminum," he says.

But perhaps the most striking figure Licht cites is his claim that covering just 10 percent of the Sahara desert with the solar collectors used to power the reaction would be sufficent to reduce the amount of CO2 in the atmosphere to pre-industrial levels after only ten years of operation, even if we continue to release more CO2 at high levels. That could effectively erase a significant portion of modern society's contribution to climate change. Licht also says that so far in the lab, his team has been able to scale up the reaction an order of magnitude without any loss of efficiency.

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