New technology turns carbon dioxide into fuel

Haotian Wang is a biomolecular and chemical engineer at Rice University who has a team of scientists dedicated to the mission of transforming greenhouse gases into useful products for humanity. Recently, Wang and his group created a reactor capable of converting the CO2 from our atmosphere into pure liquid fuel.

In fact, what is produced is high purified amounts of the so-called formic acid. This substance is usually derived from carbon dioxide through very expensive purification and refinement processes that consume, in addition to the business and consumer dollar signs in the end product, a lot of energy. Wang's team reactor represents an evolution in this sense, because it produces the same substance directly and purely, eliminating the range of commonly used processes, and consuming less energy.

In laboratory tests, where the machine achieved 100 uninterrupted working hours, it was found that the invention achieved a 42% efficiency in energy conversion. This means that almost half of electrical energy can be stored in formic acid as a liquid fuel.

"Formic acid is an energy carrier, " Wang explains. "It is a fuel that can generate electricity and emit carbon dioxide - again recyclable." This substance is also of utmost importance in the chemical engineering industry, serving as the raw material for creating various materials.

What made everything possible

The reactor only came true because of two advances in science, as Chaun Xia, lead author of the scientific article on the invention, states. The first advance was the creation of a robust two-dimensional catalyst made of a special chemical element called bismuth. "Bismuth is a very heavy atom compared to transition metals like copper, iron or cobalt, " says Wang. "Its mobility is much lower, especially under reaction conditions, which stabilizes the catalyst."

The second advance, in turn, is the introduction of a solid electrolyte in the reaction that eliminates the need for salt. According to the researchers, the most common processes of transformation generate a final product full of salts. However, most applications require these salts to be removed, an extremely laborious and expensive procedure.

Expectations for the future

Not satisfied, researchers want to go further. They plan to adapt the reactor to produce more expensive and better known substances such as ethanol fuel, acetic acid and propanol. "Reducing carbon dioxide is very important because of its effect on global warming, " says Wang. "If electricity comes from renewable sources such as the sun or wind, we can create a loop that turns CO2 into something useful without polluting it anymore."