Ohio State chemical engineers create fossil fuel technology that consumes carbon dioxide

Ris Twigg
Fri, 12 Jan 2018 03:23:32 +0000
Campus, Online Exclusive, Web, carbon dioxide, carbon emissions, chemical looping, CO2, environmental science, featured, fossil fuels, greenhouse gas emissions, methane, ohio state, Ohio State environmental research, osu, science, sustainability, sustainable energy

Liang-Shih Fan, distinguished university professor in chemical and biomolecular engineering, developed a fossil fuel technology that doesn’t emit greenhouse gases and cause pollution. Credit: Courtesy of Ohio State

Picture a world where burning fossil fuels would not mean emitting greenhouse gases like carbon dioxide into the air, creating pollution. With new technology produced by Ohio State chemical engineers, this hypothetical scenario could become reality.

Through a complicated process known as chemical looping, researchers, graduate and undergraduate students have developed a way to use shale, biomass and coal without the accompanying release of carbon dioxide into the atmosphere.

“You are able to actually reduce the methane usage by about 25 percent if you use co-feeding of the carbon dioxide and the steam into the chemical looping system,” said Liang-Shih Fan, distinguished university professor in chemical and biomolecular engineering. “And that gives you economic benefits.”

Fan said when carbon dioxide is released, it’s in its purest form, meaning that scrubbing the chemical compound — a process that “scrubs” carbon off power plants for burial in the ground after fossil fuels have combusted — is no longer necessary and the components remaining after the looping can be used for making other products.

The technology is meant to make the burning of fossil fuels a cleaner, efficient and sustainable process, said Fan and Peter Sandvik, a researcher and first-year graduate student in chemical engineering. The process has the ability to reduce coal consumption by 25 percent.

“A lot of people recognize that solar and renewable energy are the future,” Sandvik said. “Until then, chemical looping can kind of be a technology that covers the gap for what we have right now, which is pretty unsustainable.”

The chemical looping process eliminates the need for a variety of separation mechanisms, which can be quite expensive and inefficient, Sandvik said.

The entire process can be boiled down to a basic concept many Ohio State students learn in Chemistry 1210 — oxidation-reduction reactions.

Oxidation-reactions occur when an atom loses an electron and reduction reactions occur when an atom gains an electron.

In the case of chemical looping, oxygen is provided by metal oxide — rather than the oxygen in air directly — and combines with fossil fuels that are added to the system, according to Fan’s research.

Additionally, Fan and his team discovered a way to increase the lifespan of the metal oxide from 100 cycles to more than 3,000 cycles, extending plant operation from eight days to eight months. This means it takes less metal oxide particles to consume more carbon dioxide.

Another application of the technology essentially transforms methane, hydrogen and carbon monoxide into a product that researchers call “syngas” or synthesis gas.

“This particular reactant system is configured … so that carbon dioxide is coming out as syngas,” Fan said.

The syngas is able to form the base of a variety of other products, such as plastic and carbon fibers.

“It’s very advanced technology and very cost efficient,” he said.

When the individual technologies are combined, commercialization is brought closer to reality, Fan and Sandvik said.

The chemical looping process eliminates the need for a variety of separation mechanisms, which can be quite expensive and inefficient, Sandvik said.