Researchers at Ulsan National Institute of Science and Technology have developed a new way of converting carbon dioxide to a road-ready diesel fuel.
Their findings, described in a paper published in the journal Applied Catalysis B: Environmental, showed that changing the currently existing catalysts used in the conversion could turn carbon dioxide into liquid hydrocarbon-based fuel in one single step.
"We believe the new catalyst breaks through the limitation of CO2-based FT synthesis and will open the avenue for new opportunity for recycling CO2 into valuable fuels and chemicals," said Jae Sung Lee, Professor of Energy and Chemical Engineering at UNIST and lead author of the study, in a press release.
The new catalyst, a delafossite-based catalyst, is composed of inexpensive, earth-abundant copper and steel is used in a reaction between CO2 emissions of industrial plants and H2 generated from solar hydrogen plant to produce diesel.
At present, the most commonly used catalysts for the reactions of H2 with CO2 are low molecular weight substances, such as methane and methanol. However, the low value of these catalysts produces generally low reduction effects of carbon dioxide. However, compared to methane and methanol, diesel fuels have longer chain of carbon and hydrogen atoms.
Using the new delafossite-CuFeO2 as the catalyst precursor, the researchers were able to create longer carbon chains, allowing the production of diesel.
The researchers noted that their direct CO2-FT synthesis is different from Audi's CO2-to-dielsel conversion process. The Audi's conversion process involves two steps, including the reverse water gas shift (RWGS) reaction and CO Fisher-Tropsch (FT) synthesis, while the researchers' synthesis only involves a single step.
With their findings, the researchers hope that their new catalyst could help reduced the levels of carbon dioxide in the atmosphere and the diesel made during the synthesis could be used as alternative fuel to gasoline.