Seoul: Scientists have developed a new way turn carbon dioxide into diesel fuel for existing vehicles, a breakthrough that may revolutionise the automobile industry and bring us a step closer to eliminating greenhouse gas.
The benefits are two-fold, researchers said. The process removes harmful CO2 from the atmosphere and the diesel can be used as an alternative fuel to gasoline.
Researchers showed direct CO2 conversion to liquid transportation fuels by reacting with renewable hydrogen (H2) generated by solar water splitting.
The currently existing catalysts, used for the reactions of H2 with CO2 are limited mostly to low molecular weight substances, such as methane or methanol.
Besides, due to the low value of these catalysts, the reduction effects of CO2 is generally low.
However, the new delafossite-based catalyst converts CO2 into liquid hydrocarbon-based fuels (eg diesel fuel) in one single step.
These fuel samples can be used by existing diesel vehicles, like trucks and buses.
This new delafossite-based catalyst, 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.
“Diesel fuels have longer chain of carbon and hydrogen atoms, compared to methanol and methane,” said Yo Han Choi, from the Ulsan National Institute of Science and Technology (UNIST) in South Korea.
“Using delafossite-CuFeO2 as the catalyst precursor, we can create longer carbon chains and this would allow for the production of diesel,” said Choi.
This direct CO2-FT synthesis is different from the German car maker Audi’s CO2-to-dielsel conversion process, which actually involves two steps – reverse water gas shift (RWGS) reaction to CO followed by CO Fisher-Tropsch (FT) synthesis.
Proposed carbon capture and utilisation (CCU) system based on catalytic CO2 conversion to liquid hydrocarbon fuels with hydrogen supplied from solar water splitting.
“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 at UNIST.
The study was published in the journal Applied Catalysis B: Environmental.