KIER Develops New Catalyst to Convert Carbon Dioxide into "Eco-Friendly Fuel"

A new catalyst that converts carbon dioxide (CO2) into eco-friendly fuel has been developed in South Korea.

The Korea Institute of Energy Research announced on October 30 that Dr. Koo Kiyeong and his team from the Hydrogen Research Division have developed a world-class catalyst for the reverse water-gas shift reaction.

The reverse water-gas shift reaction is a technology that reacts carbon dioxide with hydrogen (H2) in a reactor to produce carbon monoxide (CO) and water (H2O).

Carbon monoxide generated in this process can be mixed with the remaining hydrogen to create synthesis gas, which can then be used as a raw material for synthetic fuels such as E-Fuel or methanol. For this reason, the reverse water-gas shift reaction is drawing attention as a key technology that could lead the future eco-friendly fuel industry.

E-Fuel refers to fuel produced using hydrogen generated from renewable energy and carbon dioxide captured from the air or derived from biomass. It is also emerging as a carbon-neutral fuel that can replace conventional fossil fuels.

Testing the performance of a newly developed catalyst using real-time infrared spectroscopy. Provided by Korea Institute of Energy Research

The reverse water-gas shift reaction achieves a high conversion rate of carbon dioxide at high temperatures above 800 degrees Celsius. For this reason, nickel-based catalysts, which have greater thermal stability than other metals, are mainly used.

However, nickel-based catalysts have the drawback that their particles tend to agglomerate when exposed to high temperatures for extended periods, reducing catalytic activity. In low-temperature environments, byproducts such as methane are generated, which lowers the productivity of carbon monoxide.

As a result, there is active research to develop catalysts that maintain high activity even at low temperatures, aiming to reduce process costs and improve efficiency.

In line with this research direction, the team developed a copper-based catalyst, which is relatively inexpensive and abundant, overcoming the limitations of existing catalysts. The newly developed copper-magnesium-iron mixed oxide catalyst demonstrated performance that was 1.7 times faster and produced 1.5 times more carbon monoxide than commercial copper catalysts under high-temperature (400 degrees Celsius) conditions.

In particular, unlike nickel catalysts, copper-based catalysts can selectively produce only carbon monoxide at temperatures below 400 degrees Celsius without generating byproducts such as methane.

However, the thermal stability of copper decreases at 400 degrees Celsius, which was identified as a limitation. To address this, the research team implemented a layered double hydroxide structure.

The layered double hydroxide structure is a sandwich-like form in which water and anions are intercalated between thin metal layers, allowing various physical and chemical properties to be achieved by adjusting the types and ratios of metal ions. Drawing on this principle, the team mixed iron and magnesium to fill the spaces between copper particles, preventing agglomeration and thereby enhancing thermal stability.

The catalyst developed by the team demonstrated a carbon monoxide production rate more than 1.7 times faster and a yield more than 1.5 times higher than commercial copper catalysts. Notably, this catalyst also showed a carbon monoxide production rate 2.2 times faster and a yield 1.8 times higher than precious metal catalysts such as platinum, which are known for their high activity at low temperatures.

Dr. Koo stated, "Low-temperature CO2 hydrogenation catalyst technology is an innovative achievement that enables the efficient production of carbon monoxide using inexpensive and abundant metals, and it can be directly applied to the production of key raw materials for sustainable synthetic fuels. Our team will continue research so that this newly developed catalyst technology can be applied in real industrial settings, contributing to the realization of carbon neutrality and the commercialization of sustainable synthetic fuel production technologies."

This content was produced with the assistance of AI translation services.