Fischer Tropsch Process Reveals Self-Sustained Oscillations

Oct. 6, 2023
Discovery could lead to enhanced fuel production efficiency.

Researchers at Washington State University have made a significant discovery regarding the Fischer Tropsch process, a catalytic reaction used to convert coal, natural gas or biomass into liquid fuels. According to an Oct. 5 press release on the university’s site, they found that this process exhibits self-sustained oscillations, unlike most catalytic reactions that maintain a steady state. These oscillations involve periodic shifts in activity levels from high to low and vice versa. The discovery, published in Science, suggests that these controlled oscillatory states could potentially enhance reaction rates and product yields, offering more efficient fuel production methods in the future.

“Usually, rate oscillations with large variations in temperature are unwanted in chemical industry because of safety concerns,” said corresponding author Norbert Kruse, Voiland Distinguished Professor in WSU’s Gene and Linda Voiland School of Chemical Engineering and Bioengineering, in the press release. “In the present case, oscillations are under control and mechanistically well understood. With such a basis of understanding, both experimentally and theoretically, the approach in research and development can be completely different – you really have a knowledge-based approach, and this will help us enormously.”

The researchers stumbled upon these oscillations accidentally when trying to stabilize reaction temperatures, eventually uncovering the underlying mechanisms. As temperature increases, reactant gases lose contact with the catalyst surface, slowing down the reaction. When the temperature decreases, the reaction speeds up as reactant gas concentration on the catalyst surface rises. This cycle repeats, creating oscillations.