LEUVEN, Belgium – A collaboration between scientists at KU Leuven (University of Leuven), Belgium, and Stanford University has revealed the mechanism behind the direct conversion process of natural gas into methanol at room temperature. This discovery will have major consequences for the future use of methanol in various everyday applications. The findings were published in Nature.
Methanol is among the 20 most commonly used substances in the chemical industry. It’s used to produce antifreeze, fuels, solvents and various kinds of plastic. The substance is made from natural gas (methane). The large-scale conversion of methane into methanol currently involves various steps under high pressure and at a high temperature, making it a process that requires a lot of energy.
In the ‘90s, scientists developed a more direct method to produce methanol – a process that even produces extra energy. However, scientists didn’t really understand the process. It was a kind of “black box” in which they inserted methane, with a big chance that methanol would come out at the other end.
Twenty years later, postdoctoral researcher Pieter Vanelderen from the Centre for Surface Chemistry and Catalysis at KU Leuven, has unraveled the mechanism behind the process in collaboration with chemists from Stanford University.
The chemical reaction involves adding a catalyst that is a zeolite with added iron. Professor Bert Sels, from the KU Leuven Centre for Surface Chemistry and Catalysis, said, “We found that the iron needs to bind to the zeolite in a flat, bound orientation.”
“We have provided the first exact definition of what the iron atom looks like that is needed to convert methane into methanol at room temperature. Furthermore, we can describe why this conversion method is so successful,” explained Pieter Vanelderen, also from KU Leuven Centre for Surface Chemistry and Catalysis. This discovery may revolutionize the production of methanol and, by extension, all its derivatives that we use in our everyday lives.
“This breakthrough has happened because we were the first chemists to join forces with biochemists to work on this topic,” said Vanelderen. “Our colleagues at Stanford are specialized in the use of enzymes as catalysts in chemical reactions. Using methods initially developed to study iron-containing enzymes, they managed to take a ‘picture,’ as it were, of what it is that happens to this iron-containing zeolite during the conversion of methane into methanol. This information allowed us to determine which specific iron atom was doing the work and to find its exact location in the zeolite.”
Now that scientists know exactly what the catalyst looks like, they can start imitating and optimizing it in the lab. This opens up quite a few possibilities for the future. For one thing, the production of the methanol needed to produce plastic will become a lot cheaper. The catalyst is also useful for the conversion of nitrogen oxides. It could be used, for instance, to clean the exhaust fumes of cars.
The Research Foundation Flanders (FWO) and the U.S. National Science Foundation funded the research.