One-Pot Fischer-Tropsch Produces Aldehydes and Alcohols

In another development related to the Fischer-Tropsch process, chemical engineers at Washington State Univ. have developed a catalyst to produce alcohols and aldehydes in a one-step, one-pot process.

Aldehydes and alcohols are currently manufactured via hydroformylation. In this reaction, carbon monoxide and hydrogen react in the presence of a target olefin and a rhodium-metal homogeneous catalyst to produce aldehydes. A large portion of the aldehydes is then hydrogenated to alcohols. This process requires several steps, as well as an expensive catalyst that, because it is in the same liquid phase as the products, requires an extra step to separate it from the product stream.

Developed by Norbert Kruse, the Voiland Distinguished Professor of chemical engineering and bioengineering, and Yizhi Xiang, a postdoctoral research associate working with him, the new catalyst is an alkali-promoted cobalt-manganese (CoMn) compound that is much cheaper than rhodium. It is a solid, so it does not require an extra processing step to separate it from the product stream. By changing the hydrogen-to-carbon-monoxide partial pressure ratio from low to high (at a constant total pressure), the engineers were able to tune the product spectrum — from mostly...