Engineers at a US university have developed a way to use copper nanotubes to reduce carbon monoxide waste into useful acetic acid
Spotted: Engineers at Rice University are working on a way to turn carbon monoxide into acetic acid, using a continuous catalytic reactor powered by renewable energy. The research teams, led by chemical and biomolecular engineers Haotian Wang and Thomas Senftle of Rice’s Brown School of Engineering, built on an earlier process for producing formic acid from carbon dioxide and an electro-catalyst.
Acetic acid is the chemical that gives vinegar its tartness, and is also used as an antiseptic; a solvent for ink, paint and coatings; and in the production of vinyl acetate, a precursor to PVA glue. The team first developed computational models that showed some types of edge on copper nano-cubes, such as a more corrugated surface, could aid in breaking carbon-oxygen bonds in the carbon monoxide and steer the products. They then used the copper nanotubes and a solid electrolyte as catalysts to reduce the carbon monoxide into acetic acid and alcohols.
In a continuous lab operation that took 150 hours, the reactor produced a solution that was up to 2 per cent acetic acid in water. Furthermore, the acid component was up to 98 per cent pure, an improvement on earlier attempts to catalyse CO into liquid fuel.
Explaining the process further, Wang said that “We’re upgrading the product from a one-carbon chemical, the formic acid, to two-carbon, which is more challenging. People traditionally produce acetic acid in liquid electrolytes, but they still have the issue of low performance as well as separating the product from the electrolyte.” Senftle added that, “Acetic acid is typically not synthesized, of course, from CO or CO2. That’s the key here: We’re taking waste gases we want to mitigate and turning them into a useful product.”
Written By: Lisa Magloff