Researchers at Stanford University in the US have discovered a new method to produce liquid ethanol from carbon monoxide gas, providing an eco-friendly alternative to conventional ethanol production.

The results of the research were published in the 9 April advanced online edition of the journal Nature.

Stanford chemistry assistant professor and Nature study coauthor Matthew Kanan said, "We have discovered the first metal catalyst that can produce appreciable amounts of ethanol from carbon monoxide at room temperature and pressure – a notoriously difficult electrochemical reaction."

At present, most ethanol is produced at high-temperature fermentation facilities that chemically convert corn, sugarcane and other plants into liquid fuel.

The new technique, which is developed by Kanan and Stanford graduate student Christina Li, requires no fermentation and could also help address many of the land- and water-use issues surrounding ethanol production today.

For the Nature study, the scientists built an electrochemical cell, a device comprising two electrodes placed in water saturated with carbon monoxide gas.

Once a voltage is applied across the electrodes of a conventional cell, current flows and water is converted to oxygen gas at one electrode and hydrogen gas at the other electrode.

During the experiment, the scientists found that a slightly altered oxide-derived copper catalyst produced propanol with 10% efficiency, and are working to improve the yield for propanol by further tuning the catalyst’s structure.

The research was supported by Stanford University, the National Science Foundation and the US Department of Energy.