Production of liquid ethanol from carbon monoxide (CO)

Ethanol or alcohol is considered a more environmentally friendly alternative fuel than fossil fuels except for its limitations. The common method of producing ethanol is fermenting sugar or cereals with alcoholic yeast. However, crops like corn (corn) often take time to harvest, occupy a lot of cultivation area and need a lot of water and fertilizer. Today, Stanford scientists have devised a way to produce liquid ethanol from carbon monoxide (CO).

This technology was developed by chemistry professor Matthew Kanan and graduate student Christana Li. While ethanol is extracted from fermentation, their technique uses saturated water with CO gas and places this solution in an electrochemical battery at room temperature.

Like other fuel cells, the CO-water battery has two positive and negative electrodes to rotate the current. In the case of hydrogen fuel cells, electric current can convert the battery-containing water into oxygen and hydrogen gas. By using cathode made from a copper oxide, Kanan and Li were able to reduce CO in water to ethanol and acetate.

With conventional copper cathodes, conversion efficiency is only about 1/10. Kanan explained: "Common copper electrodes contain stacked nanoparticles. The opposite copper oxide is made up of copper nanocrystals and all of them are joined together in a seamless grid with the boundaries are clearly defined ". This structure allows copper to use up to 57% of the current to produce ethanol and acetate according to Stanford and this is an impressive number.

However, it would be even better if the current used in the process could be derived from renewable energy sources and if CO could be derived from a greener source than fossil fuels. This is also what researchers are aiming at along with increasing process efficiency. They are also looking for ways to use technology to produce fuels other than ethanol.