Interesting chemistry, it's kind of like a modified Fischer-Tropsh but at room temperature and pressure (and not a complete reduction to hydrocarbon level)::
> "To achieve maximum selectivity and production of acetate from a direct CO2 feed, a two-step electrolyser system was demonstrated to convert CO2 to CO and then CO to acetate through a tandem process ... [stage one] produces a gaseous product stream containing CO, H2 and trace CO2... The gas product stream was then fed to the cathode chamber of the CO electrolyser... By maximizing the conversion of the first and second electrolysers, as well as specifically targeting acetate over other multi-carbon products, this system was able to achieve a single-pass conversion of CO2 to acetate of 25%..."
That's a respectable yield, but it doesn't look too easy to scale up. That's typical for research prototype work like this (iridium anode seems tricky). They're also using 100% CO2 as the feed gas so there's a preconcentration step from atmospheric CO2 required (400ppm starting -> 100% pure takes some energy input).
Seems fairly promising, they were getting 0.19 g of yeast (marmite basically, or nutritional yeast) per g of produced acetate. Mars colonists take note.
If it becomes a problem just getting enough iridium for scale, there's lots of iridium in asteroids. Could be worthwhile if you're a space colony, or if reusable rockets make launch cheap enough.
> "To achieve maximum selectivity and production of acetate from a direct CO2 feed, a two-step electrolyser system was demonstrated to convert CO2 to CO and then CO to acetate through a tandem process ... [stage one] produces a gaseous product stream containing CO, H2 and trace CO2... The gas product stream was then fed to the cathode chamber of the CO electrolyser... By maximizing the conversion of the first and second electrolysers, as well as specifically targeting acetate over other multi-carbon products, this system was able to achieve a single-pass conversion of CO2 to acetate of 25%..."
That's a respectable yield, but it doesn't look too easy to scale up. That's typical for research prototype work like this (iridium anode seems tricky). They're also using 100% CO2 as the feed gas so there's a preconcentration step from atmospheric CO2 required (400ppm starting -> 100% pure takes some energy input).
Seems fairly promising, they were getting 0.19 g of yeast (marmite basically, or nutritional yeast) per g of produced acetate. Mars colonists take note.