4 ms·

"Reducing the number of steps might lead to some amazing efficiency breakthrough, but if you mention the step reduction and then stop, I'm going to assume it do

"Reducing the number of steps might lead to some amazing efficiency breakthrough, but if you mention the step reduction and then stop, I'm going to assume it doesn't." It doesn't (yet) and they do mention it: "To date, maximum measured values of efficiency are still in the single digits, namely 5.6% for pure CO2-splitting and 4.1% for co-splitting CO2 and H2O." Not great so far. Also Cerium is a rare earth, even though quite widespread.

adrian_b 3y ago
It is by far the cheapest rare-earth metal. It is even much cheaper than it could be expected from its abundance, because it accumulates as a byproduct of producing REEs for which there is a higher demand, e.g. neodymium, and its storage is expensive for the REE producers. They would be almost willing to give it away for free, to get rid of it. In recent years most public information about the current price of metals has disappeared, but 10 years ago the price of pure cerium was around $10/kg, in the same range with the prices of pure copper, pure chromium or pure titanium. Cerium compounds, like the ceria used here, can be significantly cheaper than the metal (because the metal requires a lot of energy for extraction). A Google search indicates that the current price of ceria (i.e. cerium oxide) is around $1.65 per kilogram, so the price of ceria must be a negligible part of the price of such a CO2 splitting device.
- hutzlibu 3y ago
  Well, under the assumption that this is the great next thing and mass production starts, prices will surely rise, but all in all yes, it likeley will not be a bottleneck, efficency is mainly the problem.
Animats 3y ago
Having to run the reaction at 1500°C is a bit much. They had to use a big solar mirror concentrator to get up to that temperature, and they're not producing much product. There are so many of these bad schemes for making "green" burnable fuels by splitting CO2 that there is probably some group subsidizing these articles. Not to the point that the technology actually works, just to the point that it generates PR.

adrian_b 3y ago

It is by far the cheapest rare-earth metal. It is even much cheaper than it could be expected from its abundance, because it accumulates as a byproduct of producing REEs for which there is a higher demand, e.g. neodymium, and its storage is expensive for the REE producers. They would be almost willing to give it away for free, to get rid of it. In recent years most public information about the current price of metals has disappeared, but 10 years ago the price of pure cerium was around $10/kg, in the same range with the prices of pure copper, pure chromium or pure titanium. Cerium compounds, like the ceria used here, can be significantly cheaper than the metal (because the metal requires a lot of energy for extraction). A Google search indicates that the current price of ceria (i.e. cerium oxide) is around $1.65 per kilogram, so the price of ceria must be a negligible part of the price of such a CO2 splitting device.

hutzlibu 3y ago
Well, under the assumption that this is the great next thing and mass production starts, prices will surely rise, but all in all yes, it likeley will not be a bottleneck, efficency is mainly the problem.

Animats 3y ago

Having to run the reaction at 1500°C is a bit much. They had to use a big solar mirror concentrator to get up to that temperature, and they're not producing much product. There are so many of these bad schemes for making "green" burnable fuels by splitting CO2 that there is probably some group subsidizing these articles. Not to the point that the technology actually works, just to the point that it generates PR.