[HN Gopher] Engineers develop a process to make formate fuel fro...
___________________________________________________________________
Engineers develop a process to make formate fuel from CO2
Author : westurner
Score : 54 points
Date : 2023-10-31 20:35 UTC (2 hours ago)
(HTM) web link (news.mit.edu)
(TXT) w3m dump (news.mit.edu)
| westurner wrote:
| "A carbon-efficient bicarbonate electrolyzer" (2023)
| https://www.cell.com/cell-reports-physical-science/fulltext/... :
|
| > _Carbon efficiency is one of the most pressing problems of
| carbon dioxide electroreduction today. While there have been
| studies on anion exchange membrane electrolyzers with carbon
| dioxide (gas) and bipolar membrane electrolyzers with bicarbonate
| (aqueous) feedstocks, both suffer from low carbon efficiency. In
| anion exchange membrane electrolyzers, this is due to carbonate
| anion crossover, whereas in bipolar membrane electrolyzers, the
| exsolution of carbon dioxide (gas) from the bicarbonate solution
| is the culprit. Here, we first elucidate the root cause of the
| low carbon efficiency of liquid bicarbonate electrolyzers with
| thermodynamic calculations and then achieve carbon-efficient
| carbon dioxide electroreduction by adopting a near-neutral-pH
| cation exchange membrane, a glass fiber intermediate layer, and
| carbon dioxide (gas) partial pressure management. We convert
| highly concentrated bicarbonate solution to solid formate fuel
| with a yield (carbon efficiency) of greater than 96%. A device
| test is demonstrated at 100 mA cm-2 with a full-cell voltage of
| 3.1 V for over 200 h._
| westurner wrote:
| "Aluminum formate Al(HCOO)3: Earth-abundant, scalable, & material
| for CO2 capture" (2022)
| https://news.ycombinator.com/item?id=33501182
| 1letterunixname wrote:
| Sigh. The PR department of universities are about selling IP,
| getting grant$ to fund their toys, and sometimes attracting
| PI's and students to do the work based on the university's
| reputation.
| stonogo wrote:
| What should they be focused on?
| readthenotes1 wrote:
| Educating students
| dv_dt wrote:
| There is a no-funding land that is needed to advance
| society. Between basic scientific research and advanced
| low probability engineering research no for-profit
| corporation is willing to find - so it's mostly the
| domain of the government allocating grants to
| universities and labs.
| Terr_ wrote:
| Relevant:
| https://phdcomics.com/comics/archive.php?comicid=1174
| 1letterunixname wrote:
| Sorry to pour cold dihydrogen monoxide on their press release
| birthday cake: It's not sequestration, so it's not all that
| useful. Take all the process losses to use the inputs as
| electricity directly, be it charging EV batteries or directly
| with mass transit motors.
| callalex wrote:
| What about weight-sensitive applications like aviation and
| shipping?
| 1letterunixname wrote:
| FF aviation should be abandoned because of the climate change
| implications. It's extremely inefficient. Large EV gliders
| are workable. Solar Impulse 2 was a record-setting PoC on a
| smaller, cheaper scale.
|
| Shipping by full EV maritime shipping is on the horizon.
| Hybrid cargo ships are already a thing. (Aasfjell)
|
| Rail shipping is extremely energy efficient. This is how most
| cargo should be transported. A global rail transport network
| should be seriously considered.
| mikewarot wrote:
| Waterborne shipping is even more efficient, we need to
| repeat the Jones Act in the US.
| jlaporte wrote:
| The headline number of 96% (in the original new release) is very
| misleading. What matters is not the fraction of gaseous carbon
| that ends up in the fuel (the yield), it's the energetic
| efficiency of the process. ie: Nobody will spend 100 Joules of
| energy to store, say, 1 Joule of energy. The paper says their
| process has low energy efficiency (low enough they don't seem to
| want to say the number)[1]:
|
| > ...rather than relying on the CO2(gas) feedstock, bipolar
| membrane (BPM) electrolyzers with aqueous bicarbonate HCO3-(aq)
| input were demonstrated (Figure S2b). In principle, the energy-
| intensive CO2 regeneration process could be circumvented. In
| practice, however, the BPM induces a large overpotential, causing
| * _low energy efficiency*_ , and it still suffers from CO2
| escape, low FE, low yield, and low operation lifetime. [**
| emphasis added]
|
| [1] https://www.cell.com/cell-reports-physical-
| science/fulltext/...
| pokstad wrote:
| Well not no-one. Maybe if you are on a spaceship and need to
| replenish your carbon-fuel-cell with your fusion reactor and
| can't waste any carbon.
| diroussel wrote:
| That pretty much is the definition of no-one.
| nabakin wrote:
| There have been a few suspect title changes on HN as of late
| but this would be a good one.
| silisili wrote:
| Is it feasible/possible to knowingly do that, and still 'win'?
| That is, power the process with nuclear or some renewable, not
| necessarily as a way to get fuel, but a way to get carbon out
| of the air?
| nomel wrote:
| This seems like far in the future, where the direct use of
| the nuclear wouldn't prevent more CO2 from being introduced
| into the atmosphere, than could be removed.
| skaushik92 wrote:
| Also, it could be wherever nuclear wouldn't be permissible
| otherwise (e.g floating in the middle of the Pacific Ocean
| extracting CO2 from the atmosphere, away from populations
| that don't want it nearby)
| cogman10 wrote:
| Yup, said another way, this would only really make sense if
| we are producing more energy than we can reasonably use and
| need to sink it somewhere.
|
| However, there are so many sinks for energy that I just
| doubt CO2 will be a priority any time soon. Desalination,
| for example, will almost certainly end up being a huge
| energy sink as the world gets hotter.
| whatever1 wrote:
| Exactly. You need a lot of energy to upgrade CO2 to something
| with higher enthalpy (fuel).
|
| Not sure why so much money has been spent on these
| thermodynamic dead ends.
| scythe wrote:
| The use case for all of these CO2 reduction methods that
| seems particularly interesting is if you capture the CO2
| _inevitably_ produced as a byproduct of cement production and
| then convert it into useful plastics. You avoid air capture
| and you get something that 's good for more than just
| burning.
| cogman10 wrote:
| We have so much plastic, I almost wonder if it would be
| easy enough to burn it, capture the CO2, and convert that
| into new plastic.
| cogman10 wrote:
| Yup.
|
| The problem we have is CO2 is mixed into the atmosphere at ~420
| ppm. Isolating just the CO2 and concentrating it enough for
| these processes to work is one of the major energy sinks.
|
| This is compounded by the fact that the energy it takes to turn
| CO2 back into fuel can never be less than the energy released
| by the fuel.
| wg0 wrote:
| It seems quest for energy isn't coming out of oil wells or coal
| and nuclear.
|
| Nothing about fusion, no feasible, practical and scalable energy
| storage on the horizon. Yet.
| stevage wrote:
| > even the best available practical hydrogen storage tanks allow
| the gas to leak out at a rate of about 1 percent per day
|
| Wow, I did not know that.
| kulahan wrote:
| Really hard to keep a molecule that small in one place for
| long! I've definitely heard that it really just flies out of
| steel containers at shockingly high rates
| starbase wrote:
| 96% efficient at converting feedstock to fuel, not 96% of energy
| efficient
___________________________________________________________________
(page generated 2023-10-31 23:00 UTC)