Chemist Uses CO2 to Convert Seawater into Drinking Water

https://www.ineffableisland.com/2020/10/chemist-uses-co2-to-convert-seawater.html

by SQL2219 • 6 years ago

217 49 6 years ago

ggm2• 6 years ago

How bio-active is the diamine, and how much remains in the potable water?

What happens to the CO2 afterward, if the salt is released? If this doesn't bind the CO2 permanently then its only about water desal. If it bound the CO2 it has dual-purpose.

refurb• 6 years ago

You're asking the right questions! Even a few PPM of the diamine left in the water is going to be an issue either due to toxicity or if non-toxic, water quality (i.e. taste and perception of potability).

The "switchable" chelating agent is pretty interesting, but I haven't been close enough to know if this is groundbreaking or just an advancement of an exiting phenomenon.

I might be a major cynic here, but my guess is that this is really cool science and like a lot of cool, basic science, the researchers need to find a practical use for it. That helps translate "cool basic science" into "existing new technology".

My PI did it when I was in graduate school - we always talked about our new molecules as being potential cancer treatments when really the focus was on the basic organic chemistry. It's a lot easier to win grants saying you're developing "new anti-cancer compounds" than being honest and saying your research is focused on the development of "novel chalcogen compounds that undergo pericyclic rearrangements to form strained heterocycles".

ggm2• 6 years ago

A lot of deep groundwater (associated with gas, oil) is both salty, and gassy. If this technique is about converting mine waste to semi-potable for use in agriculture, or mining, and also uses the CO2 on-hand, and salt on-hand, its a virtuous industrial circle.

I'd hate it since it would be monetizing part of the mining industry I don't like, but it makes economic sense in the narrow. If diamine is bad, and gets into the food chain this wreaks longterm harm. If the liberated salt is bad, likewise.

I tend to "stop the mining" but understanding the pressure of water issues on mining and farming, there may be huge upsides here.

vbezhenar• 6 years ago

Most of water is used for technical purposes, not for drinking. Like washing hands, body or dishes. If it's safe for that, that would be huge achievement is this process is cheaper than conventional methods.

omosubi• 6 years ago

This is the original press release including video clip https://news.ku.dk/all_news/2020/09/chemist-uses-co2-to-conv...

aazaa• 6 years ago

The technology works by adding the compound diamine to saltwater. The type of diamine used is CO2-responsive, meaning that the substance’s behaviour can be controlled when it comes into contact with CO2. The diamine binds with the added CO2 and thereafter acts as a sponge to absorb the salt, which can then be separated. The entire process takes 1-10 minutes. Once the CO2 is removed, the salt is released again – allowing for the chemicals to be reused for several more rounds of desalination.

This article leaves a lot to be desired.

There is no compound called "diamine." Diamines are a class of compounds. Without knowing which one is being used, there's not much of a discussion to be had. We can say nothing about practicality or environmental impact, not to mention a host of other issues.

What may be happening here is the formation of a dicarboxamide, which then does something. That carboxamide formation is not likely to be reversible at room temperature.

The article has no link to the primary paper, where issues like this could readily be addressed, and there is absolutely no excuse to ever neglect to do so in 2020.

neltnerb3• 6 years ago

"Currently, the CowaTech technology is at technology readiness level (TRL) 2-3."

Which, for the uninitiated, means it is starting feasibility testing and are just barely starting development. I would bet they haven't solved that in any significant scale, that sort of issue wouldn't have come up yet at their development level.

taheca• 6 years ago

This thread is why I love hackernews

jerome-jh3• 6 years ago

Intuitively, I'm not a specialist, if water desalinization with there compound was more energy efficient than the current process, they would be on course to demonstrate it. They would not be working on "water bottles [...] for outdoor activities". Since they estimate a 50% efficiency gain would make it viable, it probably consumes about 125% energy compared to the current process.

segfaultbuserr2• 6 years ago

I was unable to find the source. I searched the name "Ji-Woong Lee" of University of Copenhagen, I found his bibliography [0] and Twitter account [1], but I was unable to find any paper on CO2-enabled saltwater desalination. The only CO2-related paper was about its applications in organic synthesis, "CO2-Enabled Cyanohydrin Synthesis and Facile Homologation Reactions" [2].

But he did repost a press release on Twitter. Perhaps the paper is not published yet?

[0] https://scholar.google.com/citations?hl=en&user=RplTooAAAAAJ

[1] https://twitter.com/theleelab_chem

[2] https://chemistry-europe.onlinelibrary.wiley.com/doi/10.1002...

jitbit• 6 years ago

Googling in Danish helps: https://nyheder.ku.dk/alle_nyheder/2020/09/kemiker-omdanner-...

(and at he bottom there's a link to the r&d company he founded)

majinuub• 6 years ago

I tried to find a paper too, but couldn't find anything. I did find a little more information on CowaTech's site, but its not much more than what we already know: https://www.cowatech.dk/technology

boomboomsubban• 6 years ago

Without knowing which one is being used, there's not much of a discussion to be had. We can say nothing about practicality or environmental impact, not to mention a host of other issues.

Wouldn't this information likely be patented, which could explain much of the press release secrecy?

krageon• 6 years ago

A patent would mean it was publicly available information. You're thinking of a trade secret. In any case, this won't apply to an actual paper (and without a paper, what are we talking about?) because the paper is supposed to describe what is going on.

jojobas2• 6 years ago

A 5 dollar note says this Maxwell Daemon process has to be on par with reverse osmosis in terms of energy consumption, with the added complication of exotic chemicals.

All the dry regions are rather sunny, solar reverse osmosis sounds like a no-brainer.

newyankee• 6 years ago

Honestly the ideal contraption would be something that can harness the solar on the sea directly. That would be something especially if it is in the form of fishing nets at surface.

TimTheTinker• 6 years ago

More info from the Danish company that is commercializing this process: https://www.cowatech.dk/technology

Currently, the CowaTech technology is at technology readiness level (TRL) 2-3.

m463• 6 years ago

I've never heard of "technology readiness level" but it is fascinating and came from NASA

the original scale went 1-7 where 1 meant "Basic Principles Observed and Reported" and 7 meant "System Adequacy Validated in Space"

The current scale(s) seems to be 1-9, and my take on 2-3 is "press release" :)

https://en.wikipedia.org/wiki/Technology_readiness_level

basicplus2• 6 years ago

Carbamate Formation in Aqueous - diamine - CO2 Systems

https://www.sciencedirect.com/science/article/pii/S187661021...

extropy• 6 years ago

That's 7 years old by a Norwegian university, unlikely to be the thing.

heyflyguy• 6 years ago

I know I am way oversimplifying this. Last week I made a trip to sand hill road and had some fun. My most interesting takeaway from the trip wasn't any of those meetings, it was the many signs along I-5 between LA and SF. Yall need water, bad. I hope this is a potential solution.

softblush• 6 years ago

What a cryptic message. How is somebody from outside the USA supposed to understand what you are saying?

nullc2• 6 years ago

By the power of goooooglllleeeee!

https://www.kqed.org/bayareabites/96228/who-is-behind-those-...

codemusings2• 6 years ago

I mean it is cryptic. But it's not exactly a secret that California suffers from water shortages.

fbn79• 6 years ago

Am I wrong or the technology can be used one day to create Stillsuit (https://dune.fandom.com/wiki/Stillsuit) as described in Dune by Frank Herbert?

tsimionescu• 6 years ago

We already have other methods of desalinating water, so not sure why this would be a step forward toward that idea. Also, a Stillsuit was not supposed to desalinate saltwater, but to purify urine and sweat, which contain many more chemicals than just NaCl.

scoot• 6 years ago

It seems like you would roast to death before you die of dehydration.

Knufen• 6 years ago

This is pretty cool. I do organic synthesis in the lab right next to Jiwoong Lee, two of my good friends work on this project. It is not as amazing as the article makes it sound. Though low in energy it needs pressure and no one wants to drink the "diamine" compound, so added energy to remove this is needed. Give it 10-15 years.

Pick-A-Hill2019• 6 years ago

Thanks for posting. I was curious about the potability of the diamine compound and your post answers it perfectly :)

devy• 6 years ago

Can't post this link to Facebook as they ban this site ineffableisland.com.

Here is the reason:

"This URL goes against our Community Standards on spam: ineffableisland.com"

TheRealPomax• 6 years ago

There is precious little actual information in this article, and as the top comment already puts out, doesn't tell the whole story either.

hexbinencoded• 6 years ago

Thunderf00t busted video incoming. It's vaporware hype until proven otherwise.

Chemist Uses CO2 to Convert Seawater into Drinking Water

Related Stories