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Taking Radioactive Contaminants From Water With Shells

samzenpus posted about 3 years ago | from the three-shells-clean dept.

Earth 50

RedEaredSlider writes "Crab shells may soon be used to take radioactive contaminants out of water. Joel Pawlak, an associate professor of forest biomaterials at North Carolina State University, has developed a material similar to foam rubber that absorbs water and attaches to molecules dissolved in it, leaving pure and potable water behind. The material is a combination of hemicellulose and chitosan. The first comes from wood and is extracted by the ton in the paper-making process. Chitosan is extracted from ordinary crustacean shells — primarily crab, shrimp and lobster — by treatment with hydrochloric acid and then sodium hydroxide."

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It better be big (-1)

Anonymous Coward | about 3 years ago | (#35815794)

I hear the Pacific ocean has a fair bit of radioactivity at the moment

Re:It better be big (1)

Nexus7 (2919) | about 3 years ago | (#35817162)

It isn't even clear, from the article, how much is needed.

"... each gram of polymer will remove about 1.3 to 1.7 grams of contaminants... wants to get the material to a 100-to-1 ratio, in which a single gram of it can filter 100 grams of water."

Pick a unit guys, either use # grams of water/ # grams of polymer, or use # g contaminants/# g water. As it is, it isn't clear what they're aiming for relative to where they are.

Meanwhile a crowd of crab, shrimp and lobster ... (2, Funny)

PolygamousRanchKid (1290638) | about 3 years ago | (#35815814)

... are planning a march on Washington to protest.

Chitosan is extracted from ordinary crustacean shells — primarily crab, shrimp and lobster — by treatment with hydrochloric acid and then sodium hydroxide


Hmmm . . . that is one treatment that I will try avoid, if possible . . .

Re:Meanwhile a crowd of crab, shrimp and lobster . (2)

lxs (131946) | about 3 years ago | (#35815924)

Almost sounds like an acid-base extraction. Is it an alkaloid?

Re:Meanwhile a crowd of crab, shrimp and lobster . (2)

andrea.sartori (1603543) | about 3 years ago | (#35815996)

A polysaccharide.

Re:Meanwhile a crowd of crab, shrimp and lobster . (2)

lxs (131946) | about 3 years ago | (#35816076)

So it is, but there is still that dangling amine group on the monomer which would be susceptible to acid base extraction if you'd find a suitable non polar solvent.

Re:Meanwhile a crowd of crab, shrimp and lobster . (2, Funny)

Anonymous Coward | about 3 years ago | (#35816114)

It's a polysaccharide, in which some of the saccharides are D-glucosamine, which is basic.

Re:Meanwhile a crowd of crab, shrimp and lobster . (0)

Anonymous Coward | about 3 years ago | (#35815946)

Is it worse than radioactive crabs?

Re:Meanwhile a crowd of crab, shrimp and lobster . (0)

Anonymous Coward | about 3 years ago | (#35818986)

Won't affect slashdotters - they are not likely to catch crabs

Re:Meanwhile a crowd of crab, shrimp and lobster . (1)

Meski (774546) | about 3 years ago | (#35825668)

Let me put it this way: You won't need a glow-in-the-dark condom afterwards. And you won't need one at all, if you're just seeking to prevent contraception.

Re:Meanwhile a crowd of crab, shrimp and lobster . (1)

lazy genes (741633) | about 3 years ago | (#35822920)

if they keep using water cannons to spray anti nuke demonstrators, they will wear them out before they get a chance to cool down a melted core.

Sharp shooting (0)

Anonymous Coward | about 3 years ago | (#35815904)

Radioactive contaminants are very small. It's going to take a lot of shells and excellent aim if you want to take out all contaminants.

Re:Sharp shooting (1)

tripleevenfall (1990004) | about 3 years ago | (#35817408)

The same application of common sense didn't stop people from demanding that the government buy up Kevin Costner's miracle machines to clean the entire gulf of oil, either.

Three Shells (4, Funny)

narcc (412956) | about 3 years ago | (#35815974)

We've known for years that three shells is all you need to remove common contaminants. Now, if only someone would post instructions...

Re:Three Shells (0)

Anonymous Coward | about 3 years ago | (#35816062)

We've known for years that three shells is all you need to remove common contaminants. Now, if only someone would post instructions...

He doesn't know how to use the three seashells!

Re:Three Shells (0)

Kamiza Ikioi (893310) | about 3 years ago | (#35816422)

He doesn't know how to use the three seashells!

Thanks a lot you shit-brained, fuck-faced, ball breaking, duck fucking pain in the ass... So much for the seashells. See you in a few minutes.

Re:Three Shells (1)

Kamiza Ikioi (893310) | about 3 years ago | (#35817502)

It's the line from Demolition Man. I hate 13 year old mods who don't get old movie references.

Re:Three Shells (1)

Abstrackt (609015) | about 3 years ago | (#35817756)

Demolition Man is an old movie? Jeez, I should probably be telling kids to get off my lawn then....

"But there's just one thing I wanna know... How's that damn three seashell thing work?"

Explanation... or three... (1)

denzacar (181829) | about 3 years ago | (#35818314)

There's even a diagram on how to use them here. [i-mockery.com]

But, considering what is seen here, [poopreport.com] I do believe that something along the lines of wash-dry-perfume bidet is actually the correct answer.
Or should be.

Re:Three Shells (0)

Anonymous Coward | about 3 years ago | (#35816704)

We've known for years that three shells is all you need to remove common contaminants. Now, if only someone would post instructions...

good one... took me a while to pick that one up!!!

A timely discovery (1)

Intrepid imaginaut (1970940) | about 3 years ago | (#35815990)

If it works for radioactivity, could it work for almost anything? I mean could you literally put blood in one end and get clean water out the other? Not sure where I'm going with this but intersting...

Re:A timely discovery (1)

RockDoctor (15477) | about 3 years ago | (#35826678)

You could put (say) blood in at one end and get potable water out at the other end, along with a plugged and useless filter and a significant quantity of "blood concentrate". This is generally true for all filtering systems, and the more effective the filter, the faster it happens.

SOME (not all) filtering systems can be reverse-flushed to regenerate them, but for that, you need a supply of potable water to do the flushing with (otherwise you'fe got a filter contaminated on both sides.

Things get more complicated with chemically active filtering systems - ion exchange resins, semi-permeable membranes, etc. - but for simple systems, filtering is a thermodynamic problem, and the first and second Laws apply

  • First Law : you can't win.
  • Second Law : you can't even break even.

Which is not to say that filtering is useless ; sometimes you have energy available, but need to convert it to uncontaminated solvent ; other times, you're not obligated to "close the cycle" by regenerating your original uncontaminated filter.

same trick tried on genuine american natives (0)

Anonymous Coward | about 3 years ago | (#35816002)

"just accept this mere bag of shells, as a token of our gratitude" they (chosen ones 'discovery' team) bespoke onto them, who knew no words. what happened next, & ever since, brings us back again to our own plight. one less cup of coffee? try even harder to pretend it's ok? we do whatever we have to do?

thoughtful thursday, time conceals all wounds (0)

Anonymous Coward | about 3 years ago | (#35816036)

that's likely how fatal friday got its' impetus. even in the pitchest of darkness, there is light.

the truth, having been on extended exile, has made itself available again, including some of it's favorite tenants; math, science, history & life, for those who care to partake. on to babylon.

search?q=recursion (1)

atari2600a (1892574) | about 3 years ago | (#35816004)

So we're going to take parts of wildlife apart to clean the environment we destroyed to save the wildlife? Interesting... I'm a little curious how they'll COLLECT the shells. Are we going to buy the byproducts of a factory that produces frozen pre-made seafood?

Re:search?q=recursion (1)

gman003 (1693318) | about 3 years ago | (#35817302)

Probably. Just look at how many crabs are eaten. Now look at how many of those sold have a shell still attached. It's turning waste from two different sources into a usable solution to a major problem - and one that's just become even more significant.

Did anyone else double take (1)

Compaqt (1758360) | about 3 years ago | (#35816012)

on how exactly they were going to remove radioactivity with a shell [wikipedia.org], and if so, which [gnu.org] one [mkssoftware.com] ? [zsh.org]

Re:Did anyone else double take (2)

spirito (1552779) | about 3 years ago | (#35816134)

rm -rf radioactivity perhaps? Seriously, if you don't know the basics, do not post on slashdot!

Re:Did anyone else double take (1)

Compaqt (1758360) | about 3 years ago | (#35816566)

It won't work without a forward slash. Forward slashes counteract radiactivity:

rm -rf / radioactivity

BASH Shell? (1)

Rik Sweeney (471717) | about 3 years ago | (#35816044)

I guess they'll be using the shell to BASH the radioactivity out.

*ba da boom tish*

Thank you, I'm here all week!

And how much will is cost? (0)

Anonymous Coward | about 3 years ago | (#35816118)

Chitosan, also know as Glucosamine, is currently being sold as a dietary supplement.

Its not particularly cheap either, and these are just a bunch of pills.

How much of this shit would you need to filter tons of radioactive water?

Re:And how much will is cost? (3, Insightful)

budgenator (254554) | about 3 years ago | (#35816218)

I don't think that because glucosamine as a dietary supplement is pretty expensive, it follows that that glucosamine as an industrial reagent will be as well. The prices of medicines and supplements rarely are cost of production and distribution plus reasonable markup.

World of Warcraft (1)

El Lobo (994537) | about 3 years ago | (#35816126)

The summary sounds like a WoW quest. It should have ended with a "Lobuno, please could you get me 12 crab shells from the Abyss?". Sorry... too much WoW this last mon

branson; world wide airlifts of harmed civilians (0)

Anonymous Coward | about 3 years ago | (#35816188)

to safe inland shelter, in still livable areas, in other parts of the world, like utah.

this guy is whack? can he do it? can we help him? is there room?

if anybody could ever get their cherries back? let's

We're already doing this! (1)

T-Bucket (823202) | about 3 years ago | (#35816318)

I thought "This is the same way we're removing terrorists from Iraq!". But wait, different kind of shell...

Interesting (2)

_0xd0ad (1974778) | about 3 years ago | (#35816578)

Sounds like they're combining the properties of both a cationic and anionic polymer with the idea of maximizing the surface area on which the adhesion occurs (similar to activated carbon).

Basically, in layman's terms... most things that dissolve in water form ions (either positively or negatively charged), which can be removed by their electrostatic adhesion to oppositely-charged ions. According to TFA, this polymer foam has both positively and negatively charged ions at its surface for the dissolved ions to adhere to (perhaps someone with more knowledge of organic chemistry could tell me if this is fairly unique? I've never heard of a polymer which was both cationic and anionic). Since the ions actually cling to its surface, the surface area should be maximized (the principle behind an activated carbon filter), which in this case they're doing by making it into a foam.

I volunteer (0)

Anonymous Coward | about 3 years ago | (#35816670)

I volunteer my services to manufacture said crab shells. I'll require a hearty supply of live crabs, a really big boiling pot, and some Old Bay. I'll get the shells to you in a few months.

Lobsteron the Terrible! (1)

DarthVain (724186) | about 3 years ago | (#35817276)

What they didn't tell you is that it will birth Lobersteron the Terrible! Sucking all that radiation into its carapace he will grow to the size of a large skyscraper and terrorize the countryside. Fortunately he will probably cross paths with Crabucon the Munificent and will duke it out, the loser slinking back into the ocean. Of course the urban devastation will be horrible, but whatcha gonna do... Hopefully it will be DJ'ed by the Beastie Boys.

Add "radioactive" to get news coverage (1)

Caption Wierd (1164059) | about 3 years ago | (#35817382)

There is no difference in removing radioactive materials from seawater than removing non-radioactive materials. Each atom of I-131 is exactly Iodine until that moment when it decides to decay and transform into Xenon-131, a stable isotope. This method may be useful only if it can remove contaminants at very low mass concentrations. The total amount of I-131 released at Fukushima is only around 100 grams, assuming the values in the news are correct. The reported concentration at one of the outfalls, at several thousand times the drinking water limits, works out to about 0.03 PPB.

ceramic filters anyone? (1)

Herve5 (879674) | about 3 years ago | (#35817574)

I recently shifted from ordinary disposable filters (that cost an arm and a leg per year for the average family here in Europe) to a swiss-made ceramic-based one that can be cleaned after a while, and is expected to last years (I indeed used it for one year now without wear).
I understand this method is more for bacterias etc. rather than ions, so maybe the crab-related thingie could be set just after ;-)
For this now I also have a carbon flter that removes some ions (chlore among others) but certainly not radioactive iodine :-D
All in all I feel I now have a more durable system, without throwing aways kilograms of disposable filters every year...

Re:ceramic filters anyone? (1)

_0xd0ad (1974778) | about 3 years ago | (#35817774)

The principle here is not actual filtration (such as is done by your ceramic filters). It is actually the electrostatic attraction between charged ions. Rather than a lattice structure in which large impurities get "stuck", this is a surface to which impurities adhere. It's like fly-paper, or those cat-hair removers.

Making it into a foam is not designed to trap the impurities, but rather to give the impurities a lot of surface area to stick to. The impurities don't get stuck because they can't find any open path through the material; they get stuck because once they touch the surface, they're stuck.

Won't work on heavy water (1)

tirerim (1108567) | about 3 years ago | (#35818078)

Since this relies on chemical properties of dissolved radioactive elements, it shouldn't have any effect on deuterium and tritium bound up in water molecules. Deuterium isn't actually radioactive, but tritium is, so there could still be some radioactivity. I don't know how much tritiated water is likely to be contained in conatminated water, though (it might vary depending on the source), so it might not actually be that much of a problem.

Marketting BS (0)

Anonymous Coward | about 3 years ago | (#35819408)

The entire article is marketing BS. It's akin to all the crap that came out immediately after BP massive oil leak.

Too bad that radioactive, water soluble substances, will simply "dilute to undetectability" in the ocean. Even with our ability to almost count single atoms of radioactive materials, it will not be possible to find the radioactive material from Japan.

For example, France exploded a nuclear bombs in the Pacific until end of 1995. Where did that massive amount of radiation go??

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