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Taking Radioactive Contaminants From Water With Shells
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."
... 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
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Hmmm . . . that is one treatment that I will try avoid, if possible . . .
Schroedinger's Brexit: The UK is both in and out of the EU at the same time!
Almost sounds like an acid-base extraction. Is it an alkaloid?
We've known for years that three shells is all you need to remove common contaminants. Now, if only someone would post instructions...
Required reading for internet skeptics
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...
A polysaccharide.
Mostly harmless.
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?
I for one welcome our radioactive crab overlords!
on how exactly they were going to remove radioactivity with a shell, and if so, which one ?
I'm not a lawyer, but I play one on the Internet. Blog
I guess they'll be using the shell to BASH the radioactivity out.
*ba da boom tish*
Thank you, I'm here all week!
Summation 2
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.
It's a polysaccharide, in which some of the saccharides are D-glucosamine, which is basic.
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
It's time to realise that Abble's products are the biggest abomination these days. Just say NO to the dumb iAbble way!!
Eat lobster and save the world!
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.
Apocalypse Cancelled, Sorry, No Ticket Refunds
I thought "This is the same way we're removing terrorists from Iraq!". But wait, different kind of shell...
I knew shell would save the world, but which one? csh, ksh, bash, zsh, ...
I8-D
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.
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.
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.
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.
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.
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). ;-) :-D
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
All in all I feel I now have a more durable system, without throwing aways kilograms of disposable filters every year...
H.
Herve S.
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.
There's even a diagram on how to use them here.
But, considering what is seen here, I do believe that something along the lines of wash-dry-perfume bidet is actually the correct answer.
Or should be.
Mit der Dummheit kämpfen Götter selbst vergebens
I want to take radioactive contaminants from water without shells in it.
Seven puppies were harmed during the making of this post.
In soviet waters the crabs radiate you.
"The laws of science be a harsh mistress." --Bender
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.