elementcollector1
International Hazard
Posts: 2684
Registered: 28-12-2011
Location: The Known Universe
Member Is Offline
Mood: Molten
|
|
Trouble with Chitin Bioplastic
I recently had shrimp for dinner, and on a whim felt like extracting the chitin from the shells and making something with it. I followed the procedure
in this link, with a few differences:
-Desproteinization was run for 24 hrs at room temperature with 2 wt.% NaOH, and then a final run was made at approx. 70 degrees C under a fresh
solution for 15 minutes. This changed the color of the shells from brown to red-orange (same color as cooked).
-Demineralization, in accordance with a different paper, was run under 0.25 M HCl at ambient temperatures for 15 minutes. No change in the chitin was
observed.
There were still orange bits sticking to the clear chitin shells, so I decided to put most of it back under 2% NaOH at ambient temperature for more
protein digestion and tried to see if some of it was soluble yet. To do so, I weighed out 7 grams (target was 6 grams) of the wet chitin material and
added to it 200 mL of white vinegar (~5% aq. acetic acid) in accordance with the attached paper, also available in the Sciencemadness Library. As of 3
hours in, little has changed - the clear shells are still visible in the solution. They appear to be more flexible now, so maybe what I'm seeing is
some leftover proteins, or just a thinner chitin shell that has lost its hardness? Hard to say. Does anyone have any experience with this exercise?
Attachment: hudson2015.pdf (1.4MB)
This file has been downloaded 262 times
Elements Collected:52/87
Latest Acquired: Cl
Next in Line: Nd
|
|
|
NEMO-Chemistry
International Hazard
Posts: 1559
Registered: 29-5-2016
Location: UK
Member Is Offline
Mood: No Mood
|
|
If you look in references, I posted asking for journal supporting information. The material was supplied and is in refs. Its from the journal of chem
ed, the supporting info goes into how to do the part your on about.
http://www.sciencemadness.org/talk/viewthread.php?tid=77654
I was also interested in it, Prawn and shrimp are big industry in Scotland, they have alot of waste product that would be great material!!
The other journal articall mentions crab, i found crab shell didnt work as well, no where near it!! Turns out its mainly the flimsy fin like bits on
crab legs, that are the only bits worth using. But those huge mini lobster things, that the Scottish call prawns, they are good.
But what the English call prawns are much much better for this. I will hunt down some pics to explain which is which 
[Edited on 24-1-2018 by NEMO-Chemistry]
Ok these are what the Scottish call Prawns, The english call them Tiger prawns or langoustine.
https://www.citarella.com/media/catalog/product/cache/1/imag...
These are what the Scottish call shrimp and I think the Americans do, the English call them Prawns.
http://img.delicious.com.au/26l_TlEG/h506-w759-cfill/del/201...
I couldnt find a pic of English shrimp, but they are like tiny clones of what they call Prawns.
[Edited on 24-1-2018 by NEMO-Chemistry]
|
|
|
NEMO-Chemistry
International Hazard
Posts: 1559
Registered: 29-5-2016
Location: UK
Member Is Offline
Mood: No Mood
|
|
Really sorry, i just realized I linked the wrong file!!!
I thought I had uploaded the Chitin one to refs. I will dig it out for you, there is also a thread i started but cant find now, i ask about the same
thing.
I did get it working in the end, but I started from cooked material. I havnt tried non cooked yet, on my tablet I have the papers I used. I did this
as one of my last projects at school, a kind of demo about bio plastic yada yada. Once you get it working its so easy, but like you I had problems at
the start, i still dont know why my first attempts failed.
Check this thread out
http://www.sciencemadness.org/talk/viewthread.php?tid=77221#...
[Edited on 26-1-2018 by NEMO-Chemistry]
|
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
