Splinky
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First Nitration
I just tried to nitrate about 1.7 grams of cellulose in the form of cotton balls with the method used on brainfevers site. I dissolved 25 grams of
KNO3 into 30 ml of drain opener sulfuric acid, once the saltpeter had dissolved and the mix stopped warming up, I added the cotton and let it sit for
about ten minutes. When I fished the balls out I noticed that there was a lot of solidification in the mix and had to dig through the sludge like
mixture to get at the potential cellulose nitrate. They quickly sank into the water that I put them in and were solid in the center when I did.
Is this just the potassium sulfate that was left over from the KNO3+H2SO4 -> HNO3? I will neutralize and dry the wads so I can test them tomorrow,
but I wanted to ask if this was normal.
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Zinc
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I think that it is normal. The same thing happens to me when I use sodium nitrate/H2SO4. Use ammonium nitrate instead of potassium nitrate if you want
to avoid that.
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Splinky
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I just dried some of it partially, and a few strands took flame with much more vigor than regular damp cotton, so I guess it is okay. I think I'll
just wait until I get some real glass ware (did this in a glass seasoning jar) before I try again.
Edit: Now today it doesn't seem to be acting like what I have seen of cellulose nitrate, it fizzles for a bit before making a small poof. Is it
possible to have only partially nitrated it? I also think that I got a hint of sulfur when I lit a couple pieces of it, but I probably just didn't
wash it well enough to get out all of the potassium sulfate.
[Edited on 30-3-2008 by Splinky]
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ScienceGeek
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Did you completely submerge the cotton in the nitrating solution? If not, it would only be partially nitrated. If you did submerge it completely, I
don't see how it could only be partially nitrated...
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ordenblitz
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The thing that makes a lot of difference but most first timers overlook is dehydrating your cotton before nitration. Extra water is your enemy so I
would even go as far as to bake out your nitrate before mixing as well.
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ScienceGeek
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That's true, but in my experience insignificant as long as concentrated sulfuric acid is used.
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Splinky
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Yes, it was completely submerged. However I used Rooto and did not dehydrate the cotton or KNO3 beforehand, so the extra water route might be the
explanation.
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ScienceGeek
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But then the cotton should be partially nitrated as a whole, and not some part of the cotton more nitrated than another part...strange results you've
gotten there!
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Splinky
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Maybe the solidification of the sulfate prevented some of the cotton from getting into contact with acid. The whole mass is slightly yellowed,
probably from the dye in the acid.
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ScienceGeek
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The cotton becomes slightly yellow either way. That is due to the Nitrogen groups in the cellulose and also due to Nitrogen Dioxide. But your
explanation seems plausible!
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