jellywerker
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test tube scale setup?
I am entertaining the idea of a small (but not microscale) test tube setup for doing things on the scale of 25ml to 75ml (so no containers bigger than
250ml) The small size is mostly for safety and cost, and a larger setup would be useless as I don't want to work with any larger quantities. I have
been inspired by another person's setup I saw here, based on 50ml centrifuge tubes.
I am interested in energetic materials along with chemical synthesis and some work with extracting organic compounds (not drugs for anyone getting a
red flag, things like caffeine, capsacin (not altogether pure though, it's nasty stuff then) and bio-fuel related research)
I have been frantically doodling possible apparatus and setups for a few days now, but came to the conclusion that with my nonexistant glassworking
experience, I doubt I could do anything more than bend tubing, making creating things like a test tube scale condensing column out of my reach. So I
decided to post here looking for ideas and tips on what to get. I know there have been many threads posted here on the subject, but I thought mine was
somewhat more unique and couldn't be answered through searching the forum.
As for what I am looking at, here is a somewhat abstract list:
50-250ml beakers
test tubes (the system would be based on 18x150mmx28ml tubes I'd say, but with smaller and larger tubes for various purposes)
a condensing column (to scale, I'm not sure if I could make my own, but I'd like too. I think a full 300mm leibig is much too large and complex for
the mostly simple distilling I'd be doing, a glass tube with nipples on each end for water tubing and a robber stopper on each end with a hole and a
piece of glass rod inserted through the whole thing would be fine I'd think)
some form of small desicating dish (could simply be a tupperware)
50-250ml boiling flasks (250ml so I have more room for concentrating weak OTC chemicals)
a reflux apparatus (most likely a custom doodled one based on several seen in the prepublication forum, as this is one thing that simply requires a
double holed stopper and bent tubing, I think I can do it  )
test tube and flask stands (copper or steel tubing mounted to particle-board based with plastic clamps? Small ones from the hardware store should be
heat resistant enough)
an amount of small bottles to hold chems and synths
As for equipment, I figure a normal stirrer/heater won't work with test tubes, so I planned on a bunsen burner (lp) or an alcohol burner, probably go
with the alcohol burner first and upgrade to the bunsen burner when I have some more money. Stirring on such a small scale I figure can be
accomplished by hand or with a small fan speed regulator coupled with motor spinning a stick with 2 magnets on the blades that could spin a tiny 10 or
12mm stirring bar. I would probably be easier to make small and fit under things anyways.
Anyways though, I figure I could do something like this for maybe $150 or so, maybe less.
So, any ideas or suggestions?
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Magpie
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Mood: Chemistry: the subtle science.
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For organic work I'd recommend a kit with 19/22 taper ground glass joints. They are not cheap new but you see them often on eBay. The largest flask
is 500 mL, the smallest 25 mL. I have one and like it.
The single most important condition for a successful synthesis is good mixing - Nicodem
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jellywerker
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I am not doing purely organic work though, so an organic kit would probably not fill my needs, at at $150+ on ebay, I could probably piece together a
similar setup from single auctions and such.
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bereal511
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I'm sure you could find something good on eBay that's being auctioned. I got my 19/22 distillation setup for about $80. Good stuff. Just gotta be
patient with it if you're interested. And they're not just for organic work, I mean if you ever need to make nitric acid from sulfuric or anything of
that bit, kits are nice to have around.
As an adolescent I aspired to lasting fame, I craved factual certainty, and I thirsted for a meaningful vision of human life -- so I became a
scientist. This is like becoming an archbishop so you can meet girls.
-- Matt Cartmill
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jellywerker
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Location: Northwest United States
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Well, with a closer look at condensers (and some rooted around Tacho's very helpful low cost chem site), I realiszd it doesn't matter what the jacket
is on a leibig, as the vapors never leave the central tube. So I'm going to make one out of pvc for the outer jacket with a 7mm glass rod running
through it. I'll epoxy on some hose barbs and wrap teflon tape around the holes where the tube enters and exits to waterproof it, and I think it
should work just fine. This makes things a lot easier for me as I can just custom craft a condenser real quick to my needs. With that out of the way,
I still do need to know if rubber stoppers are ok to use to connect that glass rod to a boiling flask, especially for distilling nitric. Will nitric
corrode a rubber stopper? I had intended to use one with two holes in it, one wrapped with teflon tape and holding a thermometer, and the other (also
wrapped with teflon for a good seal) connected to the glass rod of the condenser.
Also, I'm looking at getting some stuff from Avogadro's Lab Supply on ebay, but the stuff he sells seems to be bomex. Is that ok for a user like me or
should I bite the bullet and look around for pyrex/kimax stuff?
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Magpie
lab constructor
Posts: 5939
Registered: 1-11-2003
Location: USA
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Mood: Chemistry: the subtle science.
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Some recommendations for your safety...
HNO3 will tear up rubber and your lungs. I wouldn't make nitric acid unless I had a gas tight set-up and a hood.
I admire your determination to get experimenting. But you are not starting an ordinary hobby here. A little patience is in order. Start with some
inherently safe experiments and get some experience before jumping into something like making nitric acid.
The single most important condition for a successful synthesis is good mixing - Nicodem
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jellywerker
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Registered: 17-9-2006
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Ok, so besides some safer experiments, would you reccomend teflon or similar plugs? I also read on here that covering a stopper in saran wrap makes it
nitric proof, is this true?
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