Non-Chemical How much weight will boiling flask bear?

[924T]

I'm looking at using a Reflux Condenser on top of a boiling flask or an Erlenmeyer (all 24/40 joints), and
I'm interested in finding out just how much weight (additional pieces of glassware) can be safely employed
with the flasks?

The 2 scenarios I'm considering are running 2 400mm Reflux Condensers in series, or 1 Condenser and
2 Chromatography reservoirs in series. There may very well be a Claisen adapter inline, too.

I've seen pictures of a rectangular grid with multiple clamps on it to hold various pieces of glassware in
laboratories (I don't know the correct name/term for such a thing)-------would something like that be
necessary to stabilize an 'array' like I would like to use?

Many thanks,

Mike

 

[Irons]

http://www.youtube.com/watch?v=fHEk2WFgmXQ

Note the use of clamps and support for the apparatus. Check out some of the other links as well.

 

[924T]

Irons,

It appears you recognized I never had organic chemistry, and sent me to the best possible youtube link to
get me up to speed on condensers and ground glass joints!

That then spun me off into an alternate universe of heating mantles, which I had never seen or heard of before,
and after some research here on the GRF, I was delighted to find out that a crockpot with a rheostat will work just as well
(if not better, and at a better {lower} price point, too).

I'm inclined to get some Staco variable transformers, rather than full-blown variacs to control the crockpot
temperatures----much heavier duty than rheostats.

Up next will be identification and pursuit of the correct type/size of ring stand clamps to hold the reflux
condensers in place, and some rings (a guy on sciencemadness.org has some rings for sale, up to 9" diameter).

Thanks again for steering me to the M.I.T. videos!

And, what kind of joint grease do you use on your glassware arrays?

Cheers,

Mike

 

[Irons]

Hi Mike,
For sealing the glassware joints, I recommend : Perfluoropolyether PFPE PTFE Grease Oxygen 400ºF Krytox (cut and paste from a listing on fleabay). It's not cheap, but you only use a tiny amount.

..also Keck Clips to hold the joints together. Be warned that there are cheap knock-offs for sale. The genuine ones are made in Germany or Switzerland, which is imprinted on the clip. They are color-coded: T/S 24= green, T/S 19= blue, T/S 14= yellow and so on. Note: they are made from Acetal (Delrin) plastic, which isn't very resistant to acids. With Krytox to seal the joint, it shouldn't be a problem. As your glassware heats and cools, the joints can pull apart, so the clips are a good idea, this way, you don't have to use a lot of tension on your clamps to hold everything together, which allows the apparatus to expand and contract without breakage,

 

[924T]

Howdy, Irons!

The more I learn, the more questions seem to pop up!

It hit me that my 800 GPH submersible pump might be too much for an Allihn condenser, plus the fittings
would need to be adapted, so I thought I'd inquire as to what brand/model/GPH pump you use?

I researched Krytox joint grease-----didn't know it was used for scuba diving equipment, too------you
indicated a little bit goes a long way------so would a 1 0z. tube would be fitting (no pun intended, but I'll take
what I can get ) for me to start out with?

Pertaining to your Manganese Dioxide H2O2 reactor (my label for it), what kind of vessel are you performing
the Oxygen reaction in? I was thinking along the lines of a side-arm Erlenmeyer, running tubing from the
side-arm to a barbed adapter in a Claisen's 2nd port, and inputting the H2O2 through the Erlenmeyer's
main (top) opening.

Also, are you running your reflux condenser arrays outside, under a fume hood, or in a fume cupboard?

Do you electronically monitor the Nitrous Oxide that does escape from your condenser(s)?

It looks like I should have titled this thread 'How many questions can Irons bear?'.

Cheers,

Mike

 

[Lou]

So, what exactly are you trying to do?

I have Krytox 240 AC available for sale. Comes in 2 oz tubes. It's a one time application and virtually no solvent (other than fluorinated) will remove it. Works great on firearms too We use it for sealing stirrer motors shafts in bearings, glass reactor heads, injecting into grease ports blower motors, and generally anything we don't want to replace or corrode.


You will need at most a couple liters per minute, so a simple hydroponics pump or aquarium pump like at Petco would be good, and a bag of ice. Remember, the water inlet is at the bottom. Get the green keck clamps for 24/40, which is what I'd use if I were you as it's just about the most standard joint size for small-medium lab work.

The correct name for the frame work is a lattice:
http://www.capitolscientific.com/lab-supplies/lattice-supports-laboratory

Stainless is nice, but not durable in a chemical environment with refining, aluminum far less so. One can go to scrap yard and buy 3/8" titanium for $4/lb and use that and not have to worry about it. Just epoxy paint/krytox the supports that lag into the fume hood. You could powder coat the stainless and have it last, but if you move a lot around the set screws eat into the coat and then it starts...

 

[924T]

Howdy, Lou!

I'd much rather buy the Krytox from a forum member than from ebay.
Please let me know what your price is, and whether you can send me a Paypal 1nvoice for it?

What I'm getting ready to do is mount a Claisen adaptor to an Erlenmeyer (all 24/40 joints),
and then mount a 400mm bulb condenser to the Claisen, and boil some MLCC's in HCl to
get the base metals out.

Samuel-a runs the HCl boiling process for MLCC's for 2 to 2.5 hours; I'll be following his lead on that, and will be
doing this in a residential neighborhood, outside, and will use the condenser to minimize HCl evaporation loss, and
to also minimize fumes that will annoy/alarm the neighbors.

I would not have thought of using Krytox to fume-proof fume hood metal brackets! Is that common knowledge, or
an innovation of yours?

Also, never having used Krytox, it's really good to hear that it's basically a one-time application-----I honestly didn't
know if it would have to be periodically reapplied, or not.

Some delays have popped up on this end, so I'm not going to be able to perform the HCl boiling process
for about another 3 weeks. In the meantime, I'm trying to make sure I have all the right glassware and
safety equipment on hand to do this properly.

Cheers,

Mike