Sciencemadness Discussion Board

help identify this enormous dean-stark trap

edgecase - 2-7-2012 at 16:17

Not sure if the photo shows it, but the inner tube has a funnel on the top, and is open on the bottom. It looks like it will cause mixing or help complete the phase separation. I'm thinking it's more for synthesis to remove water than for analytical use, being so large, it's about 800mm tall.

giant_dean_stark_trap.jpg - 34kB

ScienceHideout - 2-7-2012 at 16:59

Isn't that the one that they use in azeotropic distillations? It seems sorta similar to this:

http://www.chemglass.com/product_view.asp?pnr=CG-1266

edgecase - 2-7-2012 at 18:20

Quote: Originally posted by ScienceHideout  
Isn't that the one that they use in azeotropic distillations? It seems sorta similar to this:

http://www.chemglass.com/product_view.asp?pnr=CG-1266


Perhaps, but the tube doesn't return the "heavy" solvent to the boiling flask, but rather catches the reflux condensate, and directs it to the outlet at the very bottom of the trap.

Aside: that is a very nice looking heavy solvent trap, I have one but it doesn't have a drain like that; only the light solvent ones seem to have drains.

Magpie - 2-7-2012 at 18:24

That may be a "lighter than water" liquid-liquid extractor.

The less dense solvent drips from a condenser into the funnel. It then builds a liquid column in the funnel until sufficient head exists to drive it out the bottom of the funnel. It then floats to the top, extracting solute from the more dense solvent along the way. It then overflows back into a pot (RBF) through the sidearm. Here the solvent is re-evaporated back into the condenser leaving the solute to accumulate in the pot.

Are those disks that center the funnel stem by any chance perforated?

edgecase - 2-7-2012 at 18:40

Quote: Originally posted by Magpie  

Are those disks that center the funnel stem by any chance perforated?


No, but I'm guessing that would be an improvement; by causing the droplets to be broken up into smaller droplets as they rise. As it is, this one just has the solid discs.

I think you've figured it out though... the need to build up head pressure would explain why the tube part above the liquid level is so tall. Cheers.