Alrightie, since I posted a poll that actually works, and people said they wanted pictures from the lab, here is a picture from the lab. This is probably not exciting for the other chemists out there. Does anyone get through undergrad chemistry labs without using one of these? (Scaled down a little, I imagine?)
I am amazed at the size of this thing. I mean, there are a few EPA-approved methods that involve extracting pesticides out of water with lots and lots of methylene chloride. Where I worked as an extraction lackey, we used 2-liter sep funnels. It was a bit awkward at first, but after a while the weight felt almost natural, and I only forgot to vent once.

My question: has anyone ever used one this size? or larger?

[For the uninitiated, a separatory funnel is the lovely invention pictured above. You put two immiscible solvents in (usually water + something organic) along with whatever you're looking to extract out. Be sure that the stopcock is closed first, or misery will surely ensue. Stick a stopper in the top (at left, the open-looking end), then while holding the stopper on you quickly flip it stopcock-up and open the stopcock to vent. Then, close the stopcock, shake briefly, vent again. Repeat until there is no hissing when you vent. Then shake the hell out of it. Once you flip it rightside-up, the layers separate (if you are lucky) and you can drain one of the solvents off.]


mitch said...

Next time maybe you could put something next to it, so we can get a sense of scale. :)


jokerine said...

Ive used 1 liter. Like the text color.


een of andere vent said...

I have been on a lab where we had one. It was sometimes used to extract the waterbath of a rotavap when some spastic student dropped his round-bottom flask in it.

Ψ*Ψ said...

ouch! glad I've never dropped anything important into the water bath. (well, never anything at all, really)

BaggieBoy said...

Where I work, it is frowned upon to use a sep funnel bigger than 2l. Instead we use fixed separators, liquid is introduced using vacuum and mixing of the phases is carried out using an overhead mechanical stirrer. This si much easier and safer than trying to manhandle large amounts of liquid, remember 1l of DCM weighs 1.3kg.
I can provide a picture of one of these if that would be useful

Bill said...

I saw one at P&G once that was 25 lts, in their pilot plant. It looked more like a small cement mixer. =)

Lunch is Served! said...

I'm sorry, I won't be able to lift the loaded sep funnel up in my puny arms :(