Sciencemadness Discussion Board - Seporatory funnel, please advise

Seporatory funnel, please advise

Pyro - 28-4-2012 at 14:30

hi,
i'm about to buy my first seporatory funnel, and i'm stuck between 500 ml and 1000ml, a 1000 ml one is 15 dollars more, but i suppose it can't be to big but can be too small, right?
and another thing, they look pretty delicate, can i put them in the dishwasher?
thanks for the help,
pyro

bbartlog - 28-4-2012 at 14:45

I don't see how a dishwasher would reliably get one clean. The opening is too small.
Unless you have a specific reason to think that you will be working with bigger volumes, I'd go with the smaller separatory funnel. Aside from the cost, the larger one may be unwieldy.

Pyro - 28-4-2012 at 14:52

true, but does it make a big difference if its a bit too big?
that's a good point, as it already has a bit of a hard time drying Erlenmeyers, but the actual process will not break it?

Vargouille - 28-4-2012 at 15:43

It shouldn't break it, considering the thickness of the glass.

EDIT: Not that I would recommend putting them in the dishwasher, mind you.

EDIT 2: The water shouldn't affect the glass, but it might play havoc with the stopcock.
[Edited on 28-4-2012 by Vargouille]

[Edited on 28-4-2012 by Vargouille]

Pyro - 28-4-2012 at 15:48

ok, thanks, ill see if its possible to remove it.
but what about the size?

Geko127 - 28-4-2012 at 16:05

Hell... Why not buy both.

Funkerman23 - 28-4-2012 at 16:26

Which size you want really depends on what you want to do. You can always use a larger funnel for smaller amounts but even with a smaller funnel you can still do what needs to be done. My gut says go with the larger one if only to allow room to grow. as for dishwasher use I have to say one thing: DO NOT USE A DISHWASHER THAT IS USED FOR LAB DUTY TO WASH EATING UTENSILS. that warning aside I hand wash my glass. it allows me to both wash and inspect each piece before I put it back on the shelf.

Pyro - 28-4-2012 at 16:34

ok, so the 1000 ml one it is.
as for the dishwasher, we obviously only have one dishwasher, and we do use it for both, but i never just put em in, i wash them out with soap and water, and put them in to get them completely free of anything i could have possibly missed and to get the nice shiny clean look. this comes from my days at school, when all the beakers and flasks had thick rings of calk on them. it gave me the tattars.

Pyro - 28-4-2012 at 18:05

Quote: Originally posted by Geko127

Hell... Why not buy both.

cos hey cost 60 and 75 dollars!

Funkerman23 - 28-4-2012 at 20:01

Quote: Originally posted by Pyro

ok, so the 1000 ml one it is.
as for the dishwasher, we obviously only have one dishwasher, and we do use it for both, but i never just put em in, i wash them out with soap and water, and put them in to get them completely free of anything i could have possibly missed and to get the nice shiny clean look. this comes from my days at school, when all the beakers and flasks had thick rings of calk on them. it gave me the tattars.

True true( my school was worse..a good number of start cracks where to be had and they didn't think that was a problem) but it is an old habit I learned from my mentor. I keep as much of my lab equipment away from the main house as possible and I'll admit I'm a miser on safety.

[Edited on 29-4-2012 by Funkerman23]

Pyro - 29-4-2012 at 02:51

i work in the kitchen under the extractor fan with a big board of wood with a rim around it on the stove, and cover the rest with newspaper or plastic, obviously for things that involve explosions (making sodium for example) and things that involve very poisonous things i go outside.
its a bit of a contradiction, there glassware is dirty, cracked,... and they don't worry about that, but a few yrs ago they made us give them a buck to burrow a lab coat to light a Bunsen burner, OOOO dangerous! *sarcastic*

Hexavalent - 29-4-2012 at 04:23

Not necessarily, it depends on what material your street clothing was made of. If it were a synthetic fabric or fiber, it could potentially pose a serious fire risk, as well as melting and sticking to your skin horribly.

Pyro - 29-4-2012 at 05:03

i suppose,
the flame was about like a candle flame :p i always wear 100% cotton shirts, so no problem for me, but i get your point.
but a buck! i just ordered a few new lab coats online with one of my glass orders :p never more do i pay a buck for an oversized dirty labcoat.
back on topic:can i use a universial clamp to hold it? or do i need a special holder?

Funkerman23 - 29-4-2012 at 09:32

Quote: Originally posted by Pyro

i suppose,
the flame was about like a candle flame :p i always wear 100% cotton shirts, so no problem for me, but i get your point.
but a buck! i just ordered a few new lab coats online with one of my glass orders :p never more do i pay a buck for an oversized dirty labcoat.
back on topic:can i use a universial clamp to hold it? or do i need a special holder?

Noting special is needed for a seperatory funnel if you don't have a ring support a simple 2 or 3 prong clamp suffices.

Magpie - 29-4-2012 at 09:40

A ring of the proper size with split rubber hose pieces so not to damage the glass is very nice.

I would buy the 500mL sep funnel myself. I've never needed one bigger than that. A bigger one would just take up more storage space and not give as clean a separation for small amounts. Losses on the wall will be greater, and it costs more too. There's a reason they make them in the smaller sizes.

Pyro - 29-4-2012 at 11:56

ok, i suppose if i have more than 500 ml to do i just do 2 batches

Magpie - 29-4-2012 at 17:54

I recently bought a 10cm iron ring for my 500mL separatory funnel. Tonight I added 3 pieces of rubber hose secured in place with black electrician's tape. As you can see this makes a nice support.

Geko127 - 30-4-2012 at 00:45

Yep. Thats good advice. Get a 500ml & a 1ltr. They both serve there purpose. The 1ltr would be better of the two. And why the hell would you put a sep funnel in a dishwasher ?. Oxy wash nappy soak works well cleaning glassware

Quote: Originally posted by Pyro

Quote: Originally posted by Geko127

Hell... Why not buy both.

cos hey cost 60 and 75 dollars!

Pyro - 30-4-2012 at 03:34

ok,
first ill get the 1 litre one, and when i can afford it ill buy a 500ml one, but can someone say what a reasonable price is for a 1l and 500 ml sep funnel?
and what is:''Oxy wash nappy soak works well cleaning glassware''?
thanks

Funkerman23 - 30-4-2012 at 06:58

Quote: Originally posted by Pyro

ok,
first ill get the 1 litre one, and when i can afford it ill buy a 500ml one, but can someone say what a reasonable price is for a 1l and 500 ml sep funnel?
and what is:''Oxy wash nappy soak works well cleaning glassware''?
thanks

You might have a good bit of luck with Laboy (http://www.laboyglass.com/index.asp) the glass is actually decent and they have plenty of options. You may have to deal with the broken English descriptions but they are worth it. And they sell to individuals, unlike Chemglass , or Kontes.

Pyro - 30-4-2012 at 08:29

looks good, and less expensive :p
how about the:'' Oxy wash nappy soak''? what on earth is that?

Fyndium - 10-3-2021 at 00:34

I've faced most often the issue of too small separatory funnel. If the volume is 1L, the useable volume is starting from 500mL for effective shaking, which means it can handle about 250mL of treated substance at a time. For mere layer separation this does not apply.

Btw, are there some designated uses for different shapes of separatory funnels:

- Cylindrical
- Pear shape
- Globe shape

draculic acid69 - 10-3-2021 at 02:26

Hell no with the dishwasher. And with SEP funnels bigger is better.
I have a 250ml one and one time I had a liter or two to seperate.
What would have taken one afternoon with a bigger funnel now
Took a few days of splitting this liquid into small enough batches
to seperate in the funnel.never get caught out with having a too small
SEP funnel if U can avoid it

Sulaiman - 10-3-2021 at 03:17

I have not bought a sep. funnel yet
but if I do I would get one with ground joints top and bottom -
for a little more interoperability with my existing glassware.