Sciencemadness Discussion Board

Separation Funnel as Addition Funnel

Abromination - 25-8-2018 at 14:45

Short and simple question: can I use a separation funnel as an addition funnel? I have a separation funnel but need an addition funnel and cant afford one. The reaction is open to the air (via double necked flask and is not under vacuum.

j_sum1 - 25-8-2018 at 15:16

Should not be a problem. It is commonly done. The only issues are when you have a closed system and need pressure equalisation or when you need to protect your reagents from the air.

DraconicAcid - 25-8-2018 at 15:21

I'd done that several times. Works nicely, as long as you don't need to work under nitrogen.

Abromination - 25-8-2018 at 15:34

Thanks, I dont plan on working under vacuum that often.

JJay - 25-8-2018 at 22:16

The major advantage of doing additions with a jointed sep funnel instead of an addition funnel is that you can keep adding stuff to the funnel while your reaction or distillation is running. It's nice to have a pressure equalizing funnel for running reactions that require extremely dry conditions or inert gas, and you also don't have to monitor the reaction as closely at the end of an addition with a pressure equalized funnel.

I use my non-equalized funnel more often than my equalized funnel, but they both get used a lot.



[Edited on 26-8-2018 by JJay]

arkoma - 26-8-2018 at 15:02

Actually the price of Chinese glass is very reasonable, shipping takes about ten days which is not instant gratification, but makes my purchases affordable. I have both sep and addition, in 250ml size, and have MAYBE $25US in both.

TheMrbunGee - 27-8-2018 at 09:41

I did this while waiting for real thing. It is actually amazing how much you can improvise.

PEAF.jpeg - 212kB