Sciencemadness Discussion Board
Not logged in [Login ]
Go To Bottom

Printable Version  
 Pages:  1  2
Author: Subject: Ethyl bromide synthesis not working
draculic acid69
International Hazard
*****




Posts: 1371
Registered: 2-8-2018
Member Is Offline


[*] posted on 7-10-2020 at 06:29


Quote: Originally posted by happyfooddance  
This is just a heating issue... There is no way you will get anything to distill over when you are only operating the bath 1.5° over the boiling point of your compound, especially when your mixture has other higher boiling substances in it also. Think about it: could you ever distill water out of an oil bath operating at 101.5°?And you especially couldn't distill water out of, say propylene glycol, at 101.5°. The boiling point of a mixture is not often equal to the boiling point of the lowest boiling compound in a mixture.

I guess you are reading the wrong way into "distill at the lowest temperature at which the ethyl bromide distills over..." A big hint: if your ethyl bromide isn't distilling over, it isn't hot enough.

I have done this only once, but it worked like a charm, I got just a bit below advertised yields, but that might have been because I was using acid that was about 8% weaker than I had thought (only titrated it after the fact). I used KBr, at about half the scale you did (and I thought I was foolhardy for trying a first time reaction on a mol scale...). I don't know exactly what I ran the bath at, but I know I had to raise it towards the end and more ethyl bromide came over, and that I stopped it when the stillhead temp started rising sharply and reached about 50°.


When testing a new mantle I plugged it in but turned the temperature down to zero
And waited to see how hot it got(this is a mantle with a 2000w 220v own motor speed controller in it as the board was fried.they let a bit of power thru even when turned down to zero) anyway a thermometer was inserted between the mantle fabric and a
1litre flask 1/3 full of water. 1hr later The thermometer was sitting at about 140'c.the water was boiling. I was surprised.
View user's profile View All Posts By User
 Pages:  1  2

  Go To Top