Amy Winehouse
Harmless
Posts: 44
Registered: 4-10-2011
Member Is Offline
Mood: Saucy
|
|
Fractional Distillation takes too long
>
Feel free to flame me for being ignorant
But on the real, is there any way to make this go faster? I tried to turn up the heat juice(tech. term) on my hotplate while distilling the legal cap
(75.5%) of OTC ethanol in CA to the azeotrope and, as the theory suggests, i got like 87% using a vigreux column. I am now watching it drip 1 drop/2
seconds and falling asleep. I'm slowly dying and I have to wait for this rubbish (not from England just like the word). There's gotta be a better
way...Use two or three columns?
This thread is about possibilities don't hate on it's dissimilarity to reality.
"I'm too drunk to taste this chicken"
-Colonel Sanders
|
|
Endimion17
International Hazard
Posts: 1468
Registered: 17-7-2011
Location: shores of a solar sea
Member Is Offline
Mood: speeding through time at the rate of 1 second per second
|
|
No, that's pretty much the optimal speed for laboratory distillations.
|
|
bbartlog
International Hazard
Posts: 1139
Registered: 27-8-2009
Location: Unmoored in time
Member Is Offline
Mood: No Mood
|
|
A bigger (wider, that is, not taller...) column will speed things up some; more volume and surface area. But in general, yes: fractional distillation
is slow. Although it is not really wise to leave distillations unattended I have sometimes done so, just because I didn't want to stand around for
four hours. Best I guess would be if you have something else to entertain you (other lab work, book, ipod...) while you keep one eye on your still.
The less you bet, the more you lose when you win.
|
|
watson.fawkes
International Hazard
Posts: 2793
Registered: 16-8-2008
Member Is Offline
Mood: No Mood
|
|
Learn the concept of a theoretical plate in the analysis of fractional distillation. That Wikipedia link will get you started, but that article is only an overview.
There's a trade-off between the number of theoretical plates in your column, take-off rate, and product separation. By heating faster, you've traded
take-off rate for separation. If you want to have a higher take-off rate with the separation you're getting now, you need a better column.
|
|
BromicAcid
International Hazard
Posts: 3246
Registered: 13-7-2003
Location: Wisconsin
Member Is Offline
Mood: Rock n' Roll
|
|
As bbartlog said a wider column will allow more throughput and allow for a faster takeoff while still returning at a fairly decent rate. Also a
taller column will allow for a faster takeoff because you are putting more theoretical plates in place however you can not take off so much that you
are not returning anything and a tall thin column is not better than a short fat column in my opinion because you risk flooding.
Different packings will also affect your takeoff rate. A Vigreux column is obviously not doing it for you in one pass, invest in a packed column,
you'll be able to achieve the same takeoff but you'll be able to get your desired proof in one pass.
Although not theoretically sound I have used a packed column without a fractional head in instances where a Vigreux with a fractional head was not
enough and been able to get my desired product with total takeoff (I.e., no return) though that's not proper technique.
|
|
turd
National Hazard
Posts: 800
Registered: 5-3-2006
Member Is Offline
Mood: No Mood
|
|
If you're impatient, your best bet is to switch hobby to something with a higher instant-gratification potential. Chemistry needs patience and amateur
chemistry in a chemophobic society even more so.
Alternative: Synthesize some Ritalin or (meth)amphetamine. Two birds with one stone!
|
|
simba
Hazard to Others
Posts: 175
Registered: 20-5-2011
Member Is Offline
Mood: No Mood
|
|
Just set it up and watch some tv. I know this is kinda difficult for a beginner, you feel like you've got a bomb planted in your house, you just can't
sit back and wait whole process, but you will eventually get used to it.
|
|