RogueRose
International Hazard
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Strange behavior (temp drop when more heat is added) during distillation
When I am running a distillation of ethanol and putting 1 kw through it, the temp during the end of the run may be 200F and if I use a 1500w heatgun
to heat the outside of the container, the temp right before the condenser drops drops about .1-.2 degree every second and dropped 4-5 degrees after
20-30 seconds.
Is this normal? Why does this happen?
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Marvin
National Hazard
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You've not described your set-up, but if you are fractionating there can be a delay before the next fraction hits and it's the lack of vapour that can
make it look like the temperature is dropping.
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RogueRose
International Hazard
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Quote: Originally posted by Marvin  | | You've not described your set-up, but if you are fractionating there can be a delay before the next fraction hits and it's the lack of vapour that can
make it look like the temperature is dropping. |
Simple pot still with a 2' vertical to a T (that is where the temp is taken) a short 4" connector to a T to a long condenser going down. The column
is copper.
Also in ethanol distillation what happens if "too much" heat is used (if the purpose is to just "strip" a mix that has a low alcohol % - so it is just
a fast stripping run. can too much heat be used?
[Edited on 22-7-2016 by RogueRose]
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Magpie
lab constructor
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Mood: Chemistry: the subtle science.
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I agree with Marvin that you are not getting any vapor to the bulb. the pot residue is not sufficiently volatile for the heat delivered.
The single most important condition for a successful synthesis is good mixing - Nicodem
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