idk
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Anti-bumping surfactants in destructive distillation
I've seen a video of the process where a surfactant was added to prevent bumping which tbh was a completely new information for me.
An author of the video didn't mention what kind of surfactant it was except the fact it was used in photography. He also mentioned he had to use much
more than he expected.
I am not interested in the particular rxn he performed but rather how the surfactant should be chosen.
According to the vid. he distilled sodium-hydrocarbon sulfate with sodium nitrite. AFAIK there are anionic, cationic, amphoteric and non-ionic
surfactants .
I am guessing anionic surfactant as SDS would work, but I have no clue why I think so. I also assume non-ionic surfactant would work here as well. Am
I right, why/ why not?
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DavidJR
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The surfactants used as wetting agents in photographic chemicals are usually non-ionic. Triton X 100 is common.
Also, if you do use a surfactant then be sure to add very small amounts of dilute solutions. The pure surfactant chemicals are very potent and trust
me, you do not want to add too much. (Imagine the worst foaming mess ever)
[Edited on 4-9-2018 by DavidJR]
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idk
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Thanks. I worked with mostly SDS and CTAB and I know they have extremely low CMC.
After consideration I think anionic surfactant could not be used as it would react and form 1-nitrododecane (in SDS case as it's the cheapest), and
cationic ones would react too.
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UrAverageHobbyist
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Quote: Originally posted by idk  | I've seen a video of the process where a surfactant was added to prevent bumping which tbh was a completely new information for me.
An author of the video didn't mention what kind of surfactant it was except the fact it was used in photography. He also mentioned he had to use much
more than he expected.
I am not interested in the particular rxn he performed but rather how the surfactant should be chosen.
According to the vid. he distilled sodium-hydrocarbon sulfate with sodium nitrite. AFAIK there are anionic, cationic, amphoteric and non-ionic
surfactants .
I am guessing anionic surfactant as SDS would work, but I have no clue why I think so. I also assume non-ionic surfactant would work here as well. Am
I right, why/ why not? |
Sodium hydrocarbon sulfate comon lmfao.... Its called sodium ethyl sulfate. And the surfactant u are looking for called dimethichone (Aka silcone
oil). This can be found OTC inn the form of silicone grease witch is a mix of silicone oil and amorpheous silicone dioxide as a inert thickerning
agent. This silicone grease also works wonders for ur ground glass joints.
[Edited on 8-9-2018 by UrAverageHobbyist]
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DrP
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Granules, sticks and slow controlled raising of heat to the acquired temps. Some distillations are just awkward and you have to be patient.
I used to have trouble distilling a particular monomer which kept bumping... I had to use a small column before the condenser as a spacer to allow
for the fact that it was going to bump up. The column stopped the liquid from bubbling over into the collector - it would go back down the column and
only the vapour would go across (with some practice). It just puts some extra physical space in the set up to allow for bumping. If it does bump then
won't ruin the distillation as it wont go across.
Never heard of the surfactant usage for anti bumping... I've never really understood how a surfactant pops bubbles when most soapy surfactant type
materials help with bubble stability. We use anti foaming surfactants... they are so similar chemically to other surfactants and are very soapy...
so I don't understand how they work.
.....looking it up they must be insoluble in the foaming media but still very surface active. They spread across the surface of the bubble like any
surfactant would but pop it because they are insoluble and interfere with the film.
\"It\'s a man\'s obligation to stick his boneration in a women\'s separation; this sort of penetration will increase the population of the younger
generation\" - Eric Cartman
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Vinylogous
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Why don't you ask CaptainMolo? Pretty sure he is the author of the video you speak of.
Edit: I got you, mate
5-10% Triton X 100
25-30% propylene glycol
The difference is water.
[Edited on 13-9-2018 by Vinylogous]
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macckone
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Brewing supply places often sell various anti-foaming agents for distillation. Obviously these are intended for mash but they work really well for
other things.
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