Fyndium
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Paraffin heating bath heat source?
I'm currently using induction plate as heater, but I'm worried if the plate can handle +200C temp vessel on top of it. I would want to avoid open
flames as hazard. Are there any other means to heat it or should the induction plate handle it? Could it be insulated with something like ceramic
fiber mat?
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macckone
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a thin ceramic fiber mat may help.
Some induction heaters don't work well unless the pot is in direct contact with the plate.
What is the plate actually made of?
Also most of the induction plates that I have seen have a built in temperature sensor so they will shut off above some temperature and cycle.
adding a fiber mat will prevent the plate from sensing the temperature accurately, which may or may not be a problem.
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Fyndium
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I got some candles lying around that were "paraffin and vegetable wax" and I melted them and the melt started to smoke already at 150C. Candles don't
seem like a good source for paraffin.
Artisan shops do sell pure paraffin granules for 5 euros per kg so it's not that bad.
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macckone
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paraffin for candles is horrible for heating. It is intended to light at a low temperature.
Temperatures much above 200C are poorly suited for organic liquids.
potassium and sodium nitrate mixture melts around 220C.
sodium carbonate and sodium hydroxide mix melts around 240C.
But these molten salts have large heats of fusion.
You are really better off with sand or metal shot.
copper coated steel bbs are great and readily available.
despite its density steel has a relatively low specific heat.
aluminum pellets are easily available and have high conductivity and also have lower specific heat than sand.
aluminum has the draw back that it oxidizes and the oxide will scratch glass.
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Fyndium
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Liquid paraffin sold for wood treatment, skin, laxative etc is not that bad for lower temps, I tested it out at other thread and it effectively starts
to emit a little smoke at 160-170C, but might dissipate eventually similar to silicone oil which took a couple of hours to settle. It has fancy smell,
though.
Steel shots seem to be available in bulk for shotguns, starting from 1/10" or 2.54mm about 5 euro per kg. They are available as plain, zinc or copper
coated. They should be quite suitable for the purpose?
Should the flask be immersed with the shots, or can it just be lowered in a "pit" formed from them in order to be able to easily control heating by
raising or lowering the equipment?
Btw, the induction heater surface is probably from tempered glass, few mm thick. Or borosilicate. Can't say other certain but glass.
[Edited on 13-9-2020 by Fyndium]
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macckone
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Copper coated steel shot is pretty good.
How much of a hole you want is going to depend on the reaction.
You can either pour the shot around the flask or lower the flask if you can deal with a lower contact area.
Since you are using an induction heater, you may get high frequency vibration from the shot.
I am not sure how deep the shot would need to be since I have never used shot with an induction heater.
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