Sciencemadness Discussion Board

Heating mantle smoking

DocX - 14-7-2022 at 04:15

I bought a new heating mantle and used it the first time today. It has been standing for quite some time in the garage, but has never been used before.
Today I fired it up for a distillation test run. It started giving off a thick, white, smelly smoke. Still worked, and heated up very well, but the fibrous coating started turning brown and smoked like a chimney.
Naturally I aborted the distillation and put it outside to fume off.

Is this normal when you use a new heating mantle? Does it need to fume off residues in the coating? Should I just continue heating it until it has fumed off?


[Edited on 20222222/7/14 by DocX]

DocX - 14-7-2022 at 05:43

Like so

F67626DD-7D7E-476B-9835-E5844241DB6B.jpeg - 5.1MB

DocX - 14-7-2022 at 11:59

I was a little hasty posting this. I found the answer not by UTFSE but by UAFSE (Using ANOTHER F***ing Search Engine. Funny that the best way to find posts on this forum is through Google …).
Apparently heating mantles often ship with a coating that needs to be burned off before use. I ran it full heat for 1 hour and the mantle part turned black, then partly almost silvery white. No smoke anymore, but still some smell.

DocX - 14-7-2022 at 12:48

Like so

C2E93AB6-0C55-4A05-97B3-2854EB1F9701.jpeg - 454kB

BromicAcid - 14-7-2022 at 13:36

Yes, heating mantles do smoke, even if they have been in use for awhile. Obviously if you spill something in them that can be the culprit. A bad fitting heating mantle can also cause some smoking issues because you have to put too much heat into it and can eventually fuse the glass. Not to take anything for granted but what are you using for a voltage regulator, sure hope you're not main-lining this. Anyway, run it for awhile, try to always have something in the mantle to act as a heat sink unless you're at low voltage and then put it in service. Just resist the urge to go full power (warp speed) and it should be fine.

Texium - 14-7-2022 at 15:08

Quote: Originally posted by BromicAcid  
Not to take anything for granted but what are you using for a voltage regulator, sure hope you're not main-lining this.
From the pictures, it appears that it has a built-in knob to control the voltage. Might still be better to run it off a good variac though. I wouldn't trust these cheap electronics to accurately limit the voltage.

Sulaiman - 14-7-2022 at 17:59

Both my new-parts diy 500ml mantle,
and a 5l mantle stored for some time,
gave an alarming ammount of smoke when first used.
Now negligible smoke unless spills or dust get on the elements/baskets.
Variacs are nice when you have them,
but very expensive (compared even to a pid controller with ssr)
A well rated 'dimmer' controller is a very useful and fairly safe option.
(eg for a 110V 550W mantle you need at least a 5A controller, so buy a 20A or even 50A controller. (check prices vs various options)
The inbuilt temperature controller will be ok for simple distillation/refluxing if it is the on/off thermo-mechanical type,
Ok for fractional distillation if of the 'dimmer' type (phase-angle control) or better.

greenlight - 15-7-2022 at 10:07

Had the same experience with a new chinese heating mantle. Was seriously worried there was a wiring problem in the lining.

The white smoke went away after 40 minutes or so and hasn't done it again.

DocX - 15-7-2022 at 13:47

It has now been used in several distillations and the smoke is definitely gone. It has, as someone spotted, a built-in voltage regulator (and stirring). It wasn’t very expensive, but not dirt cheap either. But it’s Chinese, and I always take everything I buy from China that runs on >50V apart and take a look under the hood. It seems well built enough. And works like a charm. Very good temperature control, good resolution on the heat knob. I am a happy little chemist.