UKBEE (Newbee)
02-12-02 15:30
No 268571
      Fluidised sanbaths  Bookmark   

ne one tried using something simalry to this ?

sound pretty cool . saves all the nasty hot oil mess.

WB20:  Tecam SBS-2 Fluidised Sand Bath

Fast heat-ups and accurate temperature control to 350C
Safer operation than oil baths

Dry, inert, nontoxic aluminium oxide ensures hazard-free operation

Use these fluidised sand baths for your heat treating processes, temperature sensor calibrations and more. Baths use aluminium oxide fluidised by low-pressure air as a dry bath medium with excellent heat transfer properties.

Safe to use aluminium oxide is nonflammable and will not corrode your sample vessels or produce toxic fumes. Vessels of all shapes can be easily immersed and safely removed from bath, without the hazard and mess of hot oils.

An energy regulator cycles heaters immersed in the fluidisation medium to control temperature. If fluidisation is lost due to air supply failure, a built-in pressure switch automatically shuts heaters off, preventing burnout.

Make temperature adjustments via a control knob and reference dial. Achieve bath control and uniformity of 0.5C under stable conditions.

These baths require a dry air flow a approximately 3 cu ft/minute at about 3 psi pressure.

Temperature range: 50 to 350C, Optimum uniformity: 0.5C, 0.9F

Heaters: 1 x 750W,  Weight: 24.9kg

Heat up times- To 200C: 12 mins, To 350C: 26 mins

Working area (h x diameter): 3 x 6 inches

Overall dimensions (h x diameter): 12 x 9 inches

I love the smell of Ketone in the morning.
(Chief Bee)
02-12-02 16:39
No 268597
      Re: Fluidised sanbaths  Bookmark   

What does such a thing cost? It also seems to require a supply of pressurized air to make the alumina "fluid"...

Oil baths are not a problem at all if you use polyethyleneglycol 400 (cheap) as the oil. It does not smoke or smell even at temps beyond 200 C, and it is water-soluble, so cleaning the flasks is a breeze, just rinse with water.
(Old P2P Cook)
02-12-02 20:25
No 268673
      Re: Fluidised sanbaths  Bookmark   

ne one tried using something simalry to this ?

sound pretty cool . saves all the nasty hot oil mess.

If you want to avoid the hot oil mess when heating an rb flask then the standard technique would be to use a heating mantle. Fluidized sand baths are typically used for irregularly shaped objects. The surface area of the sand bath needs to be significantly larger than the cross section of the item that is being heated, a fluidized sand bath for even a 1L flask would be large and cumbersome; a heating mantle would be much more convenient.
02-13-02 10:39
No 269013
      Re: Fluidised sanbaths  Bookmark   

Cheers terbium... thats cvleared that up then...mantle it is..

I love the smell of Ketone in the morning.
(Hive Bee)
02-14-02 16:59
No 269666
      Re: Fluidised sanbaths  Bookmark   

mantles are expensive and you need a different one for each size flask and they don't stir.

to hell the fluid, i used to use a cheapo aluminum camping frying pan filled with silica sand, set on a hotplate. nestle the flask into the sand about an 2.5cm (don't touch bottom!),works dynamite, didn't cost anything and it doesn't stink and it fits every flask i used to own., party on wayne.wink

btw - if you can afford em mantles are more efficient and give more uniform heat distribution, but not all bees can afford em.

(Old P2P Cook)
02-14-02 18:51
No 269697
      Re: Fluidised sanbaths  Bookmark   

and they don't stir.
I never had this problem. You must need a new magnetic stirrer or stirring bars.
(Hive Addict)
11-18-02 16:02
No 380691
      neato  Bookmark   

this helps SWIM a lot...SWIM's bee-n pondering this bath issue...safflower oil goes the highest (that SWIM's found...peanut oil has a lower bp than safflower) aroun 220 deg. celcius before smoking, however, that's not high enough for atm distillation of isosafrole...

Polyethyleneglycol 400 sounds the way to go (a clear water soluble liquid...doesn't get much better), but it's a chem. supplier route...not OTC...not that SWIM has problems with that, but it's the cost SWIM's trying to lower at this time.

Dr sister's method of silica sand (playbox sand?) is cheap...but how many other bees have had success with this method? hey sister...can it get hot (i.e. 250 deg. celcius) with no issues? Any problems SWIS has had with that method?

It tastes like burning!shockedtongue                              
(Title on BackOrder)
11-18-02 21:57
No 380834
      dry sand and oil  Bookmark   

would it be possible to mix up a paste of safflower or mineral oil and sand to use for a sandbath, or would normal sand contain too much water for this to be safe?  A few ounces of oil added to a sandbath would greatly increase the rate of heat transfer along the sand, yet hopefully keep it from being as much of a hazard as an oil bath. 

I would only consider doing this with very large distillations, say for instance if one wanted to steam distill a 10 gallon tank full of root bark or something similar.

If at first you don't succeed, try, try again. Then give up. There's no use being a fool about it.
(Hive Bee)
11-19-02 19:16
No 381254
      PEG's  Bookmark   

A sand oil slurry would just be messy. You'd end up with a layer of oil above a bunch of oil wet sand.

High weight PEG's can be obtained from wood working supply co.'s. people melt it and soak green wood in it to stabilize it for green wood woodworking so the wood doesn't check. It infiltrates the porous structure of the wood and solidifies.

At least now you have an excuse to tell the chem suppliers.
(Hive Addict)
11-20-02 15:50
No 381585
      never done that...however  Bookmark   

even though SWIM's never tried that, SWIM'd have to agree with racemic on that one...if one were steam distilling, couldn't it bee done under vacuum? then there wouldn't bee much heating required.

It tastes like burning!shockedtongue