Sciencemadness Discussion Board

Insulation affects yield in distillation?

CHRIS25 - 10-8-2014 at 04:52

Please could someone answer the following:

I experimented during the water/steam distillation of Orange oil. After a couple of hours I removed the well wrapped foil from around the tall still head and glass curve, and the neck of the biomass flask. At this point there were tiny miniscule droplets of oil mixed with water running down the condenser. 15/20 minutes after the foil insulation had been removed there suddenly appeared a mass of much larger globules of oil with absolutely no visible water pouring down the condenser.
I was surprised, but would I now be right in assuming that the oil vapour carried up in the steam has a higher temperature and as a result any steam not containing the oil will condense much quicker than the steam that contains the oil and as a result the oil vapour is carried further? Unfortunately I am unable to measure temperatures in this setup. Thankyou.

(The removal of the foil obviously lowered the temperature of the top right angled glass, since I could now run my fingers across it 3/4 of the way without being burned.

I still, after so many weeks, have not been able to find expected vapour temperatures that different oils, extracted from organic matter, can reach. Or maybe I am asking the wrong question here, success in extraction now is being over-shadowed by a realisation that I could increase yields if I could understand more about the kinetics of all this, many observations have led me to realise that controlling the temperature at which something is extracted affects yield percentage. But the only way I can control temp at the moment is by adjusting the amount of insulation I use; reducing the temp of the hotplate simply stops the extraction process).

[Edited on 10-8-2014 by CHRIS25]

arkoma - 10-8-2014 at 06:59

Chris--I can't provide the data ya want but this setup works well for me:



i DO keep aluminum foil wrapped around the distillation head and a good flow of ice water running through the condenser. I don't want anything condensing/lingering til it gets to the condenser. Remember too, the mix is gonna never be able to rise above 100C--here in Arizona (altitude I guess) water boils at about 98-99C.

Edit--I find a steep angle on the condenser helpful

[Edited on 8-10-2014 by arkoma]

aga - 10-8-2014 at 08:54

Wow !
Does your laptop get THAT hot ?

arkoma - 10-8-2014 at 09:01

LOL

CHRIS25 - 10-8-2014 at 09:10

Yes my thinking originally, Quote: (I don't want anything condensing/lingering til it gets to the condenser"); However it seems from the many distillations that I have done, that you get more oil when allowing some steam to condense before it reaches the condenser. I have seen how you can get a ton of water and oil droplets very fine by keeping the whole thing insulated, as opposed to not insulating where one gets very large droplets of oil and a lot lot less water. this happened also with the rosemary.

Texium - 10-8-2014 at 09:34

Quote: Originally posted by aga  
Wow !
Does your laptop get THAT hot ?
Ha, that's exactly what I was thinking when I saw that! I was going to comment on it, but I didn't.

arkoma - 10-8-2014 at 09:35

CHRIS25, I'll give it a whirl next time (no insulation)

hyfalcon - 10-8-2014 at 15:41

I see the water quality hasn't improved any since I was out there. Deposits in the water jacket of that condenser look considerable.

arkoma - 10-8-2014 at 21:19

ah yeah, its a fecking mess (my condenser's water jacket). The "business" part is clean as a whistle though--Harbor Freight sells a nice nine piece brush set for $5

arkoma - 13-8-2014 at 11:40

I have done two distillations of ground cloves. Preliminary results from equal starting weights and quantities of collected distillate indicate higher yields from the foil wrapped flask/distillation head. Extracted with ethyl acetate--the "wrapped" extract is colored significantly more. I have to locate a set of AA batteries for my camera so I can get some pics before I distill off the EtAc.

Edit--found the batteries.

More details-14gm ground cloves, 250ml water in 500ml RBF. Collected 125ml distillate from each run, then extracted with 50ml EtAc. The erlenmeyer contains the EtAc extract from the foil wrapped rig, the 250ml RBF from the bare disty head.

[Edited on 8-13-2014 by arkoma]

foil wrapped.JPG - 349kBunwrapped.JPG - 285kB

clove oil

quantime - 13-8-2014 at 15:04

I have distilled clove oil using water. It made two different oil layers. The clove oils are powerful. One drop makes my mouth go numb. It takes a few minutes before I can feel my tongue again.

Question: After the distillation are you extracting the hydrosol with a solvent? How does that work? I was just dropping the water from the receiving flask with a sep funnel after the distillation is over. I only get like 1ml or thereabouts of oils this way.

Chris: How about attach a vacuum to your condenser to lower the temperature. Do you get better yield if the temperature is lower?

I think this cheap-o pump might work

http://www.ebay.com/itm/400615363324



[Edited on 13-8-2014 by quantime]

[Edited on 13-8-2014 by quantime]

arkoma - 13-8-2014 at 15:24

I extracted the hydrosol/oil distillate with Ethyl Acetate, then used my sep funnel. The pics are the "intermediate"; havena evaped off the solvent yet. On my list of things to do today

CHRIS25 - 14-8-2014 at 05:46

@quantime - Hi, I have no clue as to how that vacuum works or what you are supposed to do with it. Ignorance here. But as I understand from various resources, a vacuum distillation highers the temperature not lowers it. Anyway I also found that many of the oils I will be extracting have degradation temperatures far higher than ever I could produce.

@Arkoma - nice to see your work here, however, despite the fact that when using insulation around the Whole apparatus the yield is 80% within the first 20 minutes, only insulating a part of the apparatus (Boil flask, still only, Not the connections from the still to the condenser) my yield is a little more EXCEPT for the fact that it takes a few hours to get that 80%, the difference being is that I get very little hydrosol, with the former insulation method I can use up quite a lot of water and therefore get a lot of hydrolsol. Also, and this is very subjective since no way could I analyse this, the quality of the oil from a slow distillation process appears/smells, subtle colour difference against strong natural light - it appears better quality. Further reading suggests that fast distillation on many organic products does lower the quality a bit. I put the two distillations side by side in natural light in test tubes, the slower distilled product was a subtly different colour and smelled slightly stronger.

Very subjective I know, but I have no other means to judge things. I suppose it is all about time, the longer it goes the more you get. I did another orange distil a few days ago and after 8 hours was still getting oil! Yes really. I am doing another one right now, I just took away the insulation from the connections between the still and the condenser (we are talking 17 inches of tubing here) and I am now getting the same amount of oil flowing down the condenser but hardly any water. So this is repeatable and does have an effect.

vacuum

quantime - 14-8-2014 at 07:44

Chris, it is the other way around. The gas law is PV=NRT. Pressure is proportional to temperature. Lower pressure means lower temperature. If you want to distill with lower temperatures I think the best move it to reduce the pressure.

From doing extractions myself, I came to the conclusion that most of the oil comes over right at the beginning. Generally there is no need to run an extraction for hours. My most successful setup was to run steam through a biomass flask.

[Edited on 14-8-2014 by quantime]

CHRIS25 - 14-8-2014 at 10:24

Oh, vacuum, ok, told you I was ignorant. Yes that is what I am doing, through a biomass flask but keeping only the biomass flask and the neck of the flask with water underneath insulated. This to ensure that as little as possible steam condenses back into the flasks. Insulating the rest just means I get more hydrosol but no increase in oil. So yes, 8 hours is overkill I know. And yes the majority of the oil appears within the first 30 minutes. But then the volume is doubled after many hours. I used to do this with orange peel in water, and 80% of the oil appeared within the first 5 minutes after full temp was reached. But I use the biomass flask now because I can fit 4 times the amount of oranges. I am 6 hours down the road now and the oil yield has actually doubled from the first hour.

aga - 15-8-2014 at 12:17

i recently did about 20 distillations.

Tinfoil helps a lot.

Remember that the heat source has to heat up a lot of air cooled glass as well as the stuff you're distilling.

With a 360mm column, a weak heat source can fail to get the glass hot enough to give any distillate at all.

You just get reflux instead

Edit : new project idea - PID rbf heater - SMantle v1 .

[Edited on 15-8-2014 by aga]

arkoma - 15-8-2014 at 13:56

Quote: Originally posted by aga  

Tinfoil helps a lot.


What I think so too, but i'm just a dumb redneck. Oh wait, I have empirical data to back that up.

edit--grammatical errors

[Edited on 8-15-2014 by arkoma]

aga - 15-8-2014 at 15:27

Hot damn !

Em-peee-ree-cale.

He gawt Day-tar, an ay ain't meanin' Daytona.

Give it up bro.
Spill doze beanz. C'mon.

Edit: further grammatical errors introduced

[Edited on 15-8-2014 by aga]