Author Topic: atmospheric isomerization  (Read 9197 times)

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Osmium

  • Guest
> When you said stir and heat to 125C and ...
« Reply #20 on: May 08, 2002, 06:09:00 PM »
> When you said stir and heat to 125C and everyone on the
> board is talking about all of these water problems.

There are no water problems. Don't make this more complicated than it really is.

> Is fractionating column necessary.  SWIM has a short
> vigreux but did not use it for safrole distillation.

It is not necessary to use one, but if you have one lying around, and if your vac is good enough so you won't lose too much it is ALWAYS advisable to use one.


I'm not fat just horizontally disproportionate.

SuperStar

  • Guest
Thanks Osmium: SWIM definetly needs a little pep ...
« Reply #21 on: May 08, 2002, 06:16:00 PM »
Thanks Osmium:

SWIM definetly needs a little pep talk, starting to get overwhelmed.

Update: Been stirring all night with reflux condensor.  Now ready to vac distill.  Oil bath has cooled to 50C.  Hooked up vac and turned on vac as low as possible. SWIM is getting a bunch of suds forming and climging the flask and still head.  Turn off vac and go away but as soon as vac is applied they start forming and climbing.  SWIM is letting oil bath continue to cool right now and try again.  Anyone seen this and have suggestion. If SWIM keeps vac on the suds will definetly climb all the way over.  BTW: SWIM's vac distills safrole at 100C, sort of strong, but can be turned down to what SWIM would believe sass comes over at 140C. The vac is on the lowest setting right now but still forming suds.

Pardon my friend officer, He's a little slow.

greeter

  • Guest
4. Release vacuum and continue to stir with heat, ...
« Reply #22 on: May 08, 2002, 07:47:00 PM »
4.  Release vacuum and continue to stir with heat, disconnect hose from vacuum source.  Go to bed or whatever

What temp do you stir it at overnight, the same temp as that used to drive off the water, or ?

Chromic

  • Guest
fractionate!
« Reply #23 on: May 08, 2002, 09:10:00 PM »
>Is fractionating column necessary.

They are not necessary but if you do not have one get one now! They are especially useful for distilling ketone. Again, it can't be said enough, GIGO. If you're not carefully separating your safrole, iso and mdp2p... you will get really terrible yields. (take my word for it)

SuperStar

  • Guest
Thanks noj and Chromic, SWIM is having a terrible ...
« Reply #24 on: May 08, 2002, 09:46:00 PM »
Thanks noj and Chromic,

SWIM is having a terrible time with this.  SWIM distilled safrol twice.  Once it came over at 90C, the next time around 100-103C.  Right now SWIM has something clear coming over at 90C. SWIM dosen't know what it is?  Vac is too strong for it to be water.  It can only be two things, safrole or isosafrole.

Right now SWIM is planning on distilling everything he has. The messed up stuff from yesterday and the shit that is coming over right now at 90C.  Then combining everything together and starting over with the iso. 

Pardon my friend officer, He's a little slow.

abacus

  • Guest
one more thing.
« Reply #25 on: May 08, 2002, 10:42:00 PM »
A couple of other points. 

1.  10% KOH is too much and a waste.  3% works fine.

2.  Greeter, my answer to your question is: My vacuum pulls safrole over at 115-120DegC, so i heat up to say 110 under full vacuum which makes sure any water present is boiled away, then release vacuum and heat at 140DegC  or so, and go to bed. 

Water has never been a problem.

It really is very simple and its a matter of choice how you like to do it.  I like doing it the way i explained beacause i only have to set up my glassware once.

Abacus

LaBTop

  • Guest
Ahumm!
« Reply #26 on: May 09, 2002, 01:06:00 AM »
See

Post 294437

(LaBTop: "Prefered next steps after freezing:", Methods Discourse)
, I have just editted it extensively so even the most fresh beginner will hopefully understand it.
It explains why and how things should be done after sassafras to safrole, freezing out and distilling proceedings.
For those proceedings, read the whole damm important thread, did we type all that stuff for nothing?
Especially read the last line in that

Post 294437

(LaBTop: "Prefered next steps after freezing:", Methods Discourse)
.

Follow proceedings outlined by me in that whole thread, and you will have no problems with your ketone, obtained through the next procedure after isosafrole: a performic or peracetic procedure. LT/

WISDOMwillWIN

pickler

  • Guest
suds and safrole
« Reply #27 on: May 09, 2002, 02:47:00 AM »
When you apply your vac to your oil, it will foam. If it's hot, it foams more. Just vary the vacuum. Start on the lowest setting and slowly increase the vacuum. If it gets out of control, then back the vac off a little. Takes a little bit to get the hang of. Or you could just let your oil cool completely down and go from there. It happens to swim all the time. Nothing to worry about. If you think it's bad with your vac you should try swim's vac. Pulls safrole at 70-72c. If your unsure what is coming over then just distill without vacuum. It's much easier for seperation of safrole and isosafrole.

We'll soon find out if I'm a chemist or not!

SuperStar

  • Guest
Thanks Pickler, SWIM is starting to get it back ...
« Reply #28 on: May 09, 2002, 03:34:00 AM »
Thanks Pickler,

SWIM is starting to get it back together again.  Glad to hear about your vac. SWIM thought he bought way too big of a pump. Right now SWIM appears to be pulling ISO at a steady 91C. The thermom has not moved in about 2 hours.  SWIM is starting to think that the suds could be from too much KOH. 1st time used 10% by weight. Don't know who said this but that is way too much, SWIM thinks somebody said use 10% if you are using undistilled safrole(oil).  2nd time tried 5% by weight.  Next time going to adjust the numbers to 2% by weight.

SWIM is thinking that so much vacuum might make distilling not as pure as doing it at higher temps? SWIM's hotplate cannot get the oil bath above 175C, so everything must come under that.

Pardon my friend officer, He's a little slow.

LaBTop

  • Guest
Ahumm,
« Reply #29 on: May 09, 2002, 04:48:00 AM »
Make that ~30°C under that 175°C of your oilbath.
The 30°C extra are "used up" in providing enough energy to let your isosafrole vapours reach the stillhead and the mouth of the watercooled condenser, where it can be condensed and start flowing to your receiver flask.
You need quite an overshoot in temperature to push concentrated boiled off vapour all the way up.
On their way up, inevidently part of the vapours will be so much cooled off by the vigreux column, that they condense on the spikes and walls of the vigreux and fall back as drops in the flask again.

The whole trick with the vigreux is simply said to play around with your temperature setting in such a way, that the first fraction, the safrole residue, which needs less energy to reach the top than the isosafrole, will come over, and the isosafrole will all the time condense and fall back while that is happening.
Your vacuum must be the same setting all the time, or your vigreux column can not do it's trick.
You only gradually increase the temperature under the same vacuum, to reach the point where the safrole starts condensing in the condenser, but the isosafrole keeps falling back from the vigreux.

Then, after no more safrole will come over at that lower temperature, you discard the contents of the receiver flask, and increase after that the heat again, and then all your isosafrole will come over at a higher temperature setting.

Did everybody forget already to put a 3-way valve between the condenser and the vacuum alonge, so you can maintain vacuum in the system while removing receiver flasks?
That way you won't have that famous foaming, caused by re-introduced AIR when you apply full vacuum on the whole system again, without a 3-way valve. And avoid oxidation/carbonization of hot oils. LT/


WISDOMwillWIN

abacus

  • Guest
Answer to your next question
« Reply #30 on: May 09, 2002, 09:07:00 AM »
Superstar, you need a better hotplate, and make sure you wrap everything in foil to minimise heat losses.

So your next question you will ask is; what will I do if i have distilled a mixture of safrole and isosafrole or you think you have.

Take your distilled mixture, add some fresh (say1% KOH or less) and heat.  If the solution stays virtually clear and your KOH flakes don't really dissolve, you have no safrole in your flask and you have iso, if it goes brown you still have unconverted safrole so keep refluxing or stirring.
 
Of course then you have to distill out the iso again but it's better than wasting all that unreacted safrole on the next steps.


Over And Out

cheeseboy

  • Guest
yuh..
« Reply #31 on: May 09, 2002, 09:59:00 AM »
You can magnetically stir through a soft style heating manlte and control the temp with a variac controller. That sounds just as good or better than the hotplate/stirrer combo.

May De Sorce Bee Wit Chu-Always

chem_123

  • Guest
mix of junk
« Reply #32 on: May 23, 2002, 04:01:00 AM »
in having this sass. oil:

pinene..........    2-10%    Bp= 154C at 1 atm
phellandrene.    2-10%    Bp= 175C at 1 atm
d-camphor....    0- 5%    Bp= 204C at 1 atm
safrole..........   80-90%    Bp= 234C at 1 atm
eugenol........    0-10%    Bp= 252C at 1 atm

as stated in

Post 294437

(LaBTop: "Prefered next steps after freezing:", Methods Discourse)

SWIM was wondering bp's are the best way to get rid of anything but safrole (except eugenol)?

SWIM's read that using a naoh solution is good to get rid of the eugenol?

if that's true, would a bee just do the naoh wash on the sass. oil before distilling (or freezing), then take time doing a distillation in order to carefully watch the temp, and then the bee will know when the safrole is coming over?

SWIM's got the brown safrole/koh mix refluxing, and was wondering...how much time is necessary for conversion? (SWIM's read overnight...but the aspirator is gonna eat up some serious water(will running it overnight make a big difference on the water bill?), so a more accurate estimate would bee nice!  ::) )

Dreaming of the sweet honey  :)

chem_123

  • Guest
transition?
« Reply #33 on: May 23, 2002, 06:15:00 AM »
SWIM's noticed that within the 4 hour time span of reflux with a 300mm vig. and a tap cooled condenser, that the drops coming from the condenser to the column off of the drip tip started clear, then went to a milky color, then back to clear...is this a good indicator that the reflux is done?

Dreaming of the sweet honey  :)

Rhodium

  • Guest
Just distill, there isn't any eugenol to speak of ...
« Reply #34 on: May 23, 2002, 06:03:00 PM »
Just distill, there isn't any eugenol to speak of in sassafras oil, according to investigations by Osmium.

chem_123

  • Guest
what about......
« Reply #35 on: May 23, 2002, 06:16:00 PM »
what about the others?:


pinene..........    2-10%    Bp= 154C at 1 atm
phellandrene.    2-10%    Bp= 175C at 1 atm
d-camphor....    0- 5%    Bp= 204C at 1 atm

safrole..........   80-90%    Bp= 234C at 1 atm
eugenol........    0-10%    Bp= 252C at 1 atm

distill and discard first bit?


Dreaming of the sweet honey  :)

Rhodium

  • Guest
Exactly. The low-boiling components is of no use ...
« Reply #36 on: May 23, 2002, 07:37:00 PM »
Exactly. The low-boiling components is of no use to us.

GOD

  • Guest
bunch of related ?'s
« Reply #37 on: September 20, 2002, 12:46:00 PM »
Swims sassy is brown, and after distillation, there is a very small amount of sediment and brown residue that obviously has a bp higher than safrole.  The oil is ~85% safrole, and takes about 3-4 cycles of freezing/thawing (at~8C) in order to remove all of the brown colored impurity, further freezing doesnt seem to clean it any further, and there still remains a little (teeny tiny bit) of cloudyness.
  Swim has performed three isomerizations that have for the most part failed (very minimal yeilds of iso).  He ASSUMES that this may have been because he couldnt find KOH anywhere in his vicinity including (finally) the chem supply which would only order a big assed drum.  The only thing he had was pH raise (solution) from the hydroponics store, he boiled it to dryness (actually scorched it) then baked in the oven.  When added to the sass, it turned dark (brown-red-almost blackish).  He applied vac for a good hour, his pump must have sucked up any moisture 'cause nothing condensed.  He tried one run with vac overnight, one run atm.  Two oxone runs yeilded very little product, and the temp for both of em never got much past 30C.
  Swim finally (after much planning and scheeming) aquired some KOH PELLETS (which hes going to lightly grind and filter w/bug screen) and is gonna give abacus' method a whirl.  The reason swim says this- is now he wonders if eugenol is present (hes got that funny sass dontcha know!)will that fuck up the isomerization as well? -so swim knows whether or not he should just go ahead and distill that sass anyway.
BTW, speaking of freezing out sass-
swim has managed to separate safrole/iso out of dirty ketone post oxone+hydrolysis . It was distilled, but for some reason, even with a vigreaux (granted it was jacketed with foam insulation, swim will switch to fleece material) everythin came over between 86 and 96C!  He has also managed to separate a bunch of safrole from his unreacted iso/safrole mix- although he has yet to confirm by atm bp (hes still in the process)- he has been alternating freezer (freezes both iso and safrole, fridge ~10C separate unfrozen supposive iso, thaw frozen safrole, reseed in fridge, separate etc....will post a new thread if successful (will check by doing both atm bp, then distilling to see if 2 fractions come over).
  As far as vac distilling goes, swims been using a ritchie yellowjacket, oil changed after every use -plus, swim finally got good silicone greece and used clamps on the vac hoses as well as using ptfe tape on vac nipples and thermo adapter- swims gotta do something about that vac, its too damned strong - even with gas ballast full open).  The adapter that fits to swims pump, its a 2-way adapter- will it harm the pump if he slightly unscrews the cap on the unused nipple?  Swim is at a loss, and doesnt have the $ to invest in a weaker pump at the moment.  Any other ideas- that wont end up doing damage to the pump?



Osmium

  • Guest
> When added to the sass, it turned dark ...
« Reply #38 on: September 20, 2002, 02:32:00 PM »
> When added to the sass, it turned dark (brown-red-almost blackish).

That's normal.
Why do people always assume that chemical reactions yield clean, colourless products? They ususally don't, not without some serious effort of cleaning up the products, especially not when using aggressive, highly corrosive reagents, employing natural precursors, are prone to side reactions and conducted at an elevated temperature!
More often than not you end up with an ugly horrible chunk of tar that has to be cleaned up extensively until it starts resembling anything remotely pure.

> Swim finally aquired some KOH PELLETS (which hes going to
> lightly grind and filter w/bug screen)

If you finally want to see some success you better leave them alone! Do NOT grind them and do not manipulate them unnecessarily. Just dump them pellets into the sassy and go ahead, as I told bees to do in the original writeup.

> The reason swim says this- is now he wonders if eugenol
> is present (hes got that funny sass dontcha know!)will
> that fuck up the isomerization as well?

I've personally analyzed several samples of sassy and never found any eugenol. And even if there were some traces present it won't matter.

> ...he should just go ahead and distill that sass anyway

Can't hurt, but assuming you only have an oil pump available you might just as well skip it.

> swim has managed to separate safrole/iso out of dirty
> ketone post oxone+hydrolysis . It was distilled, but for
> some reason, even with a vigreaux everythin came over
> between 86 and 96C!

I wouldn't expect any different! 3 compounds (safrole, cis and trans iso) with fairly close boiling points, distilled with a strong pump means shitty separation.

> swims been using a ritchie yellowjacket, oil changed
> after every use

That's unnecessary. I've used the same oil in pumps without cooling trap for well over a year.

> swims gotta do something about that vac, its too damned
> strong - even with gas ballast full open).  The adapter
> that fits to swims pump, its a 2-way adapter- will it
> harm the pump if he slightly unscrews the cap on the
> unused nipple? 

No, but it will start spewing oil mists out of the exhaust. Connect a cheap clear PVC hose to the exhaust, the oil will condense inside and flow back into the pump.
Other ways to admit air into your distillation:
* a capillary bubbling into your distillation flask (won't need any stirring anymore)
* sticking hypodermic needles into the vac tubing
* using a finely adjustable needle valve

> Swim is at a loss, and doesnt have the $ to invest in a
> weaker pump at the moment.  Any other ideas- that wont
> end up doing damage to the pump?

An aspirator!
When you do the vacuum isomerisation you don't have to suck a vacuum throughout the reflux. Just switch off the pump, or disconnect it after a while with a valve on top of your condenser. If your apparatus is fairly gas tight it will hold the vacuum for many hours. Try to adjust the vacuum so that the internal flask temp is somewhere around 120-130°C or so, that temp range worked well for me.

I'm not fat just horizontally disproportionate.

RoundBottom

  • Guest
pellets and pump
« Reply #39 on: September 20, 2002, 08:25:00 PM »
SWIM has never had a problem grinding KOH flakes to very small pieces (not to a powder), in fact, it speeds up the dissolution of the KOH into the safrole, and if you are using the method where you suck any water out first, shouldn't pose a problem.

HOW TO SAFELY REDUCE THE VACUUM FROM A "SUCK-HARD" PUMP

take a thumbtack, the kind with the plastic head as opposed to the flat metal head, and stick it in the vacuum hose (close to the working end).  when you need less vacuum, pull the tack out.  when you want more, put it back in.  don't wiggle it around while it's in the hose, or it will make the hole too large and leak air into the system.

Nymphomania is not a disease  - its a goal!  (Methadist on Rosemary Kennedy)