Performic

Soap · Fri Apr 15, 2005 6:04 am

i have read that both methanol and ethanol work for extraction after the treatment with acid. i currently dont have access to methanol (where the hell do you buy it, not at piant stores!) does ethanol work just as well, the denatured stuff i have has some methanol in it...

Spacemonkey · Fri Apr 15, 2005 7:13 am

Methanol is commonly sold under the name "Wood alcohol" or similar.
Might be of some help

ApprenticeCook · DILLIGAF

or collect it from the disto of r/c fuel... thats got methanol/nitro you can buy 20% nitro and collect the rest methanol and purify it for solvent use.

-AC

DjTime · Chemical Dj

A.C.,
We've been about this before. Just be very weary of the residual nitro that will be in the MeOH when you distill it from the 20% Nitro/Methanol RC fuel. Something like if im correct 3% of your distilled (from RC fuel) Methanol will be nitro.

anime · Fri Apr 15, 2005 12:31 pm

its yellow and blue and rhymes with meat.

IndoleAmine · Dreamreader Deluxe

Hey guys - neither ethanol nor methanol will work for EXTRACTION of anything after aequous HCl hydrolysis of a performic epoxide/glycol.

They are good reaction solvents (used for better miscibility of educt/product and aequous HCl); for extraction, you're better off using toluene or similar instead (anything thats water-immiscible!)... Laughing

(side note: it doesn't need to be MeOH; EtOH works well too)

BTW anime: I don't have to use more than 170°C bath temp. with my aspirator, it pulls 11-12mmHg if the weather is good. Just with plain cold tap water...
Maybe check your vacuum hose, and grease all joints properly with high viscosity silicone lube ("vacuum grease").

i_a

Soap · Sat Apr 16, 2005 6:41 am

yes swim knows that its also called wood alcohol. hes checked every hardware store and paint store in the area. he even whent to a diesl shop at the college and asked if anyone knew where he could get some methanol for his bio diesel experiments. it seems to be watched around here or at least banned for health reasons... distilling methanol from the rc fuel sounds nice, since theres going to be nitro in the mixture any way (al/hg reduction after performic).

IndoleAmine · Dreamreader Deluxe

Ahem - I just said:

DjTime · Chemical Dj

I guess in that case you could just add a gram more of Al. That way the reaction will be on target and not 3% short. Good Luck. and peace out....

IndoleAmine · Dreamreader Deluxe

Xactly.

More than this: the amount of Al is calculated to generate a certain amount of methylamine (in excess to ketone used), and if you use 600ml of 3% MeNO2 solvent, you have 18ml MeNO2 directly converted to MeAm. Thats not bad, since there will be still enough methylamine generated so there will be a big excess of it, making for a even higher yield. You just have to adjust the amount of Al to allow for complete reduction of the formed imine, which is done almost automatically when you prepare the foil as described and drip in the ketone as described.

Good luck!

i_a

Soap · Sun Apr 17, 2005 6:42 am

well swim should have re read teh procedures before posting. methanol is not neccesary in any step. for some reason swim thought that the formation of methylamine depended on methanol as well... oh well we all make mistakes. Embarassed

an equivelent amount of ethanol will suffice right?

tom-a-rom-rinbow · Sun Apr 17, 2005 1:16 pm

$200 or so for a 2-stage rotary vane pump will probably be the single most useful investment you make. they come rated at about .1 micron. with an actual vacuum of about 1 micron you can pull ketone at about 110 C. at that temperature it is less likely to burn (or degrade in quality) though you will then want a short vigreaux column (which can be insulated with aluminum foil) to achieve good separation. a refrigerator pump or aspirator may achieve 20 mmHg, pulling ketone around 150+ C. the aspirator depends alot on your water pressure. typically ketone boils about 20 degrees higher than isosafrole with the same setup. most folks say if your vacuum will not boil it below 180 C, yields will suffer significantly. though chromic was successful with atmospheric distillation of ketone made via the oxone process.

bee sure to thoroughly neutralize the acid residual in your ketone before distilling, and stop distilling the ketone at the first sign of the still head temperature increasing or any "stickyness" in the ketone coming over. one of the most straightforward tests of ketone quality is whether it is easy to pour when ice-cold. if it is slow, or sticky, or will not break into a stream of droplets when poured slowly from the spout of a beaker- then you probably let the oil bath get over 180 C when distilling and yields will be bad. in swim's experience one cannot satisfactorily fix sticky ketone by redistilling it, it is better to start a new performic making sure to control all parameters including 1) adding only as much water as called for 2) checking H2O2 strength by measuring its density (specific gravity).

tom-a-rom-rinbow · Sun Apr 17, 2005 1:17 pm

people put MeOH in their gasoline when the weather is cold, silly. it comes in 1/3L bottles.

yes, EtOH would work, in which case you may want to run the hydrolysis at 60 C instead of at the reflux temperature.

go read the "detailed methods for non-chemists" thread on the hive. swim has seen poor quality denatured EtOH mess up some reactions, an AcOH/Al/Hg oxime reduction for example.

IndoleAmine · Dreamreader Deluxe

If you use EtOH denatured with ketones(s), it can result in a big mess when you do reductive aminations.

No problem if you use EtOH "cut" with pthalic acid dimethyl ester for example, or den. with toluene/hexane for example...

i_a