Author Topic: Preparation of formaldehyde  (Read 242 times)

Prepuce

  • Mighty Bhagwan
  • Subordinate Wasp
  • ***
  • Posts: 100
Preparation of formaldehyde
« on: June 22, 2010, 01:50:39 AM »
Notes on previous efforts in preparation of formaldehyde. . .

Because it is possible to produce small amounts by dipping a red hot copper wire into methanol, it was believed that keeping a wire slightly above the liquid might allow continuing production of formaldehyde in a self-sustaining reaction. Results of testing this method in a variety of configurations were disappointing, however. An old organic chemistry textbook suggested that this process must be carefully controlled in terms of temperature and airflow, to be successful and avoid explosions. Because a fairly complicated apparatus was employed it was decided that this method was not very practical for present purposes.

An alternative method was attempted, the details of which follow. An important background detail is that methanol, being highly polar, readily absorbs microwave energy.

A standard microwave oven was modified by cutting a small hole through the top of the cooking chamber, large enough to accommodate 1/4" glass tubing, which would be routed from the cooking chamber to the outside of the oven.

A piece of 1/4" flint glass tubing was bent to facilitate routing from the top of a flask placed inside the microwave oven to a point on top, exterior to the oven. A balloon was taped securely over the open end of the tubing.

Approx. 5ml of methanol was added to a 125ml Erlenmeyer flask. A very thin piece of copper wire roughly 12 inches long (from a small electric motor) was sanded to remove the lacquer insulation, then wrapped around a small nail. The coiled wire was removed from the nail and added to the flask containing methanol. Approx. 100 mg of powdered copper was also added to the flask.

The flask was placed in the microwave oven, and the glass tubing was fitted to the flask with a rubber stopper. The area of the rubber stopper was wrapped with aluminum foil to prevent it from melting, ensuring that all foil edges were flattened against the flask. The oven door was closed and the power was set to high. The oven was energized, with a constant watch on the balloon. As soon as it inflated to a size indicating significant pressure buildup the oven was stopped. The flask was allowed to cool enough that most of the pressure was relieved, then the process was repeated about a dozen times. Each cycle of microwave "on time" was ten seconds or less, except for the very first which may have taken a few additional seconds to begin.

When the flask had cooled completely it was removed from the oven and the contents examined. Surprisingly it was found that the liquid had taken on a slightly yellow color. Although it was expected that the MeOH would be converted to formaldehyde, the odor was more like that of an ester, and while familiar, the name was unknown.

It is believed that the cause of this anomaly may have been cooking too long. AT the outset it was not recognized that it might be possible to carry the oxidation too far, assuming that is what happened, and the extended cooking time was thought to increase the odds of success in forming formaldehyde.

Any input on what might have actually been created during this reaction and how it might best be modified will be most welcome.

PP

Support the never ending quest for new and better hedonicants. Send your gift today to:

 N & B H Foundation, Attn. Bhagwan SP
 University of Massachusetts at Los Angeles
 PO Box 6.02 X 10^23
 Houston, MD 884411

Vanadium

  • Larvae
  • *
  • Posts: 48
Re: Preparation of formaldehyde
« Reply #1 on: June 22, 2010, 05:15:43 AM »
My only guess as to your product would be methyl formate, but honestly, a lot can happen under microwave conditions. Can you run some qualitative tests on it? I haven't looked at the literature relating to this reaction but it may be important to heat up the copper wire as well as to have the methanol in the vapor phase. I'd try that first, but besides that, I can only say that you should try pulsing the microwave for a second or so at a time as you've already suggested.

Prepuce

  • Mighty Bhagwan
  • Subordinate Wasp
  • ***
  • Posts: 100
Re: Preparation of formaldehyde
« Reply #2 on: June 24, 2010, 03:19:12 AM »
Vanadium, thanks for your suggestions. I'm not equipped for qualitative testing, but will look into the possibility that the wire needs to be heated, or that the reaction needs to take place in the vapor phase. Either or both would make good sense. I'll also try checking the solution after each application of power, and will report back here if I meet with any success.

PP
Support the never ending quest for new and better hedonicants. Send your gift today to:

 N & B H Foundation, Attn. Bhagwan SP
 University of Massachusetts at Los Angeles
 PO Box 6.02 X 10^23
 Houston, MD 884411

marakov

  • Pupae
  • **
  • Posts: 74
Re: Preparation of formaldehyde
« Reply #3 on: June 25, 2010, 03:49:26 AM »
The Cu is not heated properly Prepuce. PM me if you want to.

micro

  • Pupae
  • **
  • Posts: 70
Re: Preparation of formaldehyde
« Reply #4 on: June 26, 2010, 10:05:02 AM »
How about a system of two copper pipes over each other with a small airgap between.
The inner pipe would house a insulated nichrome heating element and a thermocouple.
The pipe aparratus vould then have a outlet on top that would allow attatching a condencer.
The bottom of the inner heating pipe is sealed and the outer pipe is fitted to a glass boiling flask via a rubber stopper.

MeOH is brought to a boil and the MeOH vapor passes thru the two heated copper surfaces and is then condenced.

It might be required to introduce more air to the aparratus to facciliate the oxidasion of the MeOH to formaldehyde. Maybe a two neck flask with a smal glass pipette or tubing extending to the bottom of the vesel. And then a small aquarium or somethin air pump providing some air flow to ensure oxidation.

Of cource all of this is merely theoretical, but it could/should work.

shroomedalice

  • Guest
Re: Preparation of formaldehyde
« Reply #5 on: July 20, 2010, 04:12:58 AM »
have you considered the nef reaction of nitromethane too formaldehyde :)

Prepuce

  • Mighty Bhagwan
  • Subordinate Wasp
  • ***
  • Posts: 100
Re: Preparation of formaldehyde
« Reply #6 on: July 21, 2010, 06:09:19 AM »
shroomedalice, I have not considered that reaction because of the difficulty in obtaining nitromethane. Thanks for the suggestion anyway.

PP
Support the never ending quest for new and better hedonicants. Send your gift today to:

 N & B H Foundation, Attn. Bhagwan SP
 University of Massachusetts at Los Angeles
 PO Box 6.02 X 10^23
 Houston, MD 884411

no1uno

  • Global Moderator
  • Foundress Queen
  • *****
  • Posts: 681
Re: Preparation of formaldehyde
« Reply #7 on: July 22, 2010, 11:28:48 AM »
There is the oxidation of ethylene glycol, which is used where they want maximum return of the deuterated carbons from ethylene glycol-d4 to give 2 mols of formaldehyde-d2 (see attached paper). You'll need lead tetra-acetate & I'd suspect toluene should work as well as benzene
"...     "A little learning is a dang'rous thing;
    Drink deep, or taste not the Pierian spring:
    There shallow draughts intoxicate the brain,
    And drinking largely sobers us again.
..."

jboogie

  • Larvae
  • *
  • Posts: 30
Re: Preparation of formaldehyde
« Reply #8 on: July 23, 2010, 11:47:58 PM »
I have not considered that reaction because of the difficulty in obtaining nitromethane.

i dunno... it pretty easy to go to a hobby store and just buy a gallon. its about $20USD a gallon. you can even buy it unadulterated, without the cylinder lubricant. its available online from quite a few vendors. and if ya dont wanna have it shipped, you can get it at the track shop (if you live in a redneck friendly area like myself) or an RC enthusiast shop.

the hazmat fee actually cost more than the fuel, but its really available everywhere OTC in the US.

Quote
100% Pure Nitromethane 1-1 gallon can (shipping Fuel cost 17.99 + 41.99 Hazmat)

no1uno

  • Global Moderator
  • Foundress Queen
  • *****
  • Posts: 681
Re: Preparation of formaldehyde
« Reply #9 on: July 26, 2010, 12:13:32 PM »
And ethylene glycol is available for nothing by the hydrolysis of PET, lead tetraacetate is made (per the directions - take careful note, it is something a LOT of people have wanted a procedure for)...

I'm fucked if I'd be trying to do anything with nitromethane, yeah you can buy it but it is an awfully expensive route. The other alternative is to add HCl to hexamine & heat - the mass of formaldehyde generated will, quite literally, take your fucking breath away (ie. use a hood & proper equipment).
"...     "A little learning is a dang'rous thing;
    Drink deep, or taste not the Pierian spring:
    There shallow draughts intoxicate the brain,
    And drinking largely sobers us again.
..."

Prepuce

  • Mighty Bhagwan
  • Subordinate Wasp
  • ***
  • Posts: 100
Re: Preparation of formaldehyde
« Reply #10 on: July 29, 2010, 02:40:45 AM »
Sounds like there are several options for making formaldehyde, certainly more than I expected. FWIW ethylene glycol is engine coolant/antifreeze, so there should be no need to buy it.

Heating HCl and hexamine sounds like a very convenient way to do it.

PP
Support the never ending quest for new and better hedonicants. Send your gift today to:

 N & B H Foundation, Attn. Bhagwan SP
 University of Massachusetts at Los Angeles
 PO Box 6.02 X 10^23
 Houston, MD 884411

drone1240

  • Subordinate Wasp
  • ***
  • Posts: 105
Re: Preparation of formaldehyde
« Reply #11 on: July 29, 2010, 08:05:47 PM »
Heating HCl and hexamine sounds like a very convenient way to do it.

PP

It is a convenient or at least viable way to make to make a list one chem as well. Be aware that is what your actions and intentions will be interpreted as....when it smells like dead fish in the bat cave.
acting in accordance with the dictates of reason....

Prepuce

  • Mighty Bhagwan
  • Subordinate Wasp
  • ***
  • Posts: 100
Re: Preparation of formaldehyde
« Reply #12 on: August 02, 2010, 03:09:53 AM »
Sorry, drone1240, but I don't follow. Are you saying that a list 1 chemical (which one?) is produced in addition to the formaldehyde, or that formaldehyde is a list 1 chem?

PP
Support the never ending quest for new and better hedonicants. Send your gift today to:

 N & B H Foundation, Attn. Bhagwan SP
 University of Massachusetts at Los Angeles
 PO Box 6.02 X 10^23
 Houston, MD 884411

Vesp

  • Administrator
  • Foundress Queen
  • *****
  • Posts: 3,130
Re: Preparation of formaldehyde
« Reply #13 on: August 02, 2010, 04:04:10 AM »
He is talking about the formation of methylamine during the reaction between hexamine and hydrochloric acid, which is a list one chemical. Methylamine has the smell of fish.
Bitcoin address: 1FVrHdXJBr6Z9uhtiQKy4g7c7yHtGKjyLy

drone1240

  • Subordinate Wasp
  • ***
  • Posts: 105
Re: Preparation of formaldehyde
« Reply #14 on: August 11, 2010, 03:17:45 AM »
Hydrolysis of hexamine with HCL to yield MeNH2. I didnt know that formaldehyde was created so we both learned something. My apologizes for not articulating myself better.
acting in accordance with the dictates of reason....

jon

  • Foundress Queen
  • *****
  • Posts: 1,883
Re: Preparation of formaldehyde
« Reply #15 on: August 11, 2010, 05:47:28 AM »
your place will smell like rotten pussy if you don't aspirate that down a drain.
i'll give a good explanation to this later.
and trust me if you work with methylamine everyone notices it on you.
you could say your a pornstar or something like that.
the stuff gets on you.