Purification of OTC Paraformaldehyde

[nbk2000]

I finally broke down and bought myself a box of Campa-Chem dry chemical toilet deodorizer, which is paraformaldehyde.

And, as I expected but hoped not, it is blue dyed. :(

I'm not sure if the dye would have any effect on making hexamine, or whether it'd carry through the nitration process to result in smurf colered RDX :D, but I'm willing to give it a go.

But, it'd also be nice to be able to be rid of the blue shit in my shit, nigga. ;)

I'm thinking sublimination, but I'm not sure if it subliminates, or simply decomposes.

I've attached a picture showing what the para looks like.

Any suggestions, or has anyone else tried using this material in a process?

BTW, it might make a good area denial material. I spread about a tablespoons worth out in the yard, and hours later it still is unpleasant to stand downwind from the spot. I could envision sprinkling a bit of it about in areas where you don't want little pikers to hang out at.

I've got just the spot in mind for testing. It's a pedestrian train overpass that the local teenies hang out at and posture for each other at. It's annoying to have to walk through the crowd of lil' shits.

[blazter]

I have taken a few stabs at washing off the blue dyes on campa chem. Methanol seemed to do the job well, and cold water seemed to do just as good as job much cheaper.

As for attempting to produce hexamine from the washed solids...well thats where the trouble comes in. Adding the white cleaned solids to clear household ammonia solution and boiling does seem to dissolve the paraformaldehyde with difficulty. HOWEVER, as the solution becomes more concentrated, a scum of sorts seems to appear, and on the sides of my glassware a rather tenacious soap scum deposited :mad: This scum that precipitated did not appear to be crystaline at all, in fact it appeared to be some sort of detergent. Evidence that this white scum is detergent is observed by the white film that was left on the glassware. Even scrubbing with abrasive sponges hardly touched it, I finally had to soak it in full strength muriatic acid. I am quite sure that the ammonia is not to blame since I used it a while ago to prepare some NH4Cl by neutralizing it with HCl.

As for subliming it, that was the only method that seemed to show promise. The thing to really watch out for is suckback which is what killed my heating "flask". I used an old bottle and stuffed a bit of tubing in the end of it and led the vapors to a bit of water. White fumes were produced which appeared to condense as a solid in the water IIRC. I never continued with the sublimation route because of a lack of suitable glassware to use.

[nbk2000]

Sounds more like you were doing a vacuum distillation, rather than a sublimination.

I'm going to try it using a jar and a metal pan full of iced water. The heated vapors should condense on the bottom of the pan as crystals (hopefully), unless it decomposes on heating into gaseous formaldehyde.

I figured there was some sort of "added" crap in my crystals. My hexamine came out blue and crunchy, looking like instant coffee crystals...only bluer. :p

Unfortunately, the manufacturer of the chemical doesn't have a website, nor a phone number that I've been able to find. :( So no MSDS yet to tell me how much para there actually is in the shit.

[vulture]

Adding the white cleaned solids to clear household ammonia solution and boiling does seem to dissolve the paraformaldehyde with difficulty

You first have to break down the polymeric paraformaldehyde into formaldehyde, because paraformaldehyde is nowhere as reactive as the very reactive formaldehyde.

Heating does decompose paraformaldehyde into formaldehyde, which has a very low boiling point. You'll need to dissolve it in water.

[inFinie]

Paraformaldehyde (trioxan, 1,3,5-trioxacyclohexane) is stable in acidic condition (no more details like btw. which pH's). So maybe adding some base like NaOH will decompose it to HCHO, NH3 is a base indeed. But i'm not sure NaOH will work. This was from a school book.
To prepare HCHO trioxan is heated.
In some resources paraformaldehyde is stated as a polymer, and in some it is stated as a trimer. I am not sure which one is true.

[mongo blongo]

If your goal is to make Hexamine then maybe it would be a good idea to decompose your OTC paraformaldehyde by heat and bubble the resulting formaldehyde into ammonium hydroxide.

[nbk2000]

That's what I'm going to do. :)

Though it'd have been nice if it was pure enough to use in the Para/AcO/NO3 reaction for RDX production. :(

[vulture]

Purification isn't that hard, considering that your product will probably contain dyes and other crap with a rather high boiling point. Simple destillation or absorbing in water could easily reach 98% purity, even more if it doesn't contain any other very volatile substances.

BTW, you got AcO? :eek:

EDIT: Just got an email from a certain Tri-x who can't post because he reregistered himself.

Anyways, he sent me the link for the MSDS:

http://www.thetford.com/msdsforms.cfm

[nbk2000]

I wish I had AcO, but that's in the future, once I build a ketene generator. :)

You have no idea how hard it is finding someplace local that sells black rubber stoppers. :( It's easier to score drugs than find a rubber stopper in this town! :o How fucked up is that?

[Tuatara]

Got a brewers supply shop there, NBK? They'd have rubber stoppers, both plain and single hole. Not a great size selection usually, but 'beggars can't be choosers' as the saying goes.

[bombtech]

Well, I've been browsing the forums for some time now and finally have worked up the nerve to post a reply (and hopefully not getting banned or fragged to hard!).

NBK,
have you been able to successfully purify your campa-chem? I also bought some of this for the synth of hexamine and was pretty ticked off to see it was not pure.

Also, I recently purchased some trioxane. can this be used in the same manner as the para to evolve formaldehyde? Would the para/trioxane be disolved in water before heating or is this done dry? When this is heated and the resultant formaldehyde gas is fed into some water, how can I measure the resulting concentration, i.e. density(specific gravity), weight? or does this even matter for the hex synth?


please be gentle!!!

[bobo]

I did hexamine and it seems not to matter what stoichiometry you use. I used too much ammonia and a very good yield was obtained after boiling off water and ammonia. The ammonia was rather pure though (25% or something). If you want to try leading formaldehyde gas through water why not lead it to ammonia immediately?

[bombtech]

if the stoichiometry is not so important, then thats what I would do. I just want to make sure I'm not wasting to much of either.

[bobo]

The losses of home scrubbing are probably considerable depending on your setup. Bubble size affects diffusion of course but also retention time so the thing to do is disperse. With a funnel on a tube I got the ammonia smell through the house very strongly when concentrating from 5%:(

The free ammonia and formaldehyde worry me more than the inefficiency.

[Zio Matrix]

This is a pretty old thread, I dunno if anyone's still trying to clean OTC paraformaldehyde, but:

I have a box of Coleman's dry holding tank cleaner, and it seems to be somewhat less contaminated than the Campa-Chem stuff, as it only took about 5 rinses to get out most of the blue dye as opposed to 10 for the Campa chem, and the "perfume" seems to wash out as well. Sadly, the only place I've been able to find the Coleman's stuff is at K-Mart a while back, and they don't seem to stock it anymore, but I just thought I'd let you all know to snap it up if you find any, because it's certainly easier to purify than that CC shit.