From: mvp@netcom.com (Mike Van Pelt)
Newsgroups: rec.pyrotechnics
Subject: Re: Potassium Nitrate
Message-ID: <mvpCJ8Asn.BDp@netcom.com>
Date: 6 Jan 94 22:07:34 GMT

In article <2gfj3b$st8@menudo.uh.edu> crf@cfox.bchs.uh.edu (Chris Fuller) writes:
>  Last I check, KMnO4 wasn't supposed to be directly combined with ANY fuel.
>e.g., I seem to remember a text file about taking a glass bottle and giving it
>3 or 4 drops of gas, closing it up and swirling it until it coats the inside,
>adding a few drops of KMnO4 solution and hurling it at something....  Never
>tried that, though, and you know how those crazy texts are.... could be a hoax.

Well, my super-duper glassware cleaning solution (KMnO4 dissolved in
conc. H2SO4, a *green* solution, by the way) would instantly ignite
anything ignitable that it came in contact with -- paper towels,
ethanol, and random organics in the "waste solvent" can.

It sufficed to remove bakelite from test tubes, thus preventing me from
having to pay $.50 to replace the tube that that lab gunked up.  But
now that I know more, I would be a *lot* more cautious about this mix.
Especially, I would make certain that anyone I gave my "magic cleaning
solution" to was completely clear on the fact that it must not be
poured into the waste solvent can after use.

Caveat detonator.
--
Mike Van Pelt                       When the fog came in on little cat feet
mvp@netcom.com                      last night, it left these little muddy
KE6BVH                              paw prints on the hood of my car.

From: nreitzel@lonestar.utsa.edu (Norman L. Reitzel   )
Newsgroups: rec.pyrotechnics
Subject: Re: Potassium Nitrate
Message-ID: <1994Jan7.015033.15271@ringer.cs.utsa.edu>
Date: 7 Jan 94 01:50:33 GMT

In article <CJ8IAq.Apn@world.std.com> moroney@world.std.com (Michael Moroney) writes:
>mvp@netcom.com (Mike Van Pelt) writes:
>
>>Well, my super-duper glassware cleaning solution (KMnO4 dissolved in
>>conc. H2SO4, a *green* solution, by the way) would instantly ignite
>>anything ignitable that it came in contact with -- paper towels,
>>ethanol, and random organics in the "waste solvent" can.
>
>That would be either permanganic acid (HMnO4) or manganese heptoxide
>(Mn2O7).  Both are extremely powerful oxidizers as you discovered,
>but be careful I think the latter can explode.

It all depends on how much permanganate and how much sulfuric acid.
Manganese Heptoxide (Mn2O7) is a green oily liquid at room temperature.
It is relatively safe when dissolved in sulfuric acid - that is, it's
about as safe as chromate glass cleaners.  However, it is only soluble
to the extent of about 3% in 100% H2SO4, and 7% in 90% H2SO4.

If you get too much permanganate, the manganese oxide separates as oily
droplets, and they are of the same order of sensitivity to shock as
nitroglycerine.  In short, Mn2O7 is nothing to have around.  Moreover,
as Mike M. points out, it ignites on just about anything organic, and
once ignited, it explodes quite nicely.

I first performed this experiment when I was 15, and carefully isolated
about 2 ml of the green oil.  I even heat-sealed it in a glass ampuole.
When I was disposing of the residue which still contained substantial
oxide, I threw the 10 ml bottle it was in into the trash can.  There was
a bright orange flash, a loud explosion, and one side of the trash can
was opened up like with a can opener.  Fortunately for me, the side that
peeled open was the side away from me.  My parents were highly irate.
Worse, I started sweating the ampuole of oxide - like, what was I going
to do with it?  How to get rid of it?  I opted for taking it outside
(carefully) and shooting at it with a BB-gun.  When hit, it provided
a very nice bright orange fireball and a very respectable report.  My
neighbors were not impressed, but then, I was always making explosions.

--------------------------------------------------------------------------
  Norman L. Reitzel, Jr.       |    "When you live beside the graveyard,
  nreitzel@lonestar.utsa.edu   |       you can't cry for every funeral."
  Blue Water Ventures, dba.    |                         Russian Proverb
  ------------------------------------------------------------------------

From: mvp@netcom.com (Mike Van Pelt)
Newsgroups: rec.pyrotechnics
Subject: Re: Potassium Nitrate
Message-ID: <mvpCJErKM.31K@netcom.com>
Date: 10 Jan 94 09:55:34 GMT

In article <40.386.2421.0NE15C30@channel1.com> jack.treger@channel1.com (Jack Treger) writes:
>MV>Well, my super-duper glassware cleaning solution (KMnO4 dissolved in
>MV>conc. H2SO4, a *green* solution, by the way) would instantly ignite
>MV>anything ignitable that it came in contact with ...
>
>  The safe glass cleaning solution is H2SO4/dichromate (sodium or
>  potassium).  It's known as Chromerge (tm) and is similar in
>  oxidative cleaning power to H2SO4/permanganate but is not explosive.

Well, I tried to use the dichromate solution to remove the bakelite
from my test tube, and it didn't seem to do anything to the bakelite.
That's when I decided to up the ante with the permanganate.  The
bakelite immediately turned from a yellowish transparent solid to an
opaque white rapidly disintegrating solid.

Could be some chemical peculiarity of bakelite, I suppose.
The dichromate didn't ignite paper towels on contact, either.

>  Very unpleasant and should be avoided. If you need an oxidative
>  cleaner then Chromerge is recommended (but be careful there too-
>  it's very corrosive to skin and hexavalent chromium is carcinogenic).

I suspect the permanganate would be no more healthy.  But I agree,
this mix was a bad idea, and I wouldn't do it now.
--
Mike Van Pelt                       When the fog came in on little cat feet
mvp@netcom.com                      last night, it left these little muddy
KE6BVH                              paw prints on the hood of my car.

From: mvp@netcom.com (Mike Van Pelt)
Newsgroups: rec.pyrotechnics
Subject: Re: Potassium Nitrate
Message-ID: <mvpCJEr1z.2rC@netcom.com>
Date: 10 Jan 94 09:44:22 GMT

In article <CJAIJn.yEv@yuma.ACNS.ColoState.EDU> heyjoe1@lamar.ColoState.EDU (David Keeler) writes:
>>Mike Van Pelt (mvp@netcom.com) wrote:
>>: Well, my super-duper glassware cleaning solution (KMnO4 dissolved in
>>: conc. H2SO4, a *green* solution, by the way) would instantly ignite
>>
>Are you sure the "green" solution contained permanganate and not
>potassium dichromate?>

Absopositively.  I was quite surprised at the time, purple KMnO4
crystals producing a green solution.  Others have posted the possible
products here:  Permanganic acid and manganese heptoxide, both of which
are green.  And potent oxidizers, which I knew (that was the whole
point of the mixture) and in the case of Mn2O7, explosive, which I wish
I had known at the time.  I *probably* didn't make Mn2O7, but it was
more luck than anything else.
--
Mike Van Pelt                       When the fog came in on little cat feet
mvp@netcom.com                      last night, it left these little muddy
KE6BVH                              paw prints on the hood of my car.

From: mvp@netcom.com (Mike Van Pelt)
Newsgroups: rec.pyrotechnics
Subject: Re: Potassium Nitrate
Message-ID: <mvpCJJo5M.K3y@netcom.com>
Date: 13 Jan 94 01:29:45 GMT

In article <1994Jan11.043653.6302@cs.rochester.edu> dietz@cs.rochester.edu (Paul Dietz) writes:
>Ullman's encyclopedia says [Mn2O7] is green-black in reflection, and
>reddish in transmitted light.

*Whew*.  Good. The solution I made was transparent green, when looking
though a tube of it at a light.

I knew, of course, that anything flammable would go off in the
KMnO4/H2SO4 solution, but it never occurred to me that the combination
itself might be an explosion hazard if I had happened to use more
KMnO4.  And apparantly it didn't occur to the lab instructor who saw
me do it, either.

--
Mike Van Pelt                       When the fog came in on little cat feet
mvp@netcom.com                      last night, it left these little muddy
KE6BVH                              paw prints on the hood of my car.

From: mvp@netcom.com (Mike Van Pelt)
Newsgroups: rec.pyrotechnics
Subject: Re: Potassium Nitrate
Message-ID: <mvpCJLBs4.M8t@netcom.com>
Date: 13 Jan 94 22:57:37 GMT

In article <1994Jan13.180140.22610@hpcvaac.cv.hp.com> billn@hpcvaac.cv.hp.com (bill nelson) writes:
>mvp@netcom.com (Mike Van Pelt) writes:
>: In article <1994Jan11.043653.6302@cs.rochester.edu> dietz@cs.rochester.edu (Paul Dietz) writes:
>: >Ullman's encyclopedia says [Mn2O7] is green-black in reflection, and
>: >reddish in transmitted light.
>:
>: *Whew*.  Good. The solution I made was transparent green, when looking
>: though a tube of it at a light.
>
>Hm, if it is supposed to be reddish in transmitted light, then you had
>better check again. You were viewing your sample by transmitted light.

Right: I was glad I *wasn't* making Mn2O7.  I wasn't trying to make
an explosive, just remove some bakelite from a test tube.

I didn't know about Mn2O7 when I did this.

--
Mike Van Pelt                       When the fog came in on little cat feet
mvp@netcom.com                      last night, it left these little muddy
KE6BVH                              paw prints on the hood of my car.