From: maize@bragg.bio.purdue.edu
Newsgroups: rec.juggling
Subject: Re: Coloured Flames - FAQ answer
Date: 25 Jan 93 21:52:06 GMT
Article-I.D.: mentor.C1FJEw.G85
Reply-To: maize@bragg.bio.purdue.edu
Organization: Purdue University, Dept. of Biological Sciences

In article <1993Jan25.141653.14526@craycos.com>, rh@craycos.com (Robert Herndon) writes:
>As a safety comment, I would STRONGLY RECOMMEND AVOIDING the
>use of lithium perchlorate with methanol.  Lithium perchlorate
>is a strong oxidizer; mixed with a good fuel, such as methanol,
>one possible result is a potent and rather unstable explosive.
>Lithium perchlorate is also likely to eat one's torch wicks up,
>although I cannot (and will not) verify this through personal
>experience.

  I have used lithium perchlorate in methanol as a torch fuel.  
I also do not recommend it from a standpoint of safety.  It does eat
wicks up, also the screws and metal sheathing and then the dowel
wood underneath.  
  But lithium perchlorate, itself, is not terribly unstable.  Organic
perchlorates are  --  but they can't be formed just by mixing lithium 
perchlorate and methanol (for example.)  
  Methanol, by itself, burns with a pale, wimpy blue flame.  With
the addtion of lithium or sodium perchlorate the flame becomes
very bright and large.  I think tiny deposits of the metal perchlorates
do form on the wick during burning and explode in sparks.  

>
>A secondary possibility is that as the wick dries, particularly
>after repeated uses, lithium perchlorate will build up in and on
>the wick, turning it into explosive.
>

  Could happen, but I think the build-up mainly explodes during a 
burn anyway -- thus no large build-up tends to occur.  The real problem
could be lithium perchlorate seeping into the dowel and perhaps reacting
over time with the wood.  

>All in all, I would *STRONGLY* recommend staying away from
>perchlorate/fuel mixtures.  They've maimed many people over
>the years.

  I basically agree with this.  The mention of lithium perchlorate 
should probably be omitted from the FAQ.  If you're really that into 
getting the perfect red torch flame (and lithium perchlorate -- while
hazardous -- is the perfect red) you can find out about it from 
pyrotechnicians or chemists.  
  Actually, unless you're a fire artist/technician like Ken, I'm 
pretty sure the colored flame is not worth the trouble.  All those 
bottles of fuels mixed with salts to tote around, all the salt-encrusted
wicks you have to deal with, the smell of solvents in your car and 
apartment, the fretting about whether the methanol fumes are slowly 
blinding you or the combustion products of the metal salts are some
new, unforeseen carcinogen or chronic exposure toxin, the sight of your
torches disintegrating and the cost of replacing them, and the guilt
of borrowing your friends' torches and destroying them as well cannot be 
worth the few seconds of seeing those gorgeous colors.  Believe me,
I've been there.


_______________________________________________________________________
Phillip SanMiguel               Purdue
maize@bilbo.bio.purdue.edu       Institute for
                                  Molecular    "We'll do anything
  Bennetzen Lab                    Plant          for funding."
                                    Science
_______________________________________________________________________
Organization: Masters student, Information Networking Institute, Carnegie Mellon, Pittsburgh, PA