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black copper oxide and AP


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#1 Dan

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Posted 27 December 2004 - 03:06 AM

i wanted to make some blue stars using ammonium perchlorate. i only have black copper oxide though. i was wondering if it is safe to mix these.
thanks
Dan

#2 BurlHorse

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Posted 27 December 2004 - 01:46 PM

i wanted to make some blue stars using ammonium perchlorate. i only have black copper oxide though. i was wondering if it is safe to mix these.
thanks
Dan

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Yes, it's relatively safe, It's used in Blue Strobe Rockets and Several other formulae, I've never had or seen or heard of a problem.

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#3 paul

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Posted 27 December 2004 - 02:17 PM

Copper itself and it?s salts act as a catalyst in AP compositions. When using AP either KClO4 or copper salts are added to increase the burn rate. And the copper salts are there to give the comp a blue color, too.

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#4 Dan

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Posted 28 December 2004 - 12:30 AM

cool thanks just wanted to make sure

#5 cat

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Posted 07 January 2005 - 04:28 PM

POSTED BY: donald haarmann - - Jan 25 1998, 12:00 am



PGI Bulletin No.
41, March, 1984

SAFETY OF COPPER/BRASS SCREENS WITH CHLORATE
COMPOSITIONS
by _ The WiZ (donald j haarmann)


(The following article was in response to Ed Raszkowski's Question in PGI
Bulletin No. 38.)


Dr. McLain and Donald Lewis; Effects of Phase Change in Solid-Solid
Reactions-1966, [my copy courtesy of E.R.], determined that when a mixture
of potassium chlorate was doped with copper chlorate, and then ground with
purified sulfur [a brave move], the mixture detonated spontaneously after
being let stand undisturbed on a shelf for only thirty minutes! The experiment
was repeated using the same components, simply placed in a plastic vial
and mixed by "tumbling the vial approximately ten minutes about its major
axes." After approximately twenty-four hours of standing behind a barricade,
a similar detonation occurred. [A less complete discussion of this work is
reported in Dr. Milan?s book; pg. 78.]


They concluded as a result of these experiments that; "Aside from the
spectacular, the finding that a potassium chlorate could be made which when
;nixed with sulfur is spontaneously detonable at room temperature there is a
byproduct(s) of this experiment."


The doctrine of using brass, bronze or copper screens, tools and
jigs for pyrotechnic mixing and loading for non-sparking
properties certainly needs to be reexamined in light of these
findings. Emphasis added]


The warning is repeated by Ellern.


J.C. Shumacher; Perchlorates: Their Properties, Manufacture and Use; page
206+ff reports that the "***decomposition [of ammonium perchlorate] was
strongly catalyzed by powdered copper metal or cupric oxide, and to a lesser
extent by sodium chlorate, lithium or potassium dichromate." "emphasis
added]


even more importantly he states on page 215:


For example a number of fires in the drying and packaging
equipment of the AMMONIUM perchlorate plant of Western
Electrochemical Company (now American Potash dc Chemical
Corporation) were found to have been caused when the
perchlorate crystals came into contact with copper tubing in the
vibrating pan-dryer heat exchanger. When stainless steel was
substituted for copper the fires ceased. Ammonium perchlorate
was found to be most sensitive to ignition at a moisture content of
0.02 to 0.5 per cent, [how dry are your stars?], particularly when it
is contaminated with copper and possibly in the presence of other
metallic contaminants. This experience confirms other reports of
the accelerating effect of copper on the thermal decomposition of
ammonium perchlorate, and pyridine perchlorate. [Emphasis
added.]


The development of cheap electricity during the later part of the 19th century, was
followed by the first commercial electrolysis of chloride solutions for the production of
sodium chlorate by the French in 1866. As a result of this process large amounts of
chlorates became available at reasonable cost. It soon followed that because chlorate
mixtures had "at all times fascinated inventors on account of the large amount of
oxygen stored up in *** chlorate(s), which can be given off so readily," these cheap and
readably available chlorates (sodium, potassium, ammonium) were soon used for the
production of explosives. In 1890, electrolysis of sodium chlorate, lead to the pro-
duction of potassium and ammonium Perchlorates for use in the production of
explosives. Although few of these chlorate/perchlorate based explosives ever found
favor in this country, they were widely used i!1 Europe. Their use having in all cases
been supplanted by the introduction of ammonium nitrate based blasting agents.
Because of an increasing number of accidents resulting from the use of chlorate
explosives, the US Bureau of Mines performed "Frictional Impact" testing of chlorate
explosives between September, 1911 and February 1, 1919. [Why they took eight
years to complete these tests is not recorded!] The results were reported in: Bureau
of Mines; Tech. Paper 234, 1919.


Investigated was: "A certain potassium chlorate explosive that is used in the United
States and is designated Chlorate Explosive B." [Potassium chlorate, sugar, gum
arable]. The mixture had come under suspicion because a number of premature
explosions had occurred during its use in bituminous coal mines. Quoted from the
report are the following examples:


1. "While inserting copper needle in a charge *** the charge exploded."
2. "The charge exploded while the copper needle was being inserted in the charge
bore hole."
3. "While pushing a 12-inch cartridge into bore hole, with copper needle inserted
about 6 inches in it, *** charge exploded."


They felt that: In view of the frequency of these accidents and the seeming ease with
which they took place, not being explainable by the sensitiveness of the
explosive itself to friction, it was considered advisable to determine, if possible,
the cause of the excessive sensitiveness to friction.


It was thought, as practically all bituminous coals contain pyrite, perhaps the pyrite
was the cause of the accidents. [Now time out for a little mineralogy -- Pyrite or
"Fools Gold" is iron-sulfide (FeS2), it can with time break down to form, iron oxide
and sulfur. Its cousin Marcasite also FeS2 decomposes rather easily into ferrous
sulfate and sulfuric acid!]


To the explosive B mixture was added coal dust (basically carbon, and generally not
considered safe with potassium chlorate, by most pyros) and finely ground pyrite.
?/hen the mixture was stirred with a copper needle it ignited! Unfortunately the paper
does not report any tests performed on explosive "8" without the added pyrite/coal
dust, with a copper wire.


"Pendulum friction" tests, were also performed, [This test was developed to replace the
then standard "broomstick" test i.e. beat on a sample of the explosive with a broomstick
and if it fails to detonate, or crack when tested repeatedly, it receives a passing grade!]
on various chlorate explosives, ever they failed to repeat the same tests with either
pyrite and/or coal added, and then compare the results. Despite these shortcomings it
was concluded that the detonation of the explosive was due to the increase in "Friction
Sensitivity" as a result of the added pyrite. In light of current information it would appear
that the real cause of the premature ignition may have been the copper wire!
Due to shortages of raw materials during WW II, large amounts of chlorates and
Perchlorates were produced. As a result the US Bureau of Mines felt that at
war's end: "Promoters may seek to market explosives containing these
ingredients, ***" Therefore in December 1945, they issued Information Circular
#7340; Hazards from Chlorates and Perchlorates in Mixtures with Reducing
Materials.


One part of this report is of interest. Due to a fatal accident that occurred during
the manufacture of practice land mines. A sample of the material [ingredients
not stated, other than the fact that it contained potassium n perchlorate,
possible the military potassium perchlorate, barium nitrate, aluminum flash
mixture.] was tested in a "pressure friction apparatus."


The test: consists essentially of a cylindrical brass plunger that exerts a fixed
pressure and rotates at a fixed speed upon a small weight of the
sample contained in a brass cup. Only materials exceedingly
sensitive to friction, such as the initiating explosives, will fire in this
test. The mixture ignited during the test and was found to have a
friction sensitivity slightly less than that of mercury fulminate.
[Emphasis added.]


Once again the source of ignition may have been copper ions from the brass!
Although hard evidence is lacking, it would seem certain that careful pyros will
avoid using copper dust, in any of their comps. And will refrain from using
copper/brass screens when processing mixtures containing chlorates if not
Perchlorates. In the older literature there can be found stars made using
combinations of potassium chlorate, and sulfur, along with various copper salts
(copper sulfate, etc.) these are not recommended for use, as even then they
had a bad reputation.


Mixtures containing Sulphur and a Chlorate, Black oxide of Copper
or Sulphide of Copper (and probable all Sulphides and Sulphites)
with chlorate should be avoided. Purple fires which generally contain
one of the above compounds of Copper have an especially bad
name for going off spontaneously. - C.T. Brock, 1872.

#6 adamw

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Posted 07 January 2005 - 11:57 PM

Very interesting reading. Thankyou for that. Something to bear in mind!
75 : 15: 10... Enough said!




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