Light traps, ethel Acetate and greasy specimens

Kurt Jacobs morphidae at
Fri Apr 28 19:26:41 EDT 2000

> Kurt Jacob's stated:
 Supposedly soaking specimens in acetone for a few hours will
> remove oils, but my tinkering with this technique have shown a reduction
> brightness of color of the scales on the wings.

Well, I tried this technique again with sphinx moths, and the acetone
soaking was very successful!  My first try with acetone soaking was with a
few Morphos and I wasnt that happy with the results.  One note with the
acetone soaking of sphinx moths.  It seems that 1-2 hours is sufficient, but
I did soak a very greasy Pachysphinx modesta overnight, and it took the
grease off the body even, but the wings did get a little wrinkled, (looks a
little like an unironed shirt).  The acetone soaking also is going to make
the specimens very brittle and also the wing tips will tend to turn up.

Leroy Koehn wrote.
> I have used Ethel Acetate for over twenty years in light traps. I have had
> the typical greasing of specimens in my collection. Some from light traps,
> and some from a sheet that were killed in cyanide jars. The greasing of
> specimens is cause by body fats in the specimens. Whenever I degrease
> specimens, I have use ether, with lit or no effect on the specimens. This
> includes females of Speyeria diana.
> I am not a salesman for Ethel Acetate, I would prefer to use are more
> effective chemical and one that is not as flammable. A small spark can
> a fire or explosion.  However, Ethel Acetate is available and cost
> for me. I am also very careful when I use it.

Ethyl acetate is the only dispatching agent that i use also, but it must be
used with care because of the fire hazard.  As far as soaking in ether to
remove body oils, I wouldnt give it a try if I had some, look at the flash
point and lower explosive limit below.  Acetone is dangerous, but much safer
than ether for many reasons.  I would guess that acetone is much less
expensive too, as low grades are readily available on store shelves at 2
dollars a pint.  The lower explosive range for Ethyl acetate given below was
found on an internet site, and it looks fishy too me.  0.6 % is much lower
than I would expect since the flash point is relatively high.

Ethyl Acetate (an ester):  Flash Point = 24 deg F
Diethyl Ether (an ether, daa): Flash Point  = - 49 deg F (MINUS 49
Acetone (a ketone): Flash Point = 15 deg F

Acetone : Explosive Range = 2.6 - 12.8 percent by Volume in Air
Diethyl Ether : Explosive Range = 1.85 - 48 percent by Volume in Air
Ethyl Acetate : Explosive Range = 0.6 - 10.7 percent by Volume in Air

One other note about ethers.  They can form organic peroxides which can
become concentrated as the ether is used.  The organic peroxide formation is
catalyzed by light.  This is why ethers are never stored in glass
containers.  Ethers are typically stored in metal cans.  Organic Peroxides
are very very very explosive.  And I stress the very.  The recomendation on
ether is discard 30 days after opening or 1 year if unopened.  Another
problem with ether is that it is 2-1/2 times heavier than air when in the
vapor form.  So the concentration could get pretty high down by your knees
without your nose realizing it.  I couldnt find any vapor density numbers
for the others, but ether is the one that the textbooks always mention for
their high vapor density values.

Kurt Jacobs

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