formula of red gum

[MadMat]

Anyone know what the chemical formula for red gum is? I have tried looking it up to no avail. I want to do some stoichiometric calculations.

 

[CaverCork]

Well, that's a good question. An in depth search revealed that supposedly it is 70 to 80% kino tannic acid, C₁₈H₁₈O_{8. Not sure what the other 20 or 30% is yet. Not sure if what I found is correct either. I'll keep looking for a bit. There is a mention of it being similar to catechu, from which catechin (}C₁₅H₁₄O₆) and catechol (C₆H₆O₂)is derived. I think I spelled those correctly. Good luck!

 

Addendum: I also found this, but I haave no idea what they are talking about. "Red gum, [85% para-coumaric ester of xanthoresinotannol, accaroides resin, yacca gum]. Organic fuel, binder (alcohol solvent)."

Edited April 7, 2016 by CaverCork

[MadMat]

Yeah that's kind of what I found as well. I am starting to guess that accaroides resin is the majority of the make up of what we use as "red gum". I would at least like to get a ratio (by weight) of replacement for other commonly used pyro fuels.

Edited April 7, 2016 by MadMat

[Mumbles]

This thread may be of some use. You can use fuel values or oxygen demand to help with substitutions even if an exact formula is now known. http://www.amateurpyro.com/forums/topic/6756-fuel-value/

 

There are some of these sorts of tables in Shidlovskiy's Principles of Pyrotechnics. They can also help to be put into context based upon fuels of known composition like hexamine, lactose, charcoal, etc. Red gum is a natural product, and as such is subject to some compositional variability anyway.

[MadMat]

Thanks Mumbles

[taiwanluthiers]

It's a natural resin so asking for the chemical formula for Red Gum is like asking for the chemical formula of gasoline... it's a mixture of stuff.

 

To find out the fuel value you will actually want to burn it in a bomb calorimeter, Then you can derive how much oxidizer is needed for a complete burn. However many pyro literature will have that information.