Oxygen Balance

[UnderConstruction]

I noticed several explosives on megalomania's website that mention it, I've been learning about it for a couple of weeks and it seems like something that's worth looking into. I spent five or six hours yesterday figuring the OB of many of the explosives on the site. Since the forum was down it gave me time to expand it considerably. Here's a list of what I have so far, except I fear that several of them may be incorrect because a mistake in finding the molar mass. If megalomania's site gives a mass for the compound in question, you can trust that the OB is right.

Oxygen balance ensures complete detonation and eliminates carbon monoxide and NOx gases, so it's worth expanding upon



This is the formula:


OB=-1600/Mol. Wt. of Compound*[2X*+(Y/2)+m-Z]

where
X=No. of carbon atoms
Y=No. of hydrogen atoms
Z=No. of oxygen atoms
m=No. of metal atoms


---------------
Results:
---------------
*Urea Nitrate (0%)
*EGDN (0%)
Nitrogen Sulfide (0%)


( - )

Ethanolamine dinitrate (-9.46%)
PETN (-10.1%)
HNIW (-10.95%)
Pentanitroaniline (-15.088%)
PETRIN Acrylate (-15.888%)
Silver Fulminate (-21.348%)
RDX (-21.6%)
HMX (-21.6%)
FOX-7 (-21.6%)
Guanidine Nitrate (-26.2%)
DINGU (-27.57%)
DNI (-30.36%)
Nitroguanidine (-30.748%)
EDNA (-31.978%)
Styphnic Acid (-35.9%)
Nitrosoguanidine (-38.07%)
Potassium Picrate (-41.9%)
EDDN (-42.98%)
Dinitrochlorobenzene (-43.44%)
CL-18 (-44.07%)
PVN (-44.9%)
Picric Acid (-45.39%)
Tetryl (-47.36%)
CL-14 (-49.86%)
NONA (-51.6%)
Guanidine carbonate (-57.7%)
DATB (-58.84%)
PYX (-60.51%)
DIANP (-69.25%)
DNPA (-70.335%)
Trinitrotoluene (-74%)
*Aluminum Powder* (-89%)
Propylpicrate (-91.44%)
HMTD (-92.2%)
NPN (-98.96%)
IPN (-98.96%)
*Sulfur* (-100%)
HNO (-122.6%)
Allyl Hydroperoxide (-151.1%)
Acetone Peroxide (Trimer) (-151.2%)
benzenediazobenzyl
hydroperoxide (-166.5%)
*Carbon* (-266.7%)


( + )

nitroglycerin (+3.5%)
TNGU (+4.96%)
Heptanitropentane (+6.19%)
Ammonium Nitrate (+20%)
Barrium Perchlorate (+20.4%)
Silver Perchlorate (+23.15%)
Lead Perchlorate (+27.58%)
Mercury Perchlorate (+28.03%)
Uranyl Perchlorate (+30.7%)
Potassium Dinitramide (+33.07%)
Ammonium Perchlorate (+34%)
Hydrazine Diperchlorate (+34.3%)
Potassium Perchlorate (+34.64%)
Cadmium Perchlorate (+35.97%)
Strontium Perchlorate (+39.08%)
*potassium chlorate* (+39.2%)
Sodium Perchlorate (+39.2%)
Trinitromethane (+42.37%)
Zinc Perchlorate (+42.38%)
Copper Perchlorate (+42.67%)
Cobalt Perchlorate (+43.43%)
Nickel Perchlorate (+43.47%)
Manganese Perchlorate (+44.1%)
*sodium chlorate* (+45%)
Calcium Perchlorate (+46.86%)
sodium nitrate (+47%)
Tetranitromethane (+48.969%)
Magnesium Perchlorate (+50.17%)
TitaniumTetraperchlorate (+53.84%)
Aluminum Perchlorate (+54.09%)
Lithium Perchlorate (+54.4%)
Nitryl Perchlorate (+59.46%)
Nitrosyl Perchlorate (+61.79%)

*although the compound contains carbon,
hydrogen, and oxygen, it still has an OB of zero
because the CH&O balance each other out to 0

*....* denotes non-explosive material
often applied to explosives

[Charles Owlen Picket]

If the amount of oxygen, expressed in weight percentage, liberated AS A RESULT of the complete conversion of the explosive material to CO2, H2O SO2, etc. - this is positive OB. If the amount of oxygen bound in the explosive is insufficient for the complete oxidation reaction - we have negative OB. Commercial explosives need to have a OB close to zero to minimize toxic gases; this is one of the criteria for "permissables". However I have found that the statement: "oxygen balance ensures complete detonation" is not entirely correct. Example would be a quality primary like lead azide. Hell, we could look at a lot of explosives with negative OB that detonate very efficiently but leave behind toxic gases. The big ones are carbon monoxide & nitrous oxide. A positive OB limits that and in a mine or closed area, that's damn important.

OB can start to get confusing depending on testing dynamic & source. I remember that MHN had a positive balance according to Federoff as did ETN. Many energetics materials that are mfg with an active base will most likely have a positive one obviously. Many but not all nitric esters will have a positive OB. There are so many variables in the phenomenon of detonation that chemical composition alone allows for effective and complete detonation but never ensures it. Thus we have the phenomenon of "over-driving" a detonation.

[UnderConstruction]

You obviously know a good deal on the subject, mind you though that I said "ensures complete detonation", not that it was dependent. I understand though that oxygen balance isn't a necessity, it still seems like something that could aid the explosive community if the information was readily on hand (I think it might me interesting enough for megalomania to incorporate it into his explosives page, but it looks like he's had his hands full more than lately, lately).

[Charles Owlen Picket]

It's not that complex a subject in itself but it's easily misinterpreted. It's certainly a worthy subject for discussion. The discussion can open new viastas by demanding further study to grasp at the utilitarian aspects. Here are two related questions:
Can an energetic material have both a neutral and non-neutral OB? Would that (OB) affect performance and under what conditions? Many people have these questions in the back of their head when they first learn about this subject.

Cook wrote a simple but well rounded chapter on this subject.

[megalomania]

I long ago made the decision to not include too much extraneous data unrelated to a synthesis, and although I have seen many occurrences of calculated oxygen balances in my references, I don’t use them. A detonation velocity is about as much non synthesis related I get on the site. I prefer to leave information on the use and formulation of explosives up to someone else, or else I would never have time to concentrate on the syntheses.

I do agree that knowing what oxygen balance is, how to calculate it, and how it can be useful is valuable. If someone is willing to write the info up I can and will incorporate it into my website. This is part of what I want to accomplish with the user contribution feature.

[UnderConstruction]

You're welcome to do anything with the information I put up there, that being why it was put up to begin with :)

Also, I found an oxygen balance calculator in the Similar Threads place, here:
http://www.roguesci.org/theforum/showthread.php?t=3464
(look on the second page)

I also found a calculator for molar mass:
http://www.lmnoeng.com/molecule.htm

Here's the start of a continued list:

PGDN (-28.9%)
Dinitrophenol (-78.215%)

TNEF (+4.27%)
BTNEC (+15.837%)

[Man Down Under]

I suck at math, so I'll ask what's Tetraethyl Leads' OB?

(CH3CH2)4Pb = C8H20Pb
MW=323.44

If the problem could be worked out in a stepwise manner, it'd clarify some problems I had with the original formula, such as what are the *? They're used in two different places and contexts. And is it NEGATIVE 1600?

Reason I ask is because I saw an old patent for making an extremely-sensitive liquid binary explosive using TeNM and TEL, which was stated as having a VoD of over 9300m/s. :eek:

I'll have to look to find it again, but it'd be nice to know if the patent was accurate or bunk.

[UnderConstruction]

you don't need to be great at math if you can learn how to work the online calculators (* is often used to avoid being confused with an x when multiplying).

A problem I found with the online calculator I gave the link to when finding your OB was that it doesn't incorporate any metals present, do not use it in any metal-containing explosive.
Use this for metal-containing explosives, though it is less user-friendly:
http://www.math.sc.edu/cgi-bin/sumcgi/calculator.pl
Insert -1600/MW[(2X)(Y/2)+m-Z] into the calculator of the above link and replace the variables listed in my first post.

Also yes, it is negative 1600. Also / is divided, * is multiplied, - is negative and then subtracted (-Z).


the OB of Tetraethyl Lead is -133.56%

[dhemor_]

Hey, while I think of it, here's an oxygen balance calculator I coded a few days ago. It's programmed in c++, and both the source + an executable are available for download.
http://twitch.uflox.com/?page_id=13

I hope it's of some use.