Dany
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Nitryl cyanide: synthesis, properties and potential applications in EM science
In a recent article published in the Angewandte Chemie journal a team of scientist from the Loker Hydrocarbon Research Institute and
Department of Chemistry synthesized a small but very important molecule called nitryl cyanide [1]. It’s structure is shown below:
Synthesis:
Nitryl cyanide was synthesized by reacting nitronium tetrafluoroborate (NO2BF4) with tert-Butyldimethylsilyl cyanide
(tBuMe2SiCN) in nitromethane (CH3NO2) as a solvent at -30°C:
Fractional condensation was used for the purification of nitryl cyanide. A yield of 40% of nitryl cyanide (with >95% purity) was obtained after
three fractional condensation.
Properties:
Nitryl cyanide is a colorless liquid at room temperature. It’s melting point is -85+/-1°C. The density of the liquid at -79°C is 1.24+/- 0.08
g/cm<sup>3</sup>. Nitryl cyanide is stable at room temperature, quotes from [1]:
“The thermal decomposition of NCNO2 was studied by heating the compound in a stainless steel cylinder, separating the products by
fractional condensation, and analyzing them by IR spectroscopy. Heating for one hour to 50 and 100°C, respectively, resulted only in little
decomposition with most of the NCNO2 being recovered unchanged, and heating to 140°C for several hours was required to achieve complete
decomposition. The major decomposition products were CO2 (80 mol% based on carbon) and N2, but smaller amounts of NO and some
NO2 and N2O were also observed...”
Importance as an energetic material:
The heat of formation of nitryl cyanide in the liquid state was estimated to be +43.9+/-2 kcal/mol which is pretty high for a small molecule. The
molecule of nitryl cyanide has a zero oxygen balance: one mole of nitryl cyanide yield one mole of nitrogen (N2) and one mole of carbon
dioxide (CO2). Nitryl cyanide behave as an excellent propellant, quotes from [1]:
“As NCNO2 has an excellent oxygen balance and a large positive heat of formation, it might be of interest as a high energy density
material (HEDM). We have estimated the specific impulse (Isp, rocket propellant performance) of NCNO2 in vacuum, and predicted a value of
343 s. This value can be compared to 240 s for hydrazine. It even exceeds that of a standard (NO2)2/hydrazine bipropellant by 10
s.”
The authors didn’t mention any detonation performance for nitryl cyanide. Based on the reported density and heat of formation, I calculate the
detonation performance (detonation velocity and pressure) using the BKW thermochemical code [2]:
DCJ= 6.62 km/s
PCJ= 158 kbar.
These generally low detonation performance are directly linked to the low condensed density (1.24 g/cm<sup>3</sup> of nitryl cyanide.
Nitryl cyanide as an important building block for other energetic materials:
Theoretical calculations have shown that many molecule displays excellent performance as explosive and propellant. Two of these molecules are shown
below:
The properties of 2,4,6-trinitro-1,3,5-triazine are taken from [3] while the performance of the cubane derivative was taken from [4]. These two
theoretical molecules are very interesting as explosive and propellant. Nitryl cyanide has been proposed as a building block for the formation of the
two molecules shown above [5]:
The calculations shows that the reaction is exothermic (ΔE(0°K)= -70.2 kcal/mol) for reaction (2) which is due to aromatic stabilization of
2,4,6-trinitro-1,3,5-triazine.
Conclusion:
Nitryl cyanide has been synthesized with moderate yield (40%) from nitronium tetrafluoroborate (NO2BF4) and
tert-Butyldimethylsilyl cyanide (tBuMe2SiCN) in nitromethane (CH3NO2) as a solvent at -30°C. Nitryl cyanide is a
liquid with a density of 1.24 g/cm<sup>3</sup> and is stable at room temperature. The calculated energetic performance shows that nitryl
cyanide possess excellent propellant performance (Isp= 343 s) and moderate to low detonation performance (calculated via BKW thermochemical code).
Nitryl cyanide is also a potential building block for the synthesis of other interesting energetic molecules, namely 2,4,6-trinitro-1,3,5-triazine and
1,3,5,7-tetranitro-2,4,6,8-tetraazacubane.
References:
[1] M. Rahm, G. Bélanger-Chabot, R. Haiges, K. O. Christe, Angew. Chem. Int. Ed. 2014, 53, 6893-6897.
[2]Mader, C. L. 1963. Detonation properties of condensed explosives computed using the Becker-Kistiakowsky- Wilson equation of state. Report LA-2900.
Los Alamos Scientific Laboratory
[3] YAKUP ÇAMUR, A COMPUTATIONAL STUDY ON NITROTRIAZINE DERIVATIVES, MIDDLE EAST TECHNICAL UNIVERSITY, 2008, Master thesis.
[4] Peter POLITZER, Pat LANE and Jane S. MURRAY, CEJEM, 2011, 8(1), 39-52.
[5] Peter POLITZER, Pat LANE and John J.M. Wiener, cyclooligomerizations as possible routes to cubane-like systems, OFFICE OF NAVAL RESEARCH, contract
N00014-99-1-0393, 1999.
Dany.
[Edited on 15-12-2014 by Dany]
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deltaH
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Quite the breakthrough Dany, thanks for the excellent report!
If nitryl cyanide was trimerizable, would they not have seen evidence of that in their characterisation, particularly in this step: "Heating for one
hour to 50 and 100°C, respectively, resulted only in little decomposition with most of the NCNO2 being recovered unchanged
...", especially in light of it being a liquid.
I have a sneaky suspicion thermodynamics might be favouring the reverse of those reactions, i.e. de-trimerization into nitryl cyanide. These
compounds have surely been heavily studied by ab initio calculations, so theoretical dGf's are perhaps available for a back of the envelope
Keq calculation for the gas phase?
[Edited on 15-12-2014 by deltaH]
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Bert
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| Quote: |
“As NCNO2 has an excellent oxygen balance and a large positive heat of formation, it might be of interest as a high energy density material (HEDM).
We have estimated the specific impulse (Isp, rocket propellant performance) of NCNO2 in vacuum, and predicted a value of 343 s. This value can be
compared to 240 s for hydrazine. It even exceeds that of a standard (NO2)2/hydrazine bipropellant by 10 s.”
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The (estimated) Isp is promising- Storage stability seems decent. Reactivity? TOXICITY?
If it's to be used as a mono propellant, what is the mechanism to decompose it in the motor?
The yield on synthesis was rather poor, and lab method at least looks costly. Any prospects for a cheaper synthesis...
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PHILOU Zrealone
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Thanks Dany,
Very nice finding and infos
I will comment deeper later on this compound and related multimers.
For now on, I'm just curious about the detonation parameters you calculated...if you go just 7 degrees Celcius lower in temperature, you would be
below the melting point of the molecule; the density would then be higher and close to 1,348 g/ccm (if it display aliphatic properties) or to 1,400
(if it display aromatic properties - due to the triple bond -C#N and conjugated -N(=O) of the nitro group).
--> Could you redo the calculations of Dcj and Pcj with that info? Thanks in advance .
BTW, I wonder what is precisely the impact of the freezing/lowering of the temperature on the detonation parameters, since density is temperature
dependant; dillatation coefficients might be considered reversely as a contraction coefficient and expands or constricts the material linearly over
wide temperature areas (dillatation/contraction coefficients are larger for organic materials than for mineral or metalic materials...what is good
news for this specific energetic material application)...
--> Theorycaly absolute zero would result in maximum density but the explosive material migh become unsensitive, or at a certain stage lose power
due to the heat capacity of the material that has to be integrated from zero to ambiant temperature into thermodynamic calculations...
--> Each explosive might display an optimum minimal temperature to maximise density and output energy without loosing initiability!
Hereunder the results from Engager's Sciencemadness detonation utility program for the 3 densities...
[Edited on 17-12-2014 by PHILOU Zrealone]
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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franklyn
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It's good to know finally that it can form and surprisingly is so stable.
The cost of the precursors will limit practical application although it is impressive as a propellant.
Assuming +44 Kcal/mol , Enthalpy of reaction comes to -1917 kcal/mol
NO2CN => CO2 + N2
There is only a handful of energetic molecules that are near to this.
A speculation I had
http://www.sciencemadness.org/talk/viewthread.php?tid=6717#p...
and someone else
http://www.sciencemadness.org/talk/viewthread.php?tid=925
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[Edited on 18-12-2014 by franklyn]
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deltaH
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@franklyn
| Quote: | | Enthalpy of reaction comes to -1917 kcal/mol |
Are you talking about an enthalpy of decomposition for nitryl cyanide at STP? I calculate -50 kcal/mol or -2.9 MJ/kg... which is quite low for an
energetic (compare -4.184 MJ/kg for the unit of TNT equivalent).
[Edited on 18-12-2014 by deltaH]
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Dany
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The first theoretical study (via ab initio method) performed on nitryl cyanide and it's isomers was performed by Anatoli KORKIN and Rodney
BARTLETT back in 1996 [1]. They predicted that nitryl cyanide and two of it's isomers should be stable and observable experimentally. The two other
isomers are shown below:
The stability decrease as one goes from nitryl cyanide to isomer (II).
Nitryl cyanide> (I) > (II). However (I) and (II) should be observable.
deltaH if the authors didn't get any polymerization product from heating this doesn't mean that the idea of using nitryl cyanide as
precursor for the formation of the triazine and azacubane is wrong. Nobody said that only by simple heating you will get the desired polymerization
products. Maybe the formation should be carried out using a catalyst or via light irradiation using photochemistry.
Bert, nothing is said about the toxicity of nitryl cyanide. However this compound is reactive. Nityl cyanide is incompatible with
fluorides, Lewis acids [BF3 and B(C6F5)3], elemental mercury, amines, and K3PO4.
For a given propellant, the exact mechanism of decomposition and the nature of decomposition products as well as their quantity in a rocket motor is
the one million dollar question. This is so difficult to predict due to the high combustion temperature encountered in a rocket motor which influence
the chemical equilibrium for the different reaction that may occur in this environment.
Philou, the Dcj and Pcj of nitryl cyanide at 1.348 g/cm<sup>3</sup> and 1.4
g/cm<sup>3</sup> are:
For 1.348 g/cm<sup>3</sup>: D= 6.96 km/s; P= 187 kbar.
and
1.400 g/cm<sup>3</sup>: D= 7.13 km/s; P= 201 kbar.
Thanks for your own detonation calculation but these calculations should be checked for errors. I see that you have used 43.9 kJ/mol for your
calculation while the true unit is kcal/mol...a big difference.
Also, the detonation temperature are constant in all your calculations at the three density which is impossible.
References:
[1] A. A. Korkin, J. Leszczynski, R. J. Bartlett, The Journal of Physical Chemistry 1996, 100, 19840-19846.
Dany.
[Edited on 18-12-2014 by Dany]
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deltaH
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| Quote: | | deltaH if the authors didn't get any polymerization product from heating this doesn't mean that the idea of using nitryl cyanide as precursor for the
formation of the triazine and azacubane is wrong. Nobody said that only by simple heating you will get the desired polymerization products. Maybe the
formation should be carried out using a catalyst or via light irradiation using photochemistry. |
Thanks again for the great post. One comment though, a catalyst will not help if the reaction if it is thermodynamically unfavourable, so I still
think it's very important to do a basic calculation before entertaining the notion. It's a pity I don't have access to molecular modelling software
anymore, an ab initio calculation of dGf for a gas phase nitryl cyanide and trinitromelamine is trivial because of the high symmetry of the
latter and small size of the former. Do you know anyone who does?
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Bert
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| Quote: |
If it's to be used as a mono propellant, what is the mechanism to decompose it in the motor?
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What I meant to ask was not the specifics of the decomposition reaction- Although that's obviously of great interest.
But how the decomposition would be initiated in a rocket's combustion chamber. Contact with an electrically heated grid or some catalytic material?
Hypergolic chemical(s) injected as a "starter"?
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3. Mention anything you have learned from your target.
4. Only then are you permitted to say so much as a word of rebuttal or criticism.
Anatol Rapoport was a Russian-born American mathematical psychologist (1911-2007).
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deltaH
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This molecule looks highly reactive (speculative, I know, but some reasoning why below), so I doubt you would need a catalyst to decompose it. Your
main problem would be preventing detonation or progression of a deflagration from the exhaust into the fuel tank. 
I might be wrong, but perhaps it would behave similar to the insanely toxic cyanogen halides or cyanogen itself. The nitro group is strongly electron
withdrawing and I would hazard a guess that the C-NO2 bond in that molecule is weak and easily dissociated.
Since it's so new... I'd treat it as extremely toxic and able to detonate, until proven otherwise.
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franklyn
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I don't know why this is such a problem, it's as basic as can be if you do the math.
* Note : Engager's detonation application posted by PHILOU Zrealone indicates a
heat of explosion 6.07 MJ/Kg . Divide this by 4.186 converts to Kilogram Calories.
~ 1450 kcal. Heat of explosion is characteristically less than a calorimetric bomb result.
Anyway subtracting + 44 heat of formation from - 94 heat of formation of CO2
+ 44 . . . . . - 94
NO2CN => CO2 + N2
yields -138 Kcal/mol heat of reaction ( or autocombustion , as you please ) per mole.
Divide a kilogram (1000 gm) by mol weight of the compound 72 gm , is 13.889 ,
this multiplied by 138 gives -1917 kcal per kilogram.
This is no different than the decomposition of H2O2 or N2H4 except there is additionally
heat of combustion from carbon and oxygen.
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Dany
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Thanks franklyn, for the calculation and for the correction.
Bert here's an interesting patent about monopropellant ignition methods
Patent: Method for initiating the combustion of hydrazine
Dany.
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Dany
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The author who synthesized nitryl cyanide didn't mention how they calculate the specific impulse Isp which is 343 s for this compound.
we present here a simple (but rough) formula for the rapid estimation of Isp. This formula can be applied to monopropellant as well as to
bipropellent (e.g., H2-O2 system).
The unit of Isp is the second. If one mole of nitryl cyanide decompose into one mole of CO2 and one mole of N2, the
heat liberated is Q= -138 kcal/mol. The molecular weight of the gases is 72 g/mol. Using the above formula, one get an Isp= 367 s, which is
relatively close to the value of 343 s given in the paper. (the absolute value of Q is used).
For more information on this formula see the following report:
Rosen, G. Final Report for Project Propulsion Applications of Free Radicals and Electronically Excited Metastable Species
Dany.
[Edited on 19-12-2014 by Dany]
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deltaH
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Since I had fun with 'burning' dimethylcyanamide with the open simulation software COCO, I figured I could give this a stab too.
STEP ONE: Adiabatic flame temperature calculation
This one was considerably more challenging than combusting dimethylcyanamide. My original idea was to approximate nitryl cyanide as one mole each of
carbon, nitrogen and oxygen and feed that into the Gibbs reactor model to get a composition and adiabatic flame temperature. I would have simply added
the heat of formation of nitryl cyanide as an energy feed stream into the reactor to account for the difference in enthalpies.
However, carbon is not a listed component in the databank, so I had to be a little shifty 
What I did is to feed one mole of benzene as my carbon source, then split off the water after combustion, cool it to STP and add this heat back into
the Gibbs reactor. I then also subtracted the heat of formation of benzene and water from the heat of formation of nitryl cyanide entering as the
energy stream.
I have a funny feeling I've got a sign error in there somewhere 
So by going this roundabout route, I've done the thermodynamic equivalent (hopefully) of feeding in carbon. Thermodynamics is not path dependent... so
one just needs to draw a big black box over the whole thing and make sure that the IN's and OUT's are correct and accounted for.
Anyhow, the simulation is attached below, if you haven't installed COCO by now... do it... it's damn powerful and versatile!
The adiabatic flame temperature, tentatively, is a whopping ~4100°C
Not really surprising considering that this is a non-water producing EM, but still, it's f@$ing high.
Interestingly, it's so high, that a significant amount of CO2 is dissociated to CO and O2, in other words, while it has an OB of 0, the
REAL/effective OB is quiet +ve and so the monopropellant would benefit from mixing with another. This could go some way to stabilising it by
dilution and also lower effective costs (once an alternative synthesis is found)?
There's also lots of nitric oxide in the there as well.
The decomposition products per mole of nitry cyanide decomposed by equilibrating at 4100°C are:
0.265 mol. O2
0.936 mol. N2
0.342 mol. CO2
0.658 mol. CO
0.128 mol. NO
Please someone check this for me, attached simulation below. Once we're all satisfied with this, I can proceed with the ISP calculation by working out
an nozzel exhaust velocity and finally the ISP.
EDIT: Corrected too much oxygen in feed error, originally was feeding 9 moles O2 per mole of benzene, should have been 7.5 moles O2, which it is now.
Attachment: nitryl cyanide combustion.fsd (249kB)
This file has been downloaded 626 times
References:
Download COCO from http://www.cocosimulator.org/
[Edited on 19-12-2014 by deltaH]
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PHILOU Zrealone
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True that polymerization might require higher temperature than the decomposition temperature of O2N-C#N and so the use of other milder polymerization
pathway or catalyst should be used.
Dany,
The heat of explosion is calculated and extrapolated/interpolated on the basis of Heat of formation of compound and detonation products based on
equilibrium constants...so there is no density dependance of the explosion heat in Engager's utility program.
Thanks for the correction, I was misleaded by other HOF you provided for triazine and tetraazacubane in kJ/mol.
Below, I have redone the calculations on the basis 43,9 kcal/mol = 183,8 kJ/mol. That way it sticks perfecly to Franklyn calculations -1917 kcal/kg =
8024 kJ/kg...
Engager's program stops calculations for heat of explosion, pressure, VOD, explosion temperature at 135 kJ/mol for Keshavarz but heat of explosion
continue further with Eisenstad.
I have done linearisation between 0 kJ/mol to 185 kJ/mol for all parameters and found the following values by extrapolation (quite effective because
very linear):
Heat of formation: 183,8 kJ/mol
Heat of explosion: 8014 kJ/kg
Explosion temperature: 6261 °K
d = 1,24 g/ccm
VOD = 7094 m/s
p det = 274 kbar
d = 1,348 g/ccm
VOD = 7538 m/s
p det = 324 kbar
d = 1,400 g/ccm
VOD = 7747 m/s
p det = 350 kbar
Quote: Originally posted by Dany  |
deltaH if the authors didn't get any polymerization product from heating this doesn't mean that the idea of using nitryl cyanide as
precursor for the formation of the triazine and azacubane is wrong. Nobody said that only by simple heating you will get the desired polymerization
products. Maybe the formation should be carried out using a catalyst or via light irradiation using photochemistry.
Philou, the Dcj and Pcj of nitryl cyanide at 1.348 g/cm<sup>3</sup> and 1.4
g/cm<sup>3</sup> are:
For 1.348 g/cm<sup>3</sup>: D= 6.96 km/s; P= 187 kbar.
and
1.400 g/cm<sup>3</sup>: D= 7.13 km/s; P= 201 kbar.
Thanks for your own detonation calculation but these calculations should be checked for errors. I see that you have used 43.9 kJ/mol for your
calculation while the true unit is kcal/mol...a big difference.
Also, the detonation temperature are constant in all your calculations at the three density which is impossible.
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PH Z (PHILOU Zrealone)
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Dany
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Philou and deltaH thanks for the calculations. Philou, The calculated detonation pressure (350
kbar) is too fantastic for a density of 1.4 g/cm<sup>3</sup>. I will stick to my reliable thermochemical code calculations. You
can try to repeat the calculation of DCJ and PCJ (we are not interested in Q or TCJ right now) with the simple method
of Kamlet and Jacobs [1] which is known to be very reliable. deltaH, proceed to the Isp calculation based on your method
to see if you will obtain a value close to 343 s.
In connection with nitryl cyanide, it seems that trinitromethyl cyanide exist, and had existed long time ago.
The only english language paper which mention trinitromethyl cyanide is the article of WILSON et al. [2] published in 1947. Quote from [2]:
"Trinitromethane (nitroform) was first prepared by Schischkoff (Annalen, 1857, 101, 216) by the action of water or alcohol
on trinitromethyl cyanide, and later several methods for its preparation from tetranitromethane were described..."
I've searched the old Annalen journal (which is now the European journal of organic chemistry, EurJOC) and found I found the 157 years old
paper which is written in German. I've attached the paper below so if one of the members (Philou?) knows German he can help us to
understand what the paper said about trinitromethyl cyanide (reactivity, synthesis, etc...).
References:
[1] M. J. Kamlet and S. J. Jacobs, “Chemistry of Detonation. I. A Simple Method for Calculating Detonation Properties of C, H, N, O Explosives,”
J. Chem. Phys. 48 (1), 23–35 (1968).
[2] W. S. Reich, G. G. Rose, W. Wilson, Journal of the Chemical Society (Resumed) 1947, 1234-1237.
Dany.
Attachment: German paper on trinitromethyl cyanide.pdf (230kB)
This file has been downloaded 440 times
[Edited on 20-12-2014 by Dany]
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deltaH
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Results of the more accurate ISP calculation are in:
Ve = 2380m/s
ISP = 243/s
It is much lower than expected, possibly because of the lack of low molecular weight products, particularly water and it's dissociation products.
EXCEL calculation attached.
k data taken at 4000C without interpolation.
Reference:
Method and constants from http://www.thespacerace.com/forum/index.php?topic=1481.0
[Edited on 20-12-2014 by deltaH]
Attachment: ISP calculation nitryl cyanide.xlsx (12kB)
This file has been downloaded 546 times
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Dornier 335A
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Okay, my turn to contribute with some calculations.
Detonation performance calculated with slightly modified versions of Keshavarz's formulas and no equilibrium:
1.24 g/cm3
DCJ = 7330 m/s
PCJ = 193 kbar
1.4 g/cm3
DCJ = 8010 m/s
PCJ = 245 kbar
These numbers are likely overestimated because the program assumes complete combustion at the CJ-point, i.e. NCNO2 → N2 +
CO2.
When I ran the compound through my equilibrium program I got the following figures (for 1.24 g/cm3):
TCJ = 5887 K
PCJ = 162 kbar
ISP:
deltaH, the calculated ISP from the article was in vacuum. When I changed Pe in your Excel calculation to 0, I got 285 s.
I also tried replacing your values with my own calculated temperature and product composition (http://i.imgur.com/sJNeX8l.png) . With Pe = 0 atm I got 337 s at a chamber pressure of 68 atm, and 361 s at a chamber pressure of 1000 atm.
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PHILOU Zrealone
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@ Dany,
A trimeric form (triazine related) of trinitromethyl cyanide also exists (tris-trinitromethyl-triazine).
It is stable and made from nitration of (-N=C(CH2CO2H)-)3 (the CO2H group is split off and the triazine ring resists oxydation).
An article of this was provided by Nicodem somewhere into the forum.
An article about it also exists on wikipedia.
http://en.wikipedia.org/wiki/2%2C4%2C6-Tris(trinitromethyl)-...
In principe methatesis should be possible between nitroformiate and cyanuric halides...
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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deltaH
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Dornier 335A, your ISP calc. methodology seems similar to mine, any idea's for the deviation? 285/s vs 361/s is a big difference...
any obvious error you can see in my approach or is this all because of the simulated product composition and temperature?
PHILOU Zrealone, this reminds me of my thread on the exhaustive nitration of creatine, also making use of the acetate and chopping
off one carbon to leave the trinitro moeity.
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Dornier 335A
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deltaH, I'm not sure you used your calculated 4100°C to get the velocity of the exit gases. The bold part in the formula is the
temperature, isn't it?
=SQRT((2*F12/(F12-1))*(8314,51*(2750+273,15)/H12)*(1-(D26/D25)^(F12-1)/F12))
With 2750 replaced by 4100, the formula gives 343 s with Pe = 0 atm.
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deltaH
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Ah that's it, thanks Dornier 335A for spotting the mistake, yes I should have reference the temperature cell in the formula, that
temperature was still the old one from my dimethylcyanamide calculation. Well done for spotting it!
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franklyn
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Here is the post by Nicodem
http://www.sciencemadness.org/talk/viewthread.php?tid=1970&a...
That paper requested by Rosco Bodine available here
http://www.sciencemadness.org/talk/viewthread.php?tid=1970&a...
Obtained and provided in references by ayush
http://www.sciencemadness.org/talk/viewthread.php?tid=19098&...
related post
http://www.sciencemadness.org/talk/viewthread.php?tid=11195&...
other related
http://www.sciencemadness.org/talk/viewthread.php?tid=17012&...
http://www.sciencemadness.org/talk/viewthread.php?tid=17012&...
I think estimates are conservative. Performance must be close to known nitrocarbons.
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PHILOU Zrealone
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Post by Nicodem posted on 27-3-2012 at 17:50
In Energetic materials subforum
Tread: New Energetic Materials - Current Research
PH Z (PHILOU Zrealone)
"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
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