Nickel hydrazine nitrate (NHN), (chemical formula: [Ni(N2H4)3](NO3)2 is an energetic material having explosive
properties in between that of primary explosive and a secondary explosive.[1] It is a salt of a coordination compound of nickel with a reaction equation of 3N2H4·H2O + Ni(NO3)2 →〔Ni(N2H4)3〕(NO3)2 ＋ 3H2O[2]
Improperly made (Hard chunks, grains of sand consistency)
Preparation
NHN can be synthesized by reacting nickel(II) nitrate hexahydrate with a dilute aqueous solution of hydrazine monohydrate at 65 C.[4] To help speed the drying of the product after filtration from the hot water, it can be rinsed with alcohol. The product is a fluffy powder (density=0.9 g/cm3). To increase its bulk density to (1.2 g/cm3), dextrin in the amount of (1%) of the weight of the nickel(II) nitrate hexahydrate can be added.[5]
Non-primary explosive detonator (NPED)
The sensitivity of NHN straddles the line between highly sensitive primaries and a sensitive secondary, so it can be considered a true non-primary explosive detonator (NPED).
Another benefit of NHN is that it will make the DDT (deflagration to detonation transition) in a cardboard shell, eliminating the danger of shrapnel from a metal shell.
Safety
NHN straddles the line between primary and secondary. Because of this it is a relatively safe explosive to work with having 80x less sensitivity to friction (16.0 N) than lead azide (0.1N) as shown in table 2.
Friction sensitivities of some traditional explosives (lead azide – 0.1N; lead styphnate – 1.5 N; mercury fulminate (white) – 5.0 N;
tetrazene – 8.0 N; PETN – 60 N; RDX – 120 N; HMX – 120 N, show that NHN is not very sensitive, and is thereby not exceedingly hazardous in handling.[6]
Table 1. General and structural properties of Nickel hydrazine nitrate[1]
Molecular formula
Ni H12 N8 O6
Formula weight
278.69
Color
Purple Violet
Crystal density (g/cm3)
2.1
Average particle size (μm)
13
Nickel content (%)
21.16 (21.06) a
Hydrazine content (%)
34.46 (34.45) a
Nitrate content (%)
44.47 (44.49) a
Nitrogen content in coordination sphere (%)
30.25 (30.14) a
FTIR peaks, (cm−1)
3238, 1630 (NH2); 1356,1321 (-NO3)
Moisture content (at 333 K for 10 min) (%)
0.34
Average mol wt of combustion products
27.35
Percent condensable Ni (l)
18
Oxygen-fuel ratio
0.8571
Oxygen balance %
-5.74
a Values in brackets are theoretical
Table 2. Comparative properties of Nickel hydrazine nitrate, lead azide and lead styphnate[1]
Property
Nickel hydrazine nitrate a
Lead azide b
Lead styphnate
Crystal Density (g/cm3)
2.129
4.38
3.02
Oxygen balance (%)
– 5.74 c
– 5.50
-19.00
Heat of combustion (kJ/kg)
5225
2635
5234
Heat of formation (kJ/mol)
– 449
469
-385
Heat of explosion (kJ/kg)
4390
1610
1912
Pressure output in closed vessel (100 mg in 48 cm3) (kg/cm2)
a Experimental value, b literature value, and c theoretical value
References
^ abcHariharanath, B.; Chandrabhanu, K. S.; Rajendran, A. G.; Ravindran, M.; Kartha, C. B. (2006). "Detonator using Nickel Hydrazine Nitrate as Primary Explosive". Defence Science Journal. 56 (3): 383–9. doi:10.14429/dsj.56.1904 (inactive 4 December 2024).{{cite journal}}: CS1 maint: DOI inactive as of December 2024 (link)
^Xiang, Dong; Zhu, Weihua (15 February 2018). "Thermal decomposition of energetic MOFs nickel hydrazine nitrate crystals from an ab initio molecular dynamics simulation". Computational Materials Science. 143: 170–181. doi:10.1016/j.commatsci.2017.11.006.
![Properly made (talcum powder like consistency)[3]](File:Nickel_Hydrazine_Nitrate.jpg)
