Nickel-hydrazine nitrate complex

Zhu, S., Wu, Y., Zhang, W., Mu, J. Evaluation of anew primary explosive Nickel hydrazine nitrate (NHN) complex. Propellants Explosives Pyroteclmics 22, 317-320 (1997)... 

Transition metal hydrazine perchlorate, nitrate, and azide complexes are explosive in nature, as indicated by DTA experiments and impact sensitivity measurements. Special precautions have to be taken during the synthesis and characterization of these materials. Small quantities of up to 1 g can be prepared without any explosion. Special mention should be made of the nickel hydrazine azide complex, which is prepared from NiCli + NaNa-I-2N2H4 H2O. The product is highly friction sensitive, especially in dry state, and so samples are to be handled with a Teflon spatula. A few milligrams are used for DTA and impact sensitivity tests. 

Note During the investigation of various methods of preparation, it was observed by Barlot (Ref 2) that if solns of equimolecular amounts of nickel nitrate and hydrazine nitrate are mixed no precipitation is observed. If, however, some hydrazine, or ammonia is added, an immediate precipitation of pink complex is observed... 

H. Ellern D.E. Olander, "Spontaneous Explosion of a Normally Stable Complex Salt , JChemEduc 32, 24(1955) [The salt which spontaneously exploded was pure Trihydrazinenickel(II) nitrate prepd by adding an ethanolic soln of nickelous nitrate, slowly and with agitation, to a 40% ethanolic soln of hydrazine hydrate. The pptd fine pink pdr was separated, washed with ethanol and then dried for 16 hrs in... 

The explosive properties of a series of 5 amminecobalt(III) azides were examined in detail. Compounds were hexaamminecobalt triazide, pentaammineazidocobalt diazide, cis- and traw.v-tetraamminediazidocobalt azide, triamminecobalt triazide [1], A variety of hydrazine complexed azides and chloroazides of divalent metals have been prepared. Those of iron, manganese and copper could not be isolated cobalt, nickel, cadmium and zinc gave products stable at room temperature but more or less explosive on heating [2]. Some polyammine azido-metal nitrates of Cr, Ni and Cu were found to be explosively photosensitive. Replacement of ammonia by triethanolamine gave compounds smoothly photodecomposing [3]. 

Detailed preparation methods for NHN and CoHN have been described by Chhabra et al. [20]. They used diluted aqueous solutions (4 and 8 %) of nickel nitrate preheated to 65 °C and simultaneously mixed it with a concentrated solution (>80 %) of hydrazine hydrate. The reaction gave a 90 % yield of NHN. When using cobalt nitrate the yield was 85 % of CoHN. Reducing the temperature to 25 °C led to yields around 90 % for both complexes however, the products obtained at lower temperatures were amorphous and did not flow as well as the granular ones produced at higher temperatures. 

Transition metal perchlorate, nitrate, and azide hydrazines are explosives. They are sensitive to friction and impact. Nickel perchlorate hydrazine is reported to be explosive even under water. Metal hydrazine complexes of azide and nitrate are highly sensitive to impact and friction and so decompose violently. Table 6.5 summarizes the impact sensitivities of these complexes as determined by the drop weight method [9]. 

Metal hydrazine complexes of azide and nitrate have been investigated as initiators. For example, the synthesis of nickel nitrate hydrazine [Ni (N03)2(N2H4)2] described in Chapter 3 has been commercially developed for use as detonators (blasting caps) in China. 

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