Azides explosion risk

Lead Azide. The azides belong to a class of very few useflil explosive compounds that do not contain oxygen. Lead azide is the primary explosive used in military detonators in the United States, and has been intensively studied (see also Lead compounds). However, lead azide is being phased out as an ignition compound in commercial detonators by substances such as diazodinitrophenol (DDNP) or PETN-based mixtures because of health concerns over the lead content in the fumes and the explosion risks and environmental impact of the manufacturing process. 

An interesting study (85) explores the use of sodium azide as an oxidative agent instead of performic acid. The big advantage offered here is that the oxidation of cysteine to cysteic acid is effected concurrent with the hydrochloric acid hydrolysis. The authors claim that the presence of 0.2% (w/v) NaN3 in the HC1 digestion does not represent an explosion risk. Recoveries of cysteine as cysteic acid were typically —90% for pure proteins. 

Nitrogen triiodide (black unstable crystals) explodes at the shghtest touch when dry. When handled, it is kept wet with ether. It is too sensitive to be used as an explosive, because it cannot be stored, handled, or transported. Azides, such as lead azide and hydrazoic azide, are highly unstable. Lead azide is a severe explosion risk and should be handled under water it is also a primary detonating compound. Hydrazoic acid or hydrogen azide is a dangerous explosion risk when shocked or heated. Metal fulminates, such as mercury fulminate, explode readily when dry. They are used in the manufacture of caps and detonators for producing explosions. 

Flammability hazard when plant used to remove organic solvents explosion risk when sterilising plant with ethylene oxide or when processing samples containing azides (20). 

The activating effect of the azide makes the fluorine labile, so that there is a risk of excess azide incorporation when attempting preparation by nucleophilic substitution of bromofluorocarboxylates, giving more explosive products than anticipated. 

Darier Goudet (Ref 25) describe the prepn with a min risk of expln by effecting the reaction within the interstices of a porous absorbent material which is inert and maintains the expl crysts separate from each other. Taylor Rinkenbach (Ref 27) prepd Ag azide in the pure state, as white colloidal aggregates, by mixing fairly coned solns of AgNOj and NaNs. The colloidal prod was more stable and less sensitive than the crysts. Meissner (Ref 30) described an app for the prepn of Ag azide by a continuous process and Stettbacher (Ref 73) detailed a recent lab procedure for its prepn Explosive Properties ... 

Lead picrate is considered highly sensitive to mechanical impact and thermal stimuli [6]. The anhydride is more sensitive to mechanical stimuli than the hydrates. Impact sensitivity of anhydride is significantly higher than the sensitivity of mercury fulminate (4 cm/0.5 kg vs. 24 cm for MF) [7,8]. Handling of lead picrate anhydride represents the same level of risk as handling of lead styphnate. The ignition temperature is 281 °C (explosion takes place instantaneously or within 1 s) [7]. The formation of lead picrate by reaction of tetryl (which decomposes to picric acid) with lead azide is reported as a possible reason for the higher sensitivity of this mixture compared to pure LA [6]. 

The fact that most of these tetrazole side chain elements for Cephalosporins since years are now produced worldwide at a volume of several 100 t/a demonstrates that azide chemistry - whose evolution to commercial scale was originally a source for concern -has come of age. It is now also offered as a standard production process by manufacturers that have specialized on the safe handling of the risk potential, also in custom synthesis. The safety risks associated with the handling of azides should not be underestimated, however. Its toxicity and the latent hazard of formation of highly explosive hydrazoic acid intermediates require expertise and plants with specific safety features for the safe handling of azides. 

The easiest organic azide and smallest member of azidomethanes, CH3N3, was first prepared by O. Dimroth in 1905 by simple methylation of sodium azide with dimethyl sulfate. Methyl azide has been proven to be more explosive than originally reported (same accounts for ethyl azide). The much more hazardous diazidomethane, CH2(N3)2 and triazidomethane, CH(N3)3, are accessible by rather time-consuming slow reactions of dichloro/dibromomethane and tribromomethane with a polymeric ammonium azide reagent. Several reports on the potential risk when working with azides in dichlorometh-ane exist, and are attributed to the potential formation of diazidomethane (please see appropriate references cited in ref. °). 

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