Pyrotechnic copper powder

Some of the best blue flames are obtained from compositions based on potassium perchlorate, cuprous chloride, hexachloroethane, polyisobutylene, pyrotechnic copper powder and cellulose dust. 

The main species responsible for the blue flame from such a composition is cuprous chloride, CuCI hence the use of this salt together with the chlorine producer (hexachloroethane) and a source of extra copper (pyrotechnic copper powder). The cellulose dust acts as a moderator to control the burning rate of the pressed composition. 

Polynitropolyphenylene (PNP) (159), which is a polymeric explosive, exhibits high thermal stability and possesses a low sensitivity to friction and impact. This polymeric mixture, synthesized from the reaction of styphnyl chloride (106) with copper powder in nitrobenzene, has found use as a thermally stable binder in pyrotechnic compositions. ... 

Other industrial uses of aluminum flake include the building industry (production of aerated concrete) and the chemical industry (e.g., production of titanium dioxide, pyrotechnics, and explosives). Copper powder in flake form is used in the chemical industry (e.g., for phthalocyanine production, for lubricants). 

Butters, "Naval Pyrotechnic Formulas , NOLM (Naval Ordnance Laboratory Memorandum) 9292 (1947), Washington 25, DC (Naval Signal Cartridge MK3, Formula 2 Copper dust 1.9, Ba nitrate 67.2, hexachlorobenzene 14.7 Mg powder 14.7 linseed oil 1.5%. Burns 5 sec with green light at altitude 250 ft)... 

Copper-II-oxide forms a black to dark brownish-black amorphous or crystalline powder. The powder is insoluble in water and most organic solvents, but soluble in ammonia solution, acids and alkalies. The powder, after being roasted at high temperature for sometime, may become resistant to acids. Copper-II-oxide is widely used in the manufacture of fireworks and other pyrotechnic compositions for imparting a blue flame. 

To prepare copper-II-oxide, all you need to do is place the dried mass of hydrated copper hydroxides (prepared in step 1) into a crucible and then heat at 600 to 800 Celsius using a typical Bunsen burner for about 3 to 4 hours. During the heating process, water is volatized and removed, and the copper hydroxides are oxidized to copper-II-oxide forming a black powder. After the roasting process, the copper-II-oxide is cooled, and then stored in any suitable container. This copper-II-oxide can be used in pyrotechnic compositions, or used as a catalyst for the oxidation of various gases, such as the oxidation of methanol to formaldehyde. 

Copper-I-chloride forms a white crystalline powder, which is stable in dry air, but tends to turn yellow, green, blue, or brown on exposure to moisture, air, and light. Store dry in airtight amber glass bottles. The dry crystals have a melting point of 430 Celsius. The crystals are relatively insoluble in water, with partial decomposition, but are soluble in concentrated hydrochloric acid, and ammonia solutions. Copper-I-chloride can be used in pyrotechnic compositions, for imparting cool effects to the flames. Copper-I-chloride is a very useful catalyst for use in chemistiy. 

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