Ammonia-perchloric acid

When large spherical AP particles dg = 3 mm) are added, large flamelets are formed in the dark zone.Pl Close inspection of the AP particles at the burning surface reveals that a transparent bluish flame of low luminosity is formed above each AP particle. These are ammonia/perchloric acid flames, the products of which are oxidizer-rich, as are also observed for AP composite propellants at low pressures, as shown in Fig. 7.5. The bluish flame is generated a short distance from the AP particle and has a temperature of up to 1300 K. Surrounding the bluish flame, a yellowish luminous flame stream is formed. This yellowish flame is produced by in-terdiffusion of the gaseous decomposition products of the AP and the double-base matrix. Since the decomposition gas of the base matrix is fuel-rich and the temperature in the dark zone is about 1500 K, the interdiffusion of the products of the AP and the matrix shifts the relative amounts towards the stoichiometric ratio, resulting in increased reaction rate and flame temperature. The flame structure of an AP-CMDB propellant is illustrated in Fig. 8.1. 

Figure 8. Pressure dependence of reaction times of ammonia-perchloric acid...

Figure 11. Pressure dependence of burning rate predicted by the granular diffusion flame theory for the case (1) where premixed ammonia/perchloric acid flame is distended and (2) where it is collapsed...

IMG. 129. Diffusion flame model for ammonium perchlorate composite pro pcllanls according to Stemz and Summerficid (23). A/PA and O/F are ammonia perchloric acid and oxidant/fuel respectively. 

Hydrogen chloride Acetic anhydride, aluminum, 2-aminoethanol, ammonia, chlorosulfonic acid, ethylenediamine, fluorine, metal acetylides and carbides, oleum, perchloric acid, potassium permanganate, sodium, sulfuric acid... 

Pollution Prevention. Procedures haven been developed for recovery of composite ammonium perchlorate propellant from rocket motors, and the treatment of scrap and recovered propellant to reclaim ingredients. These include the use of high pressure water jets or compounds such as ammonia, which form fluids under pressure at elevated temperature, to remove the propellant from the motor, extraction of the ammonium perchlorate with solvents such as water or ammonia as a critical fluid, recrystalli2ation of the perchlorate and reuse in composite propellant or in slurry explosives or conversion to perchloric acid (166,167). 

A newer approach developed for producing commercial quantities of high purity AP (8,36) involves the electrolytic conversion of chloric acid [7790-93 ] to perchloric acid, which is neutralized by using ammonia gas ... 

Ammonia, hydrochloric acid, and sodium perchlorate are mixed and the reaction mixture crystallised in a vacuum-cooled crystalliser. Ammonium perchlorate crystals are centrifuged, reslurried, recentrifuged, and then dried and blended for shipment. Mother Hquor is evaporated to precipitate sodium chloride and the depleted mother Hquor is recycled to the reactor. The AP product made by this method is 99% pure and meets the specifications for propeUant-grade ammonium perchlorate. The impurities are ammonium chloride, sodium perchlorate, ammonium chlorate, and water insolubles. 

Extremely high purity ammonium perchlorate can be made by the direct reaction of ammonia and pure perchloric acid solution (8,36) ... 

Reagents such as water, ammonia, hydrochloric acid, nitric acid, perchloric acid, and sulfuric acid can be purified via distillation (preferably under reduced pressure and particularly with perchloric acid) using an allglass still. Isothermal distillation is convenient for ammonia a beaker containing concentrated ammonia is placed alongside a beaker of distilled water for several days in an empty desiccator so that some of the ammonia distils over into the water. The redistilled ammonia should be kept in polyethylene or parafrin-waxed bottles. Hydrochloric acid can be purified in the same way. To ensure the absence of metal contaminants from some salts (e.g. ammonium acetate), it may be more expedient to synthesise the salts using distilled components rather than to attempt to purify the salts themselves. 

A considerable amount of research has been conducted on the decomposition and deflagration of ammonium perchlorate with and without additives. The normal thermal decomposition of pure ammonium perchlorate involves, simultaneously, an endothermic dissociative sublimation of the mosaic crystals to gaseous perchloric acid and ammonia and an exothermic solid-phase decomposition of the intermosaic material. Although not much is presently known about the nature of the solid-phase reactions, investigations at subatmospheric and atmospheric pressures have provided some information on possible mechanisms. When ammonium perchlorate is heated, there are three competing reactions which can be defined (1) the low-temperature reaction, (2) the high-temperature reaction, and (3) sublimation (B9). 

Microscopic examination has shown [102,922] that the compact nuclei, comprised of residual material [211], grow in three dimensions and that the rate of interface advance with time is constant [922]. These observations are important in interpreting the geometric significance of the obedience to the Avrami—Erofe ev equation [eqn. (6)] [59,923]. The rate of the low temperature decomposition of AP is influenced by the particle ageing [924] and irradiation [45], the presence of gaseous products [924], ammonia [120], perchloric acid [120] and additives [59]. 

Note The TDM reagent can be used everywhere, where o-tolidine is employed. It can also be used on chromatograms, that have already been treated with ninhydrin, Pauly or ammonia perchlorate reagent or with iodine vapor [1]. Water may be used in place of 80% 2-propanol when making up solutions II, III and IV. The chlorine gas atmosphere in the chromatography chamber can also be created by pouring 5 ml hydrochloric acid (ca. 20%) onto 0.5 g potassium permanganate in a beaker such a chlorine chamber is ready for use after 2 min. 

Identify the major species in each of the following aqueous solutions (a) Na CH3 CO2 (sodium acetate) (b) HCIO4 (perchloric acid) (c) Cg Hi 2 Og (glucose, used for intravenous feeding) and (d) NH3 (ammonia, used for household cleaning). 

C16-0033. What are the major species present in each of the following solutions (a) 1.00 M perchloric acid (b) 0.25 M ammonia (c) 0.50 M potassium hydrogen carbonate and (d) 0.010 M hypochlorous acid, HCIO... 

Silverman and Dodson made the first detailed isotopic study of this exchange system using the separation afforded by the addition of 2,2 -dipyridyl at pH 5, followed by the precipitation of the ferric iron with either ammonia or 8-hydro-xyquinoline. Dodson , using this separation method, had previously obtained an overall rate coefficient of 16 l.mole" sec at 23 °C for 0.4 M perchloric acid media. The exchange in perchlorate and perchlorate-chloride media was found to conform to a rate law, first order with respect to both total ferrous and ferric ion concentrations, with an observed rate constant (k bs) dependent on the hydrogen-ion concentration, viz. 

The burning mechanism of composite propellants differs from that described above. There is no exothermic reaction which can lead to a self-sustaining fizz zone. Instead, the first process appears to be the softening and breakdown of the organic binder/fuel which surrounds the ammonium perchlorate particles. Particles of propellant become detached and enter the flame. The binder is pyrolysed and the ammonium perchlorate broken down, initially to ammonia and perchloric acid. The main chemical reaction is thus in the gas phase, between the initial dissociation products. 

Armannsson [659] has described a procedure involving dithizone extraction and flame atomic absorption spectrometry for the determination of cadmium, zinc, lead, copper, nickel, cobalt, and silver in seawater. In this procedure 500 ml of seawater taken in a plastic container is exposed to a 1000 W mercury arc lamp for 5-15 h to break down metal organic complexes. The solution is adjusted to pH 8, and 10 ml of 0.2% dithizone in chloroform added. The 10 ml of chloroform is run off and after adjustment to pH 9.5 the aqueous phase is extracted with a further 10 ml of dithizone. The combined extracts are washed with 50 ml of dilute ammonia. To the organic phases is added 50 ml of 0.2 M-hydrochloric acid. The phases are separated and the aqueous portion washed with 5 ml of chloroform. The aqueous portion is evaporated to dryness and the residue dissolved in 5 ml of 2 M hydrochloric acid (solution A). Perchloric acid (3 ml) is added to the organic portion, evaporated to dryness, and a further 2 ml of 60% perchloric acid added to ensure that all organic matter has been... 

An interesting variant uses acyl- or aroyl-methylpyridinium salts with ammonia or an amine to produce dipyridiniumdihydropyridine salts (655). With aromatic aldehydes the dihydropyridines are produced directly or the intermediate (654) can be isolated and subsequently treated with perchloric acid (75LA849). With formaldehyde (giving dihydropyridines without a substituent in position 4), the 1,5-diketone can be isolated and cyclized by ammonia (75LA864). The dipyridinium salts (655) undergo some useful transformations they can be oxidized to pyridines (656), and these dipyridinium pyridine salts give... 

F. C. Mathers, and A. W. Kenney prepared perchloric acid by distilling a mixture of potassium perchlorate and sulphuric acid in a current of steam. H. H. Willard oxidized ammonium perchlorate with an excess of a mixture of nitric and hydrochloric acids. As a result, a mixture of perchloric, nitric, and hydrochloric acids is formed. The latter are expelled by heating the mixture on a hot plate until white fumes of perchloric acid begin to appear. No unoxidized ammonia should be present in the soln. An acid of a composition approximately HCIO4+2H2O, boiling at 203°, remains. 

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