Solubility of tetryl

The solubility of tetryl in other solvents based on the data of various authors, mainly those of C. A. Taylor and Rinkenbach [24] is tabulated below [21] ... 

The solubility of tetryl in various solvents is tabulated below. 

Tetryl, like RDX, is a solid at the temperatures in the hydrolysis reactor. For the neat tetryl in burster charges, the grain size depends on the extent to which the pressed explosive charges have been processed prior to being added to the hydrolysis reactor. The case of tetryl in tetrytol is quite different. TNT and tetryl are very similar chemically, so the solubility of tetryl in molten TNT is quite high (82 g/100 g TNT at 80°C [176°F] 149 g/100 g TNT at 100°C [212°F]) (Kaye and Herman, 1980). Tetryl in tetrytol is mostly dissolved in the TNT phase, so the rate of dissolution and subsequent reaction in the hydrolysis medium depends mainly on the TNT/tetryl droplet size and not on the particle size of the tetryl that was originally used to make the tetrytol. 

The fate of lead during energetics hydrolysis in the presence of picrate is not understood. Until more information becomes available on the speciation of lead and the solubility of lead picrate under the conditions of hydrolysis, the possibility of solid lead picrate formation cannot be dismissed. As a precautionary measure, lead-based propellants should be processed separately from tetryl and tetrytol, eliminating the possibility of lead picrate formation. 

The two studies, taken together, suggest that tetryl, not TNT, leads to the formation of picrate, since neither the LANL results nor the Holston results showed the formation of picrate in the absence of tetryl. If this is correct, the formation of lead picrate cannot occur when Composition B and M28 propellant are coprocessed, provided no tetryl contamination is present. The solubility of lead picrate in the reaction medium under consideration is not known. Because lead in solution at high pH is predominantly in the form of plumbite ion (HPb02), the concentration of free Pb2+ ions should be very low, and the solubility product of lead picrate would have to be exceedingly small for... 

The purification of tetryl aims at removing by-products such as tetranitro derivative (VII), substances insoluble in benzene and the spent acid occluded by the crystals. The product is washed with cold water and then treated with hot water. This brings about the conversion of compound (VII) to (VIII)—the latter is soluble in hot water. The tetryl is then dissolved in benzene and insoluble constituents removed by filtration. The resulting solution is washed with water until it is completely free from acid. Alternatively, tetryl may be dissolved in acetone, precipitated with water, and finally deacidified. 

Tetryl is virtually insoluble in water. It dissolves moderately well in concentrated mineral acids, but in spent acid its solubility is barely 0.3%. Conversely, concentrated nitric acid is a good solvent for tetryl. When a solution i i concentrated nitric acid is diluted slowly with water, for instance by placing it in a moist atmosphere, gradual precipitation of tetryl occurs. Tetryl dissolves very readily in acetone. 

The big difference between the two states of equilibrium is presumably accounted for by the formation of tetryl solvates with benzene at higher temperatures and their greater solubility in benzene. 

This test is based on the formation of AN on hydrolysis with a mineral acid. HMX and other nitramines, such as Tetryl and ammonium salts interfere. However, Tetryl may be removed before the test with benzene (solubility of RDX is only 0.05%) and ammonium salts with water... 

Preparation of Tetryl. Twenty grams of dimethylaniline is dissolved in 240 grams of concentrated sulfuric acid (d. 1.84), the temperature being kept below 25°, and the solution is allowed to run from a separatory funnel drop by drop into 160 grams of 80 per cent nitric acid (d. 1.46), previously warmed to 55° or 60°, while this is stirred continuously and kept at a temperature between 65° and 70°. The addition requires about an hour. After all has been added, the stirring is continued while the temperature of the mixture is maintained at 65° to 70°. The material is allowed to cool the solid matter is collected on an asbestos filter, washed with water, and boiled for an hour with 240 cc. of water while further water is added from time to time to replace that which boils away. The crude tetryl is filtered off, ground under water to pass a 150-mesh sieve, and boiled twice for 4 hours each time with 12 times its weight of water. The solid is dried and treated with benzene sufficient to dissolve all readily soluble material. The solution is filtered and allowed to evaporate spontaneously, and the residue is recrystal-... 

No m-nitrotetryl is produced if pure dimethylaniline is used in the usual process for the manufacture of tetryl. The amount of this impurity in the usual process depends upon the amount of monomethylaniline which may be present. A large excess of sulfuric acid tends toward the production of m-nitro compounds, but a reduction in the amount of sulfuric acid is not feasible for this increases the amount of benzene-insoluble material. m-Nitro-tetryl reacts with water, as TNA does the nitro group in the 3-position is replaced by hydroxyl, and m-hydroxytetryl or 2,4,6-trinitro-3-methylnitraminophenol, yellow crystals from water, m.p. 183°, is formed. This substance resembles picric acid and forms explosive salts. It is readily soluble in water, and... 

Picric acid, one of the breakdown products of tetryl, is soluble in water and is expected to leach through soil to groundwater in substantial amounts (Army 1987d). It is expected to dissociate in water, especially when present in low concentrations. Picric acid may also form complexes with metal ions in soil, causing some of the chemical to remain bound (Army 1987d). Picric acid that is bound to soil may- be transformed via photolysis if present at the soil surface (Army 1987d). 

Properties Yellowish, nearly white crystals. M. P. 128°. Explodes when heated to 235°. Sp. gr. 1.82. Soluble in nitroglycerine. Sensitivity to impact similar to, and sensitivity to friction somewhat greater than, that of Tetryl hut the shattering power is much greater for the Pentryl. The disruptive power of Pen-tryl as measured in the small Trauzl block is 30 per cent greater than that of TNT, 15 per cent greater than that of Tetryl, and 27 per cent greater than that of picric acid.5 Rate of detonation (d = 0.8) 5000 m/sec. 

Tetryl forms yellow crystals with a melting point of 132 Celsius—it explodes when heated to 180 Celsius. It is insoluble in water, but soluble in alcohol, benzene, and acetic acid. Solutions of tetryl in solvents should be stored in a dark place, protected from light—as they will slowly deteriorate on standing—normally tetryl is stored dry or moistened with kerosene or water. Solutions of tetryl or even the dry solid upon the skin and teeth causes yellow staining. Tetryl is a very powerful explosive used primarily in detonators as a booster for artillery, mortar, and projectile fuses. Tetryl is a standard military initiating explosive (booster). Tetryl boosters are common in shape charges, mines, mortars, artillery shells, rockets, anti-tank munitions, and missiles. 

Only a small amount of PA was observed in the solids formed during the tetrytol testing (O Neil, 2001). However, if a mixed feed stream containing an aromatic nitro compound (Composition B and tetryl or tetrytol) is processed with a propellant that contains lead, lead picrate (a very sensitive primary explosive) can be formed. During the M28 propellant tests, lead dioxide precipitated on the cell membrane, so it is possible that the precipitation of lead with the small amount of picric acid that might be present does not compete with the formation of lead dioxide in the electrochemical cell. However, the possibility of lead picrate precipitation cannot be dismissed a priori. A determination of the relative solubilities of lead dioxide and lead picrate in nitric acid solutions could provide some insight into whether the formation of lead picrate is likely to be a problem for mixed feeds. 

Tetryl dissolves readily In concentrated nitric acid and moderately well In other mineral adds but Is soluble to the extent of only 0.3 percent In the spent acid after manufacture. Table 8-27 lists tetryl solubility in various solvents at the temperatures given. Benzene holds more tetryl in solution if a solution with solid tetryl present Is cooled to a given temperature than if a mixture of benzene and an excess of tetryl is heated to and maintained at a given temperature. At 15°C, 25°C, 35°C, 45°C, and 55°C, tetryl has respective... 

Where the maintenance of a clear channel between sprue and the slowest freezing part of a charge is impractical, cavitation is avoided by casting charges in layers, each of which is allowed to crust over before pouring the next TNT melts at 81°. It forms eutectics with RDX, Tetryl (68°), PETN (76°), and other impurities in the mix and makes these materials more soluble at higher temps. Thus, there is a general tendency for the solid content and, hence, the apparent viscosity of most castable mixts to decrease as the temp is increased. However, a reversal of the tendency toward the reduction in viscosity has been noted in Comp B when it heated above 100°... 

Tetrytols are soluble in the same solvents that dissolve TNT and Tetryl. Solubility levels depend on the proportion of each constituent in the Tetrytol... 

Based on effects observed in water (Navy 1984b), tetryl released to soil is expected to be susceptible to slow hydrolysis in acidic and neutral soils and to relatively rapid hydrolysis in highly alkaline soils (HSDB 1994). Samples of water collected from lysimeters containing tetryl-contaminated soil indicated that the major transformation products were picric acid (5-14%) and other polar, water- soluble decomposition products no tetryl was detected in the water, or in the soil at the end of the study, suggesting complete hydrolysis (Kayser and Burlinson 1988 Navy 1982). The specific reaction leading to these products was not determined. Because tetryl is subject to photolysis in water, it may be susceptible to photolysis on sunlit soil surfaces (HSDB 1994). 

Purified surplus explosive can undergo large-scale commercial reuse in slurry explosives. Slurry explosives are a saturated aqueous solution of water-soluble oxidizer, which carries particles of oxidizer and sensitizing "fuel" in suspension. The most common oxidizer is ammonium nitrate, and the most common sensitizer is aluminum powder. Sodium nitrate, sodium perchlorate, and sodium chlorate are possible alternative oxidizers. Patent literature shows that munition explosives such as TNT, tetryl, HMX, RDX, and NG are used as sensitizers in slurry explosives. The reported consumption of slurry explosives is hundreds of millions of pounds annually. 

Among the booster explosives, we find trinitrophenylmethylnitramine, commonly called tetryl or tetralite. An outstanding example of an alkylated compound in the field of flavors is vanillin. Alkylation plays a striking part in the preparation of hypnotics, e.g., barbital (Veronal), pheno-barbital (Luminal), and Amytal, rendering them lipoid-soluble. 

Tetryl, also called tetranitromethylaniline, has a melting point of about 130°C with some decomposition. It is nonhygroscopic and practically insoluble in water but highly soluble in acetone and benzene. It can be stored for over 20 years at ambient temperatures with no noticeable change in properties. 

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