Nitric acid reactions

II [Anisole] = 2 x lo mol i" first-order reactions. For the experiment using pure nitric acid the half-life was about i min, but for that using fuming nitric acid reaction was complete in < 30 s. 

Tetryl. In the manufacture of Tetryl, it is usual not to nitrate dime thy laniline directly, but to dissolve it first in coned sulfuric acid and then to nitrate the dimethylaniline sulfate so obtained. Direct nitration of dimethylaniline proceeds so violently that it can be carried out only under specialized conditions. Many years experience of Tetryl manufacture has shown that the ratio of sulfuric acid to dimethylaniline should not be lower than 3 1, since a smaller amount of sulfuric acid may be detrimental to the nitration process. However, the ratio of sulfuric acid to dimethylaniline must not be too high, otherwise Tetryl yield is decreased. Temp must be maintained between 20-45° to avoid sulfonation of the benzene ring. Care must be exercised not to leave any unreacted dimethylaniline prior to introduction of nitric acid, because of the potential violence of the dimethyl-aniline-nitric acid reaction. Consequently, continuous methods of prepn are to be preferred as they inherently minimize accumulation of unreacted dimethylaniline... 

The presence of PSCs also leads to the removal of nitrogen oxides (NO and NO2) from the gas phase. As long as there are significant amounts of NO2 it will react with chlorine monoxide (CIO) to produce chlorine nitrate (reaction 11). This species subsequently reacts with HQ on PSC surfaces to produce nitric acid (reaction 13), which remains in the condensed phase. Also, nitric acid directly condenses with water to form nitric acid trihydrate particles, hence it is not available to regenerate NO2 by photochemical processes, as it does when it is in the gas phase. 

There is a synthesis, which is supposed to be safe and consists in using very small quantities of reagents and closely monitoring the temperature. However, the thermai control of the aromatic hydrocarbons/nitric acid reaction usually proves to be very difficult. Indeed, the temperature is either too high and the reaction is out of controi and can lead to detonation, or too low and the nitration or oxidation takes place too slowly causing the compounds to accumulate and the reaction to be delayed. The consequences are the same as before. 

Nitric oxide also can be made by reactions of nitric acid, nitrate, or nitrite salts with metals, metal oxides, or sulfates. Several metals react with nitric acid liberating nitric oxide. (See Nitric Acid, Reactions). For example, action of 1 1 nitric acid on copper turnings forms nitric oxide ... 

The final product of the action of nitric acid on hexamine or hexamine dinitrate is RDX see Vol 3, p C614. At low temps, however a number of other compounds are produced (Ref 2). Dilution of the hexamine dinitrate-nitric acid reaction mixture at low temperatures with ethyl ether and subsequent treatment of the gum so obtained with methyl and ethyl alcohols and water severally leads to l-alkoxy-3 5-dinitro-l 3 5-triazacyclohexane (IV), l 3-di-nitro-l 3 5-triaza-n-pentane 5-nitrate (V), and methylenedi-1 -(3 5-dinitro-1 3 5-triaza-cyclo-hexane) (VI). Dilution of the reaction mixture with methyl and ethyl alcohol produces mainly 3 5-dinitro-1 3 5-triazacyclohexane nitrate (II). 

Straight acetylene can be used as an explosive when in liquefied or solidified form (see Acetylene as an Explosive) (See also Acetylene Condensation or Polymerization Products, Acetylene Derivatives, Acetylene Hydroperoxides Peroxides, Acetylene-Nitric Acid Reactions, Acetylene Reactions, Acetylenic Compounds, Acetylides, Cuprene and Halogenated Acetylenes)... 

Gazz 60,172-84(1930) CA 24,3789 (1930) Note- More refs on acetylene derivatives are given under Acetylene-Nitric Acid Reaction Studies... 

Regarding the increased sensitiveness of the nitric-acid reaction with diphenylamine in water analyses, see R. Cimmino, Ztschr. anal. Chem., 38, 429 (1899) J. Chem. Soe., 70, II, 805 (1899). 

Also see Acetylene-Nitric Acid Reaction Studies, Vol 1,A67-R... 

N02. NH.CH2. N(N02).CH2. nh2. HN03, C2H8N607 mw 228.16 N 36.84% OB to C02 —7.01% cryst mp 129°, Sol in acet neutralized by aq Na hydroxide. Prepn is by diln of a hexamine dinitrate-nitric acid reaction mixt with eth at 0°, resulting in a gum. Evapn of the eth from the reaction mixt by addn of methanol with rapid stirring at RT, is then followed by recrystn of the resulting residue formed, after filtrn, with 80% nitric acid. The yield is 22%. Calcd power of the expl is 154% TNT (Ref 3) Refs 1) Beil, not found 2) K.W. Dunning ... 

In the methyl ether fractions of the spent acid and basic extract from the nitric acid reaction, illustrated in Figure 6, the methyl ethers of... 

In the methyl ester fraction of the spent acid from the nitric acid reaction (Figure 10), the methyl ether esters of p-hydroxybenzoic, vanillic, and syringic acids and the methyl esters of benzoic acid and the di- and tricarboxybenzenes have been found. These compounds are also present in the chromatogram of the basic extract, as are the methyl esters of the tetracarboxybenzenes and mellitic acid. In addition, dehydrodivanillic acid or pentacarboxybenzene or both are present in both chromatograms... 

N-Methyldipicrylamine. See 2,4,6,2, 4, 6 -Hexanitro-N-methyl-diphenylamine A440-R 3-Methyl-3-hydroperoxy-I-butyne. See under Acetylene Hydroperoxides A66-L 3-Methyl-3-hydroperoxy-l-pentyne. See under Acetylene Hydroperoxide A66-L o-Methylisoxazolecarboxylic Acid. See under Acetylene-Nitric Acid Reaction Studies... 

Cadmium Phosphide Cd3P2 Nitric Acid. Reaction with concentrated acid is explosive.9... 

To handle the volume of solution (about 30,000 L) necessary in the plant operation, a semi-batch denitration was necessary. Slow evaporation during product accumulation reduced the volume to <12,000 L, but increased the nitric acid concentration to about 11M. Experiments indicated that for a semi-batch denitration mode, a projected nitric acid concentration of 2M was an excellent stopping point, because no residual formic acid remains through the reflux and evaporation steps. Additional high nitric acid solution can then be added to the evaporated-denitrated solution without auto-initiation of a formic acid-nitric acid reaction. After all the Am-bearing solution had been transferred to the denitration evaporator and denitrated to <2M, the solution could be evaporated to 2500 L and denitrated to a residual free-acid concentration of 0.5 to 0.8M. In actual practice, the final 2500 L of solution was denitrated to 0.25M HNO3. 

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