N-butyl nitrate

Photolytic. Major products reported from the photooxidation of butane with nitrogen oxides under atmospheric conditions were acetaldehyde, formaldehyde, and 2-butanone. Minor products included peroxyacyl nitrates and methyl, ethyl and propyl nitrates, carbon monoxide, and carbon dioxide. Biacetyl, tert-butyl nitrate, ethanol, and acetone were reported as trace products (Altshuller, 1983 Bufalini et al, 1971). The amount of sec-butyl nitrate formed was about twice that of n-butyl nitrate. 2-Butanone was the major photooxidation product with a yield of 37% (Evmorfopoulos and Glavas, 1998). Irradiation of butane in the presence of chlorine yielded carbon monoxide, carbon dioxide, hydroperoxides, peroxyacid, and other carbonyl compounds (Hanst and Gay, 1983). Nitrous acid vapor and butane in a smog chamber were irradiated with UV light. Major oxidation products identified included 2-butanone, acetaldehyde, and butanal. Minor products included peroxyacetyl nitrate, methyl nitrate, and unidentified compounds (Cox et al., 1981). 

More recently, Polish chemists have reported a synthesis of both aryl and aliphatic secondary nitramines by treating amine substrates with ethyl magnesium bromide followed by reaction with n-butyl nitrate (Equation 5.8). This method, which uses nonpolar solvents like hexane or benzene, has been used to synthesize aliphatic secondary nitramines, and At-nitro-A-methylanilines which otherwise undergo facile Bamberger rearrangement in the presence of acid. The direct nitration of At-unsubstituted arylamines usually requires the presence of an electron-withdrawing group. Reactions are retarded and yields are low for sterically hindered amines. 

As early as 1929 Plyler and Steele [10] began an investigation of the infra-red spectra of nitric esters in the range methyl to n-butyl nitrates. Dadieu, Jele and Kohlrausch [11] studied the Raman spectra of nitric esters as well as inorganic nitrates, and aliphatic and aromatic nitro compounds. 

Reductive hydrolysis of n-butyl nitrate in an aqueous solution of ethyl alcohol in the presence of sodium hydrosulphide or ammonium hydrosulphide has been carried out by Merrow, Cristol and van Dolah [41], This is a complicated chemical reaction. As the result of hydrolysing the nitrate in the presence of sodium hydro-sulphide (the alkalinity of the solution corresponds to pH 10-11) 93% of nitrite ions and 7% of ammonia are obtained from the ester group nitrogen. When ammonium hydrosulphide is used, the nitrite ions initially produced rise to a maximum concentration and then fall to zero owing to the reducing action of the ammonium hydrosulphide. The reduction process takes place more effectively when the pH is above 10. 

In the investigation with n-butyl nitrate by Merrow, van Dolah and Cristol [41] already cited, neither the presence of the nitrate ion nor of mercaptan was detected. For this reason the following reaction mechanism was proposed for the hydrolysis of nitric acid alcohol esters by means of hydrosulphide ... 

The solid superacidic Nafion-Hhas also been found to catalyze effectively nitration reactions with various reagents.503 The nitrating agents employed were n-butyl nitrate, acetone cyanohydrin nitrate, and fuming nitric acid. In nitric acid nitrations, sulfuric acid can be substituted by Nafion-H and the water formed is azeotropically removed during the reaction (azeotropic nitration).503... 

Reaction of a primary aliphatic amine, n-butylamine, with nitronium tetrafluoroborate in methylene chloride or acetonitrile produced not n-butylnitramine, but n-butyl nitrate in about 20% yield. However, treating an electronegatively substituted primary aromatic amine, picramide, with nitronium tetrafluoroborate did give the primary nitramine, N,2,4,6-tetra-nitroaniline, in 85% yield. Olah (16) had reported previously that aniline was oxidized vigorously by nitronium salts. 

Benzene was converted to nitrobenzene in 80% selectivity at 40% conversion by passing benzene and concentrated nitric acid through a reactor containing an H-Y catalyst at 170°C. 3 The liquid phase nitration of benzene has been accomplished by heating a mixture of benzene and n-butyl nitrate at 80°C in the presence of... 

Nitration of chlorobenzene with n-butyl nitrate and a Nafion-H catalyst gave only a 15% yield of the chloronitrobenzenes but with acetone cyanohydrin nitrate a 49% yield was obtained with the para isomer produced with 70% selectivity.65 Using an iron exchanged montmorillonite to promote the nitration of chlorobenzene with nitric acid and acetic anhydride gave a 90% yield of the nitro chlorobenzenes in 15 minutes at 80°C. The para isomer was produced in 92% selectivity (Eqn. 22.28).68... 

Olah [40c] has drawn attention to the fact that the first solid acid catalyst was suggested by Kameo, Nishimura and Manabe (71 ]. They used polystyrene-sulphonic acid with nitric acid, but the system was unstable, as the catalyst was degraded by the strong acid. Olah and associates [72] developed a nitrating agent from n-butyl nitrate and acetone cyanohydrine nitrate by adding a per-... 

Table VIII. Nitration of Aromaticn with n-Butyl Nitrate o er Nation-H CatalyM...

Fig. 2.31 Deconstruction/damage of n-butyl nitrate for brick structure buildings, a before explosion, b in explosion, c after explosion...

Figure 2.31 indicates that the damage of n-butyl nitrate to brick structure building is very clear/obvious. When t+/T > 10, the damage of air shock waves to building is determined by the super pressure of shock waves. 

Besides the UV spectroscopy of nitrate esters [20], researchers [21] have studied infrared absorption characteristics of a series of nitrate esters from methyl nitrate to n-butyl nitrate. Raman spectroscopy of nitrate esters and nitro compounds of aliphatic or aromatic nitrate has been investigated [22]. 

The conventional preparation method of n-butyl nitrate is to nitrate n-butanol by the mixed acid of nitric acid and sulfuric acid. However, the yield is very low by this... 

As shown in Fig. 5.7, the differences between the preparation of -butyl nitrate and the other monobasic alcohol nitrates are evident (1) The nitration process for the other nitrate esters, such as methyl nitrate, is the continuous nitration-distillation method, while for n-butyl nitrate, the process is the reflux and water segregator method (2) In the washing process, n-butyl nitrate is washed by saturated sodium chloride solution because its density is close to that of water. 

The key device in the preparation of n-butyl nitrate is the water segregator, which is seldom used in chemistiy. The segregator is particularly designed in application of the preparation of n-butyl nitrate based on the requirements and working condition. The production facilities of n-butyl nitrate are shown in Fig. 5.8. 

The volume of the nitration reactor is about 110 L equipped with an explosion proof motor, a cycloidal reducer, mechanical seals, an anchor agitator, a temperature sensor, a pressure gauge, three feeding holes with different size, a segregator with a glass mirror, 1,000 mm condenser, and a jacket of heat transfer oil. The system also includes a temperature controller, an agitation controller, and a washing vessel. By application of the production unit, the yield of n-butyl nitrate is up to 95.7 % with the purity of 98.88 %. 

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