Abstract: This invention relates to an improved process for the recovery and regeneration of nitric acid from spent acid obtained from the mixed acid nitration of aromatic compounds. In that process a mixed acid of sulfuric acid and nitric acid is contacted with an aromatic composition at a temperature and pressure sufficient for producing a nitroaromatic composition and a spent acid containing unreacted nitric acid, sulfuric acid and solubilized nitroaromatic compounds in said spent acid. The improvement comprises initially heating the spent acid to a temperature of from about 120.degree. to 200.degree. C. for a time sufficient to convert said nitroaromatics in said spent acid to a nitroaromatic composition having a boiling point greater than 300.degree. C. at atmospheric pressure and then flash distilling the hot spent acid containing nitroaromatics compositions at a pressure from about 5 to 15 psia and temperature of 150.degree. to 200.degree. C.

Abstract: Sulphuric and nitric acids present in dinitrotoluene are separated from the dinitrotoluene by adding up to 10 wt. % water (based on quantity of dinitrotoluene) to the mixture of dinitrotoluene, sulphuric acid and nitric acid, mixing and separating the aqueous phase containing nitric and sulphuric acids. The mixtures treated by this process generally contain up to 5 wt. % nitric acid and up to 6 wt. % sulphuric acid.

Abstract: Aromatic nitration reactions and, more specifically, a process for nitrating toluene to dinitrotoluene. The process involves a liquid phase nitration reaction of anhydrous nitric acid and toluene in a molar ratio of between about 5:1 and about 9:1 of nitric acid to toluene in a reactor at a reaction temperature of between about 40.degree. C. and about 70.degree. C., in the absence of sulfuric acid and in the absence of any dipolar organic solvent, to produce a mixture containing dinitrotoluene, and isolating said dinitrotoluene by contacting said mixture with a phase separating effective amount of an alkali or alkaine earth metal nitrate salt to cause phase separation of said dinitrotoluene.

Abstract: Despite the instabity of perfluoralkyl anions, it is possible to perfluoroalkylate aromatic compounds if appropriately substituted by suitable electronegative substituents (e.g., nitro, trifluoromethylsulfonyl, etc.). Thus a novel Meisenheimer complex is formed by thermally decomposing a salt of a perfluoroalkanoic acid in the presence of an aromatic compound such as 1,3,5-trinitrobenzene. Oxidation with organic hypochlorite yields the corresponding perfluoroalkylated aromatic compound.

Abstract: This invention relates to the preparation of a mixture of nitroaromatic compositions, particularly a mixture of mononitrobenzene and dinitrotoluene. The conitration of a mixture of aromatic hydrocarbons is accomplished by contacting the mixture of hydrocarbons with nitric acid, in the absence of sulfuric acid, at temperatures of from about 40.degree. to 70.degree. C. By the use of nitric acid alone, one avoids the heterogeneous nitration associated with the use of sulfuric acid and thereby one can effectively produce a reaction mixture containing mononitrobenzene and dinitrotoluene.

Abstract: Para selectivity in the conversion of a monosubstituted benzene containing a meta-directing group to disubstituted benzenes can be substantially enhanced by carrying out the reaction in the gas phase with an inorganic or organic substitution agent in the presence of a catalyst composition comprising a crystalline molecular sieve material. In particular, nitrobenzene can be converted using nitrogen dioxide in the gas phase to a product containing an augmented proportion of para-dinitrobenzene using a wide range of catalyst compositions comprising both synthetic and naturally occurring crystalline molecular sieve materials such as ferrierites, X-type zeolites, Y-type zeolites, silicalite, framework-modified silicalites, ZSM aluminosilicates, AMS-1B borosilicates, and AlPO.sub.4 types.

Abstract: This invention comprises a process for separating the minor dinitrotoluene isomers, 2,3-dinitrotoluene and 3,4-dinitrotoluene from a feed mixture comprising 2,4- and 2,6-dinitrotoluene, and the minor isomers, which process comprises contacting the mixtures at adsorption conditions with an adsorbent comprising a Y type, or dealuminated Y type, zeolite, cation exchanged with Na, Ca or H, thereby selectively adsorbing the 2,3- and 3,4- isomers or 2,4- and 2-6 isomers, respectively. The remainder of the feed mixture is removed from the adsorbent and the minor isomers are recovered by desorption at desorption conditions with a desorbent material comprising an alcohol, ketone or an ester.

Abstract: In a method for denitrifying the nitric acid- and nitrous acid-containing spent acid phase from the nitration of an aromatic hydrocarbon by the mixed acid process which comprises forming a denitrification reaction medium by contacting the spent acid phase with an aromatic hydrocarbon under nitration reaction conditions to recover the nitric acid by the formation of a nitroaromatic hydrocarbon, the improvement which comprises(a) adding an amount of aromatic hydrocarbon which is slightly less than or equal to the stoichiometric amount necessary to deplete the spent acid phase of nitric acid,(b) photometrically monitoring the denitrification reaction medium for the appearance of a dark red to black color, and(c) upon detection of such color, adjusting the aromatic hydrocarbon:nitric acid molar ratio in the denitrification reaction medium to eliminate the color by reducing the aromatic hydrocarbon feed rate, or adding nitric acid to the denitrification reaction medium.

Abstract: This invention comprises a process for separating 2,4-dinitrotoluene from a feed mixture comprising 2,4-dinitrotoluene and at least one isomer thereof, which process comprises contacting the mixture at adsorption conditions with an adsorbent comprising an X or Y type zeolite cation exchanged with a cation in the group K, Na, Ca, Ba, Li or Mg, thereby selectively adsorbing the 2,4-dinitrotoluene. The remainder of the feed mixture is removed from the adsorbent and the 2,4-dinitrotoluene is recovered by desorption at desorption conditions with a desorbent material comprising a C.sub.3 to C.sub.5 alcohol, a ketone, toluene, an ester or a nitrocompound.

Abstract: The present invention relates to improvements in processes of preparing dinitrated aromatic compounds, particularly dinitrated aniline and dinitrated substituted aniline compounds, employing relatively dilute and then more concentrated nitric acid as the nitrating agent.

Abstract: Catalysts compositions useful to catalyze the nitration of aromatic compounds in the vapor phase to produce nitroaromatic compounds are represented by the empirical formula:(M.sup.1.sub.a M.sup.2.sub.b O.sub.c).sub.x (NO.sub.2).sub.ywherein M.sup.1 is at least one element selected from Group 4b of the Periodic Table of the Elements, M.sup.2 is at least one element selected from Group 3b of the Periodic Table of the Elements, a is 1, b is 0.050 to 20, c is a number taken to satisfy the average valences of M.sup.1 and M.sup.2 in the oxidation states in which they exist in the composition, x is 1, and y is 0 to c. The compositions are particularly effective to catalyze the vapor phase nitration of chlorobenzene and are characterized in such reaction by providing a para/ortho isomer distribution ratio of at least about 1.9/l.

Abstract: This invention relates to a process for removing nitrocresols and picric acid contaminants from a wastewater stream generated in the production of nitroaromatics, particularly dinitrotoluene, by the mixed acid technique. The process involves contacting the crude dinitrotoluene generated by the mixed acid technique with an alkaline medium to generate an alkaline wash water containing water soluble nitrocresols and picric acid therein. This wastewater is separated from the organic component and recycled for contact with further quantities of crude dinitrotoluene product from the reactor. When the concentration of the water soluble salts of nitrocresols and picric acid is of sufficient concentration the wash water is treated with aqueous acid in sufficient proportion to convert the water soluble salts to water insoluble organics. After treatment with acid, the organic material is separated from the wastewater and the organics incinerated.

Abstract: Monomethyl-substituted methylene compounds are obtained by reacting methylene compounds of the formula ##STR1## in which R.sup.1 and R.sup.2 independently of one another represent --CN, --CO--R.sup.3, --SO.sub.2 --R.sup.3 or --NO.sub.2 andR.sup.1 can additionally denote -aryl(R.sup.1).sub.n,whereinR.sup.3 denotes --OH, alkyl, aralkyl, aryl, alkoxy, aralkoxy or aryloxy, or amino which is substituted by alkyl and/or aralkyl and/or aryl, and furthermoretwo radicals R.sup.3 together can be an alkylene group, the radical of an aliphatic diol or of an aliphatic diamine or the group --NH--CO--NH-- and n represents 1, 2 or 3,with formaldehyde and with hydrogen in the presence of a condensation catalyst and a hydrogenation catalyst at elevated temperature, the methylene compound being introduced into the liquid phase of the mixture of reactants in the course of the reaction.

Abstract: A method is provided for denitrifying the aqueous spent acid of mononitration. The nitric acid in the aqueous spent acid is recovered by adiabatically reacting greater than a stoichiometric amount of a mononitroaromatic hydrocarbon with the aqueous spent acid which has been fortified to a nitric acid concentration of at least about 2 wt %. The denitrification method is useful in treating the aqueous spent acid phase from the mononitration stage of a dinitrotoluene process.

Abstract: An adsorptive separation process for separating the para-isomers of a di-substituted benzene from a feed mixture comprising the para-isomer and at least one other isomer. One substituted group is NO.sub.2 -- and the other group is a normal hydrocarbon having less than 6 carbon atoms per molecule, the halogens, NH.sub.2 --, NO.sub.2 -- or C.tbd.N--. The process comprises contacting the feed mixture with an adsorbent comprising crystalline silica having a silica/alumina mole ratio of at least 12, selectively adsorbing substantially all of the para-isomer to the substantial exclusion of the remaining isomers and thereafter recovering high-purity para-isomer by means of desorption with an appropriate desorbent material.

Abstract: Pentanitrotoluene is prepared by a method which comprises preparing an amdinitrotoluene from a precursor of either TNT or 2,5-dinitro-3-methylbenzoic acid, nitrating the aminodinitrotoluene to produce a nitramine intermediate, converting the nitramine intermediate to an aminotetranitrotoluene and oxidizing the aminotetranitrotoluene with peroxydisulfuric acid to pentanitrotoluene. Pentanitrotoluene is an explosive.

Abstract: Aromatic hydrocarbons are nitrated by reacting the aromatic hydrocarbon in a nitrogen tetroxide-containing liquid reaction medium, in the presence of a beta-dicarbonyl compound having a "W" configuration with a carbonyl group at each apex of the "W", preferably at a pressure and temperature sufficient to maintain the nitrogen tetroxide in the liquid state. Addition of an inert organic co-solvent to the liquid nitrogen tetroxide for the metal acetylacetonate promoted nitration of benzene essentially eliminates the production of dinitrobenzenes.

Abstract: A method for the N-denitration of secondary N,2,6-trinitroanilines with phase transfer catalysts.

Abstract: The invention relates to a method of eliminating or substantially reducing the amount of cyanide formed in a polynitroaromatic, e.g. dinitrotoluene process. The invention comprises removing the nitrophenolic material from the mononitroaromatic formed in a first stage nitration of toluene prior to feeding the mononitroaromatic to the subsequent nitration zones.

Abstract: 1,3,5-trinitrobenzene is produced through direct oxidation of 2,4,6-trinitrotoluene with nitric acid.

Abstract: The invention relates to a process for the preparation of nitrated aromatic compounds by the mixed acid process, in which water is removed from the reaction mass by passing an inert gas through it.

Abstract: In the nitration of a volatile aromatic compound wherein the compound is reacted with a liquid nitrating agent thereby to effect nitration and to produce a waste gas containing some of the aromatic compound, nitrogen oxides and nitric acid, the improvement which comprises contacting the waste gas with fresh nitrating agent thereby to remove the aromatic compound from the gas into the nitrating agent, and thereafter using such nitrating agent to effect subsequent nitration.

Abstract: A process has been developed for isolating aromatic dinitro compounds by using nitric acid in specified concentrations in different portions of a rectifying column and separating off the mixture of aromatic dinitro compounds from the sump of the rectifying column.

Abstract: Hexanitrobenzene is prepared by oxidizing the amine group of pentanitroaniline with H.sub.2 O.sub.2 in H.sub.2 SO.sub.4. The compound is a high density explosive.

Abstract: A polymer having aromatic or heterocyclic rings as the only structural elements said aromatic or heterocyclic rings containing at least two nitro groups is disclosed as well as a method of preparing the same. The polymers are useful as binding agents for thermo stable propellants and can be easily formed into films. They remain thermally stable up to temperatures of at least 200.degree. C.

Abstract: Substituted gem-dinitroalkanes are prepared by reacting a nitro olefin, tetranitromethane and an alcohol or organolithium derivative. The substituted gem-dinitroalkanes are useful as explosives, plasticizers and binders.

Abstract: Novel energetic sulfate salts which form a eutectic with ammonium nitrate ntaining explosive formulations are disclosed. The eutectic quality of such formulations facilitates melt loading thereof. Two typical novel sulfate salts of the invention are 1-(2-ammonium sulfatoethyl)-2,4,6-trinitrobenzene and 1,3-Bis-2(2-ammonium sulfoethyl)-2,4,6-trinitrobenzene. Also disclosed is a method for the synthesis of such sulfate salts together also with a method for the synthesis of the necessary alkanol substituted trinitrobenzene derivative precursor.

Abstract: The present invention relates to improvements in processes of preparing dinitrated .[.aromatic compounds, particularly dinitrated aniline and dinitrated substituted aniline compounds, employing relatively dilute and then more concentrated nitric acid as the nitrating agent.]. .Iadd.aniline and substituted phenol compounds in a two-step process, employing, in the first or mononitration step the spent nitric acid from the second of dinitration step. .Iaddend.