Nitric acid, nitration

If phenol is heated with more concentrated nitric add (in the presence of sulphuric acid), nitration occurs ultimately at the para and at both the ortho positions, giving picric acid or 2,4,6-trinitrophenol. To prepare picric acid, however, it is more convenient first to heat the phenol with sulphuric acid, whereby a mixture of 0- and p-phenol sulphonic acids is readily obtained. If this mixture is now heated with concentrated nitric acid, nitration occurs at the... 

Picric acid, the 2 4 6-trinitro derivative of phenol, cannot be prepared in good yield by the action of nitric acid upon phenol since much of the latter is destroyed by oxidation and resinous products are also formed. It is more convenient to heat the phenol with concentrated sulphuric acid whereby a mixture of o- and p-phenolsulphonic acids is obtained upon treatment of the mixture with concentrated nitric acid, nitration occurs at the two positicsis mela to the —SOjH group in each compound, and finally, since sulphonation is reversible, the acid groups are replaced by a third iiitro group yielding picric acid in both cases ... 

Control of NO emissions from nitric acid and nitration operations is usually achieved by NO2 reduction to N2 and water using natural gas in a catalytic decomposer (123—126) (see Exhaust control, industrial). NO from nitric acid/nitration operations is also controlled by absorption in water to regenerate nitric acid. Modeling of such absorbers and the complexities of the NO —HNO —H2O system have been discussed (127). Other novel control methods have also been investigated (128—129). Vehicular emission control is treated elsewhere (see Exhaust control, automotive). 

Dinitration of toluene results in the formation of a number of isomeric products, and with a typical sulfuric—nitric acid nitrating mixture the following mixture ofisomers is obtained 75 wt % 2,4-dinitrotoluene [121-14-2] 19 wt % 2,6-dinitrotoluene [606-20-2], 2.5 wt % 3,4-dinitrotoluene [610-39-9], 1 wt %... 

Nitrochlorobenzene from chlorobenzene and nitric acid Nitration... 

Manufacture of pure products, such as sulfuric acid, nitric acid, nitrates, phosphates, adipic acid, and so on... 

Salpeter-sauresalz. n. salt of nitric acid, nitrate, -schaum, m. wall saltpeter (calcium nitrate efflorescence). 

Copper alloys Ammonia/amines Nitric acid/nitrate fumes... 

Examples Chlorine Hydrogen peroxide Nitric acid Nitrates Ozone Hypochlorites Examples Most organic and inorganic materials are not oxidizers Reducing agents... 

When benzo[a]pyrene adsorbed from the vapor phase onto coal fly ash, silica, and alumina was exposed to nitrogen dioxide, no reaction occurred. However, in the presence of nitric acid, nitrated compounds were produced (Yokley et al, 1985). Chlorination of benzo [a] pyrene in polluted humus poor lake water gave ll,12-dichlorobenzo[a]pyrene and 1,11,12-, 3,11,12- or 3,6,11-... 

The possibility of using nitric acid as an oxidizing agent in a leaching operation is often prohibitive because many reagents used in solvent extraction are not stable in an oxidizing solution. By the AX method, however, a nitric acid (nitrate) leach solution can be converted to a weak sulfuric acid (sulfate) solution, well suited for a solvent extraction treatment. 

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 ... 

Durham, J. L L. L. Spiller, and T. G. Ellestad, Nitric Acid-Nitrate Aerosol Measurements by a Diffusion Denuder A Performance Evaluation, Atmos. Environ., 21, 589-598 (1987). 

C(N02)2CH2C(N02)2CH3 crysts, mp 132°, d 1.70. Prepd from 2,2,4,6,6-pentanitroheptane K-salt N204 in CC14 at -15 to -25° for 4 hrs or by nitric acid nitration of the pentanitroheptane (Refs 4 5) also from MeNH2 dichlorotetra-nitroethane (Ref 2). Its hot bar ignition temp is 338° its sensitivity is approx that of pentolite (Refs 3 4)... 

Hydroxides. The generic name for compounds of the type Ma(OH) where M is a metal and a b are integers. Most hydroxides are insol or sparingly sol in water but are sol in aq acid with the formation of salts. Most hydroxides have been used in neutralizing nitrated explosives made by mxied acid or nitric acid nitration although bicarbonates are more commonly employed. The more common hydroxides are listed below ... 

N0CH2C0NHCH2CH20N02 mw 209.12, N 20.10%, OB -34.4% prepd by nitric acid nitration of N-2-hydroxyethylglycolamide, HOCH2CONHC2Hs OH. Claimed to be useful as a blasting cap charge... 

N.E. Gehrig, USP 3242019(1966) CA 64, 19310(1966) (Solid emulsion blasting agent comprising nitric acid, nitrates fuels. Division of USP 3164503 Disclosure is similar but claims are diff)... 

Denitration Removal of nitric acid, nitrates or nitrogen oxides from acids and other substances. 

Stable nitronium salts, which are readily prepared from nitric acid (or nitrates) with HF and BF3 (and other Lewis acids such as PF5, SbF5, etc.) [Eqs. (5.171) and (5.172)], will nitrate aromatics in organic solvents generally with close to quantitative yield. Because HF and PF5 (or BF3) can be easily recovered and recycled, the method can be considered as a nitric acid nitration using a superacid catalyst [Eq. (5.173)]. 

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... 

Nitric acid Nitrates Potassium nitrate (KN03)... 

Industrial fluid-fluid reactors may broadly be divided into gas-liquid and liquid-liquid reactors. Gas-liquid reactors typically may be used for the manufacture of pure products (such as sulfuric acid, nitric acid, nitrates, phosphates, adipic acid, and other chemicals) where all the gas and liquid react. They are also used in processes where gas-phase reactants are sparged into the reactor and the reaction takes place in the liquid phase (such as hydrogenation, halogenation, oxidation, nitration, alkylation, fermentation, oxidation of sludges, production of proteins, biochemical oxidations, and so on). Gas purification (in which relatively small amounts of impurities such as C02, CO, COS, S02, H2S, NO, and... 

Nitromorphine is given by direct nitric acid nitration of morphine(163) however, with nitric oxide, 2-nitromorphine results. These compounds may be elaborated further to amino derivatives and by diazomethane treatment to the corresponding codeines. Codeine with concentrated H2S04 at ambient temperature afforded the zwitterion 68, which in nitric acid gave 1 -nitrocodeine. A similar conversion was achieved with ethylcodeine and hydrocodone.<164)... 

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