Nitric acid, from ammonia oxidation

In the presence of catalyst, usually platinum, ammonia is oxidised by oxygen (and air) to nitrogen oxide. NO. This reaction, used to obtain nitric acid from ammonia (p. 238), can be demonstrated in the laboratory using the apparatus shown in Figure 9.4 the oxygen rate should be slow. 

The main use of rhodium is with platinum in catalysts for oxidation of automobile exhaust emissions. In the chemical industry, it is used in catalysts for the manufacture of ethanoic acid, in hydroformylation of alkenes and the synthesis of nitric acid from ammonia. Many applications of iridium rely on... 

Nitric acid was known to alchemists in ancient times. Cavendish in 1784 synthesized the acid by applying an electric spark to humid air. Earlier in 1776, Lavoisier determined that the acid contained oxygen. In 1798, Milner prepared nitric acid from ammonia along with nitrogen oxides by oxidation of ammonia vapor over red-hot manganese dioxide. In 1816, Gay-Lussac and Berthollet established its composition. 

Ever since England s Humphry Davy observed in the early 1800s that water was formed when hydrogen and oxygen react in the presence of a red-hot platinum wire, the phenomenon which Berzelius was to call catalysis has intrigued chemists. The uses of catalysts in industry were first consciously demonstrated by Peregrine Phillips in 1832 when he used platinum to oxidize sulfur dioxide (S02) to form sulfur trioxide (S03) and by Frederic Kuhlmann in 1837, when he produced nitric acid from ammonia. 

A process for the industrial production of nitrogen oxide and nitric acid from ammonia and oxygen. 

The Manufacture of Nitric Acid from Ammonia. Much nitric acid is made by the oxidation of ammonia. This oxidation occurs in several steps. Ammonia mixed with air burns on the surface of a platinum catalyst to form nitric oxide ... 

Nitric acid and the nitrates the manufacture of nitric acid from ammonia the fixation of nitrogen as nitric oxide the brown-ring test for nitrates. 

Fast reactions, in general, are conducive to obtain a large output from a relatively small volume of chemical processing equipment. For example, the ammonia oxidation reaction, which is the first stage of production of nitric acid from ammonia, is essentially complete in 3 x 10 " seconds at 750°C. This is sufficiently rapid so that the catalytic burner required to do this occupies only about the volume of a file cabinet drawer for the production of some 250 tonnes of nitric acid daily. Except for the cost of the catalyst inventory (which is platinum), the fabrication cost of the ammonia burner itself is relatively low. Follow-up reactions for the process are much slower than this so that the volume of equipment required to contain these parts of the process are much larger and more costly (Chap. 11). 

OTHER COMMENTS Platinum metal is used in the manufacture of apparatus used in laboratories and industries, including thermocouples, acid-proof containers, chemical reaction vessels, platinum resistance thermometers, electrodes, etc. has found applications in dentistry, electroplating industry, and in the jewelry industry soluble platinum salts have been used as catalysts in the production of high octane gasoline, vinylesters, petrochemicals, and pharmaceuticals platinum metals, as well as soluble platinum salts, have been employed as oxidation catalysts in the manufacture of sulfuric acid, nitric acid from ammonia, and acetic acid soluble platinum salts have been used and reused in the reclamation of platinum ore. 

OstwaM process An industrial process used to make nitric acid from ammonia. The NH3 is c t-alytically oxidized by O2 to form NO NO in air is oxidized to NO HNO3 is formed in a disproportionation reaction when NO2 dissolves in water. (Section 22.7)... 

Many times, the conversion of a reactor depends on the operating temperature. Even if isothermal operation is recommended, sometimes it is not easy to remove the energy generated during the reaction, or because it can be an asset for the process, the reactor operates under adiabatic conditions. The example that we are trying to solve now presents the features of this last type. In the production of nitric acid from ammonia, the converter oxidizes NHj into NO. The conversion of that reactor varies with temperature and the conversion profile may be obtained from experimental data in the Ullmann s Encyclopedia [9]. 

A basic problem for the production of nitric acid from ammonia can be found in [1,7]. However, typically dual processes have become preferred in order to take advantage of the physicochemical principles so that it is possible to enhance the conversion of ammonia oxidation at low pressure and improve the gases absorption downstream at a higher pressure. The problem that we address is presented as follows. The production of HNO3 fro ammonia starts with atmospheric air. The ratio between oxygen and ammonia to be fed to the converter must be 2.11, and the... 

The three nitrogen oxides NO, NO2, and NO3 are paramagnetic, odd-electron species. Both NO and NO2 are important in the synthesis of nitric acid from ammonia ... 

Eng 20, 470-477 (1919) (Description of ammonia oxidation process beginning with Kuhl-mann s method of 1839 and ending with the cyanamide process at Muscle Shoals) 7) C.L. Parsons, 1EC 11,541 (1919) (Oxidation of ammonia to nitric acid as well as the prepn of nitric acid from Chile saltpeter) 8) F.C. Zeis-berg, ChemMetEng 24, 443-45 (1921) (Manuf of nitric acid from Chilean saltpeter brief description) 9) G.B. Taylor, IEC 26,1217-19 (1922) (Some economic aspects of ammonia oxidation) 10) Ministry of Munitions, Manufacture of Nitric Acid from Nitre and Sulfuric Acid , London (1922) (Book No 7 of Technical Records of Explosives Supply, 1915—1919)... 

In the manufacture of nitric acid by the oxidation of ammonia, the first product is nitric oxide, which is then oxidized to nitrogen dioxide. From the standard reaction enthalpies... 

Chlorine dioxide Copper Fluorine Hydrazine Hydrocarbons (benzene, butane, propane, gasoline, turpentine, etc) Hydrocyanic acid Hydrofluoric acid, anhydrous (hydrogen fluoride) Hydrogen peroxide Ammonia, methane, phosphine or hydrogen sulphide Acetylene, hydrogen peroxide Isolate from everything Hydrogen peroxide, nitric acid, or any other oxidant Fluorine, chlorine, bromine, chromic acid, peroxide Nitric acid, alkalis Ammonia, aqueous or anhydrous Copper, chromium, iron, most metals or their salts, any flammable liquid, combustible materials, aniline, nitromethane... 

DeNOx (1) A Denox process for removing nitrogen oxides from the gaseous effluents from nitric acid plants. The oxides are reduced with ammonia, over a catalyst containing potassium chromate and ferric oxide. Developed by Didier Werke in the 1980s. 

Figure 1.4 also shows two other reactions. In reaction 2, ammonia reacts with water to form ammonium hydroxide. Reaction 3 shows that ammonia can also be oxidized to form nitric acid from which all forms of nitrates can be produced. All three forms of nitrogen (ammonia, ammonium hydroxide, and nitrates in various forms) are commonly found in soil and can be added to soil to supply nitrogen to plants (see also Figure 6.5). This process thus opened up an inexpensive method of producing nitrogen compounds that would be used as fertilizers.

In the DSN process, nitrogen tetroxide, N2O4 obtained from ammonia oxidation is absorbed by concentrated nitric acid in the presence of air or oxygen to yield pure nitric acid. Alternatively, N2O4 may be separated from the product gases of the ammonia oxidation process by refrigeration and then is treated with dilute nitric acid in air or oxygen. 

Nitrogen dioxide may be prepared by several methods. It is produced when an electric discharge is passed through air. It is made commercially from nitric oxide and air. Nitric oxide made by various processes (See Nitric Oxide) rapidly oxidizes to nitrogen dioxide. It is formed by decomposing nitric acid or by oxidizing ammonia with air ... 

For example, crotonaldehyde is listed in Table 1 as belonging in Group 19 (Aldehydes). The Chart shows that chemicals in this group should be segregated from sulfuric and nitric acids, caustics, ammonia, and all types of amines (aliphatic, alkanol, and aromatic). According to note A, crotonaldehyde is also incompatible with non-oxidizing mineral acids. 

Ammonium nitrate is the most readily available and cheapest salt of nitric acid, now manufactured wholly from synthetic ammonia and from nitric acid obtained by oxidation of ammonia. Ammonium nitrate was prepared for the first time as early as in 1659 by Glauber. The original experiments with it as a component of explosive mixtures began in the second half of the nineteenth century. Ammonium nitrate is the most widely used oxygen carrier, since it is an ingredient of the commonest group of high explosives. The reasons for this are to be seen in its properties and those of its explosive mixtures appreciable chemical stability, and low sensitiveness to friction and to shock. 

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