Nitric acid Ostwald process

Haber process nitrogen fixation nitrogen-fixing bacteria denitrification nitrogen cycle ammonia hydrazine nitric acid Ostwald process... 

The oxidation of ammonia to nitrous gases is a fast high-temperature reaction for the production of nitric acid (Ostwald process). The Claus process is an important petrochemical process for obtaining sulfur from H2S, which results from the desulfurization of petroleum and natural gas (hydrodesulfurization). One-third of the H2S is combusted to SO2, which reacts with the remaining H2S (see Table 8-1). 

The modem process for manufacturing nitric acid depends on the catalytic oxidation of NH3 over heated Pt to give NO in preference to other thermodynamically more favour products (p. 423). The reaction was first systematically studied in 1901 by W. Ostwald (Nobel Prize 1909) and by 1908 a commercial plant near Bochum. Germany, was producing 3 tonnes/day. However, significant expansion in production depended on the economical availability of synthetic ammonia by the Haber-Bosch process (p. 421). The reactions occurring, and the enthalpy changes per mole of N atoms at 25 C are ... 

Commercially, nitric acid is made by a three-step process developed by the German physical chemist Wilhelm Ostwald (1853-1932). The starting material is ammonia, which is burned in an excess of air at 900°C, using a platinum-rhodium catalyst ... 

H.20 The first stage in the production of nitric acid by the Ostwald process is the reaction of ammonia gas with oxygen gas, producing nitric oxide gas, NO, and liquid water. The nitric oxide further reacts with oxygen to produce nitrogen dioxide gas, which, when dissolved in water, produces nitric acid and nitric oxide. Write the three balanced equations that lead to the production of nitric acid. 

Nitric acid, HN03 (oxidation number +5) is used extensively in the production of fertilizers and explosives. It is made by the three-step Ostwald process ... 

C15-0098. The first step in the Ostwald process for the synthesis of nitric acid is the combustion of ammonia ... 

Ammonia is also the starting material for the production of nitric acid, and the first step is oxidation of ammonia by the Ostwald process. 

Nitric oxide (m.p. -163 °C, b.p. —152 °C) is an important compound primarily because it is a precursor of nitric acid that is prepared in the Ostwald process. 

Ostwald The basis of the modem family of processes for making nitric acid by the catalytic oxidation of ammonia. 

One of the steps in the Ostwald process for the production of nitric acid involves the oxidation of ammonia. 

Transition metals and their compounds are used as catalysts. Catalysts you may already know are Iron In the Haber process (Industrial production of ammonia) platinum in the Ostwald process (Industrial production of nitric acid) and platinum, rhodium and palladium In catalytic converters. 

Nitric acid (HNO ) is an important commercial chemical and was manufactured commercially to produce fertilizers and explosives as well as plastics and many other products. In 1902 a German chemist, WiUrehn Ostwald (1853—1932), developed a process wherein at high temperatures he used platinum catalysts to convert ammonia into nitric acid. When nitric acid is reacted with glycerol, the result is nitroglycerine—an unstable explosive unless dissolved in inert material, such as clay. It can then be stabihzed as dynamite. 

Currently, nitric acid is manufactured exclusively by catalytic oxidation of ammonia. Platinum or platinum-rhodium is an effective catalyst of this oxidation (Ostwald process). Three basic steps in such ammonia oxidation process are (1) oxidation of ammonia to form nitric oxide ... 

Platinum also is used extensively as a catalyst in hydrogenation, dehydrogenation, oxidation, isomerization, carbonylation, and hydrocracking. Also, it is used in organic synthesis and petroleum refining. Like palladium, platinum also exhibits remarkable abdity to absorb hydrogen. An important application of platinum is in the catalytic oxidation of ammonia in Ostwald s process in the manufacture of nitric acid. Platinum is installed in the catalytic converters in automobile engines for pollution control. 

The Germans need to supplant Chilean saltpeter supply, which could be cut off by enemy blockades, led to the search for methods to synthesize nitrates. The reaction required a supply of ammonia, which was economically synthesized by Fritz Haber (1868—1934) before World War I (see Ammonia). Ammonia could then be converted to nitric acid through the Ostwald process and then nitric acid can be reacted with bases to produce nitrates (see Nitric Acid) KOH + HNO 4 - KNO. + HO... 

Determine the values of AH° and AS° for each stage of the Ostwald process for the production of nitric acid. Predict the conditions of pressure and temperature that favor the formation of the products in each case. 

Ostwald process The production of nitric acid by the catalytic oxidation of ammonia, overall order The sum of the powers to which individual concentrations are raised in the rate law of a reaction. Example If the rate = [S02][S03]" l/2, then the overall order is f. 

PROBLEM 8.16 Use the information in Table 8.2 to calculate AH° (in kilojoules) for the reaction of ammonia with 02 to yield nitric oxide (NO) and H20(g)/ a steP m the Ostwald process for the commercial production of nitric acid. 

NH3 + 5 02 > 4 NO + 6 H20 Pt and Rh First step in the Ostwald process for synthesis of nitric acid HN03 Manufacture of explosives, fertilizers, plastics, dyes, lacquers... 

It is worth looking for a catalyst because the negative value of AG° indicates that the reaction is spontaneous under standard-state conditions. (This reaction is the first step in the Ostwald process for production of nitric acid. In industry, the reaction is carried out using a platinum-rhodium catalyst.)... 

Nitric acid is produced industrially by the multistep Ostwald process, which involves (1) air oxidation of ammonia to nitric oxide at about 850°C over a platinum-rhodium catalyst, (2) rapid oxidation of the nitric oxide to nitrogen dioxide, and (3) disproportionation of N02 in water ... 

Molecular nitrogen (N2) is unreactive because of its strong N=N triple bond. Nitrogen exhibits all oxidation states between —3 and +5. Nitric acid is manufactured by the Ostwald process. 

E. C. C. Baly and H. M. Duncan studied the decomposition of ammonia by means of a hot platinum wire. Two types of ammonia may be prepared—an inactive and an active modification—which are decomposed to different extents by the same quantity of energy. The active form is obtained by the slow withdrawal of ammonia from a cylinder containing the compressed gas by warming the cone. aq. soln. and drying the gas by quicklime and by isothermal evaporation of the liquefied gas at its b.p. The inactive form is obtained by the rapid evaporation of the liquefied gas. The inactive gas slowly recovers its activity on remaining in contact with the liquefied gas. The same effect can be produced by gently warming the gas by means of a platinum wire heated at 200°. In order to observe these phenomena, the platinum wire must be activated in the same way as is customary in W. Ostwald s process for the catalytic oxidation of ammonia in air to nitric acid. Alternatively,... 

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