Industrial processes Ostwald process

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. 

PROBLEM 13.6 Nitric oxide reacts with oxygen to give nitrogen dioxide, an important reaction in the Ostwald process for the industrial synthesis of nitric acid ... 

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 ... 

Catalysis refers to the phenomenon by which the rate of a chemical reaction is accelerated by a snbstance (the catalyst) not appreciably consnmed in the process. The term catalysis was coined by Berzelins in 1835 and scientifically defined by Ostwald in 1895, but applications based on catalysis can be traced back to thousands of years ago with the discovery of fermentation to produce wine and beer. Nowadays, catalysts are used in 80% of all chemical industrial processes, and create annual global sales of about 1500 billion dollars and contribute directly or indirectly to approximately 35% of the world s GDP. Catalysis is central to a myriad of applications, including the manufacture of commodity, fine, specialty, petro-, and agro- chemicals as well as the production of pharmaceuticals, cosmetics, foods, and polymers. Catalysis is also an important component in new processes for the generation of clean energy, and in the protection of the enviromnent both by abating environmental pollutants and by providing alternative cleaner chemical synthetic procedures. 

Nitric acid, a widely used industrial and laboratory acid, is produced by the three-step Ostwald process. The oxidation number of nitrogen in HNO3 is +5. 

Ostwald process An industrial process that produces oxide and nitric acid from ammonia and oxygen. 

Nitric acid is one of the most important inorganic acids. It is used in the production of fertilizers, dyes, drugs, and explosives. The major industrial method of producing nitric acid is the Ostwald process. The starting materials, ammonia and molecular oxygen, are heated in the presence of a platinum-rhodium catalyst (Figure 13.22) to about 800°C ... 

Wilhelm Ostwald (1853-1932). German chemist. Ostwald made important contributions to chemical kinetics, thermodynamics, and electrochemistry. He developed the industrial process for preparing nitric acid that now bears his name. He received the Nobel Prize in Chemistry in 1909. 

Nitric acid, a major industrial and laboratory acid, is produced commercially by the multistep Ostwald process, which begins with the oxidation of ammonia ... 

The Ostwald process is a series of three reactions used for the industrial production of nitric acid from ammonia. 

In 1909, Ostwald was awarded the Nobel Prize in chemistry for his work in catalysis. My suspicion is that the committee decided to award him the prize - he was the "Mr. Physical Chemistry" of his day -and they chose his work in catalysis as providing as good a basis as any other. In fact, not much of his career had been devoted to catalysis. In 1884, he reported a study of the acid-catalyzed hydrolysis of methyl acetate which introduced kinetics, in the modern sense, into catalysis. He also tied the concept of catalytic activity to rate. Both of these items were important. Then in 1901-1904 he and his former student, Brauer, developed the Ostwald process for the oxidation on platinum of ammonia to nitric oxide. The first plant went on stream in Bochum in 1906 at a level of 300 kg of nitric acid per day. In 1908, the production was 3000 kg per day. The process actually goes back to Kuhlmann in 1838, but there had been no industrial interest in such a process, because Chili saltpeter was cheaper source of nitric acid than ammonia. However, at the beginning of the twentieth century, the ease with which the British fleet could sever the sea lane between Chili and Germany had become a stimulus to the development of the Ostwald process. 

Nitric acid is an important industrial chemical (see Box 15.8) and is manufactured on a large scale in the Ostwald process, which is closely tied to NH3 production in the Haber-Bosch... 

Ostwald process An industrial process used to make nitric acid from ammonia. The NHj is catalytically oxidized by O2 to form NO NO in air is oxidized to N O2 HN O3 is formed in a disproportionation reaction when N O2 dissolves in water. (Section 22.7)... 

Industrially, nitric acid is produced by the Ostwald process represented by the following equations ... 

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