Ostwald process production rate

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. 

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. 

In a continuous flow reactor, these quantities will, of course, again depend on the external parameters pi and T, as will be illustrated in the following with the example of ammonia oxidation on a Ru02(1 10) surface [34]. This Ostwald process is the basis for large-scale production of nitric acid that operates with platinum-based catalysts at temperatures >1000K where the rate... 

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. 

Ostwald expanded Berzelius explanation by stating that catalysts were substances that accelerate the rate of chemical reactions without being consumed. In over 150 years since Berzelius work, catalysts have come to play a major economic role in the world market. In the United States alone, sales of process catalysts in 1996 were over 1 billion, the major uses being in petroleum refining and in chemical production. 

When I started making and using catalysts, I saw no reason for doubting the correctness of the Ostwald definition of a catalyst. You remember that he said a catalyst is a material which changes the rate of a chemical reaction without itself appearing in the products. In other words the catalyst is unchanged by the process. Since that time I have learned the shortcomings of that definition. In fact, I now refer to Industrial Catalysis" as "The Science of Dirty Surfaces."... 

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