Haber Process manufacture

This reaction is an undesirable side reaction in the manufacture of hydrogen but utilised as a means of removing traces of carbon monoxide left at the end of the second stage reaction. The gases are passed over a nickel catalyst at 450 K when traces of carbon monoxide form methane. (Methane does not poison the catalyst in the Haber process -carbon monoxide Joes.)... 

FIGURE 9.17 The Haber process is still used to produce almost all the ammonia manufactured in the world. This pie chart shows how the ammonia is used. The figures are percentages. Note that 80%— as shown by the green band—is used as fertilizer, either directly or after conversion into another compound. 

NH3. Ammonia is a colorless gas. It is a strong base, forms hydrogen bonds, is soluble in water, and is a fairly reactive molecule. Each year 12.4 million metric tons are manufactured by the Haber process (N2 + 3H2 2NH3 at 400°C and 250 atm), principally for nitric acid production, which is then used to make fertilizers and explosives. As a fertilizer, ammonia can be utilized in three ways first by direct injection... 

The Haber process for ammonia manufacture, which operates above the critical point of ammonia. 

Bosch also helped develop Haber s process into an industrial process. In 1913, Haber and Bosch opened an ammonia manufacturing plant in Germany. A year later, World War I started. Saltpeter had another use besides making fertilizer. It was also necessary to make nitric acid that was used to make explosives. When the war started, the British Navy quickly cut off Germany s supply of Chilean saltpeter. If not for the Haber process, some historians estimate that Germany would have run out of nitrates to make explosives by 1916. The war lasted another two years, however, because Germany did not need to rely on outside sources of nitrates for fertilizers or explosives. 

Example The Haber process used to manufacture ammonia N2(g) + 3H2(g) = 2NH3(g) AH = -46kJmor ... 

The conditions used industrially for the Haber process are those that sustain the economic viability of its manufacture. Out of necessity, a high yield in a long time must be balanced against a low yield in a shorter time, whilst minimising energy costs. The conditions employed indicate a compromise between these opposing outcomes, as the graphs illustrate. 

What happens to a system at equilibrium if the concentration of one of the reacting chemicals is changed This question has practical importance, because many manufacturing processes are continual. Products are removed and more reactants are added without stopping the process. For example, consider the Haber process that was mentioned in the previous Sample Problem. 

In this chapter, you learned about the Haber process for manufacturing ammonia. You used this process to help you understand various concepts related to equilibrium. As you can see in Figure 7.11, ammonia is a valuable industrial chemical. Its annual global production is well over 100 million tonnes. The vast majority of ammonia, roughly 80%, is used to make fertilizers. You will now examine how the equilibrium concepts you have been studying work together to provide society with a reliable, cost-effective supply of ammonia. 

The most important uses of synthesis gas are the manufacture of ammonia (NH3) via the Haber process. A mixture of nitrogen and hydrogen are passed over an iron catalyst (with aluminum oxide present as a "promoter"). The operating conditions are extreme—800°F and 4000 psi,... 

The importance of catalysts in chemical reactions cannot be overestimated. In the destruction of ozone previously mentioned, chlorine serves as a catalyst. Because of its detrimental effect to the environment, CFCs and other chlorine compounds have been banned internationally. Nearly every industrial chemical process is associated with numerous catalysts. These catalysts make the reactions commercially feasible, and chemists are continually searching for new catalysts. Some examples of important catalysts include iron, potassium oxide, and aluminum oxide in the Haber process to manufacture ammonia platinum and rhodium in the Ostwald synthesis of nitric... 

Haber process The manufacture of ammonia from nitrogen and hydrogen, carried out at high pressure and high temperature with the aid of a catalyst. 

N2 + 3 H2 > 2 NH3 Fe, K20, and A1203 Haber process for synthesis of ammonia NH3 Manufacture of fertilizers, nitric acid... 

Approximately 95% of the H2 produced in industry is synthesized and consumed in industrial plants that manufacture other chemicals. The largest single consumer of hydrogen is the Haber process for synthesizing ammonia (Sections 13.6-13.10) ... 

Nitrogen In the production of ammonia by the Haber process (see p. 176) the ammonia is then used to make nitric acid, which is used in the manufacture of dyes, explosives and fertilisers In liquid form, as a refrigerant As an inert atmosphere for some processes and chemical reactions, because of its unreactive nature for example, empty oil tankers are filled with nitrogen to prevent fires In food packaging to keep the food fresh, for example in crisp packets where it also prevents the crisps being crushed (Figure 11.10)... 

What conditions would you suggest for the manufacture of ammonia by the Haber process ... 

FIGURE 1 Ammonia manufacture from hydrogen and nitrogen by the Haber process. 

O chemical plant the reaction vessels and equipment for manufacturing chemicals O feedstock starting materials for chemical industrial processes O brine a concentrated solution of sodium chloride O Haber process the industrial process for the manufacture of ammonia O Contact process the industrial process for the manufacture of sulfuric aod... 

The demand for nitrogen in a chemically fixed form (as opposed to elemental nitrogen gas) drives a huge international industry that encompasses the production of seven key chemical nitrogen products ammonia, urea, nitric acid, ammonium nitrate, nitrogen solutions, ammonium sulfate and ammonium phosphates. Such nitrogen products had a total worldwide annual commercial value of about US 50 billion in 1996. The cornerstone of this industry is ammonia. Virtually all ammonia is produced in anhydrous form via the Haber process (as described in Chapter 2). Anhydrous ammonia is the basic raw material in a host of applications and in the manufacture of fertilizers, livestock feeds, commercial and military explosives, polymer intermediates, and miscellaneous chemicals35. 

The balanced equation that we will use for this stoichiometry explanation is the recipe for the manufacture of ammonia (NH3). This reaction was so important that the chemist responsible for it, Fritz Haber, was awarded the Nobel Prize. Ammonia is a gateway step in the manufacture of fertilizers, and its manufacture was a giant step in solving the problem of providing food to a world population growing at an exponential rate. The equation for the Haber process is... 

Obviously, the kinetics and the thermodynamics of this reaction are in opposition. A compromise must be reached, involving high pressure to force the equilibrium to the right and high temperature to produce a reasonable rate. The Haber process for manufacturing ammonia represents such a compromise (see Fig. 19.6). The process is carried out at a pressure of about 250 atm and a temperature of approximately 400°C. Even higher temperatures would be required if a catalyst consisting of a solid iron oxide mixed with small amounts of potassium oxide and aluminum oxide were not used to facilitate the reaction. 

A schematic diagram of the Haber process for the manufacture of ammonia. 

Much of the ammonia made by the Haber Process is used directly in the manufacture of fertilisers, but large quantities are also converted to nitric acid which is used in the ... 

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