Haber-Bosch process, ammonia

Sulfuric acid. (contact process) Ammonia (Haber-Bosch process)... 

The synthetic ammonia industry of the latter part of the twentieth century employs only the Haber-Bosch process (12—15), developed in Germany just before World War 1. Development of this process was aided by the concurrent development of a simple catalyzed process for the oxidation of ammonia to nitrate, needed at that time for the explosives industry. N2 and H2 are combined direcdy and equiUbrium is reached under appropriate operating conditions. The resultant gas stream contains ca 20% ammonia. 

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 ... 

The catalytic synthesis of ammonia from its elements via the Haber-Bosch process is of major industrial importance. The high pressure synthesis is catalyzed by Fe promoted with K20, CaO and A1203. 

Haber process (Haber-Bosch process) The catalyzed synthesis of ammonia at high pressure, half-cell One compartment of an electrochemical cell consisting of an electrode and an electrolyte, half-life (f1/2) (1) In chemical kinetics, the time needed for... 

The enzyme systems responsible for fixing atmospheric N2 to form ammonia are known as the nitrogenases. These enzymes function at field temperatures and 0.8 atm N2 pressure, whereas the industrial Haber-Bosch process requires high temperatures (300-400°C) and high pressures (200-300 atm) in a capital-intensive process that relies on burning fossil fuel. Small wonder, then, that the chemistry of the nitrogenases has attracted considerable attention for many years. 

Ammonia, another well known cleaner, is also used to manufacture fertilizers, nitric acid, sodium carbonate (washing soda), explosives, nylon, and baking soda. Ammonia is produced by combining nitrogen gas (obtained from the air) and hydrogen gas (obtained from natural gas) in a process called the Haber-Bosch process ... 

Five years after Haber patented his process, BASF opened its nitrogenfixing ammonia factory in 1913. The Haber-Bosch process, as it is now... 

Frank-Caro Also called the Cyanamide process. An early process for fixing atmospheric nitrogen. Lime and carbon were heated to produce calcium carbide this was reacted with nitrogen to give calcium cyanamide, which was hydrolyzed with steam to yield ammonia and calcium carbonate. Developed by A. Frank and N. Caro from 1895 at Dynamit, Germany, and used in Germany, Norway, and Italy until it was replaced by the Haber-Bosch process after World War I. 

Mont Cenis [Named after a coal mine in the Ruhr] An early ammonia synthesis process, basically similar to the Haber-Bosch process but using coke-oven gas. Operated by The Royal Dutch Group at Ymuiden, The Netherlands, since 1929. 

Industrially, ammonia has been produced from dinitrogen and dihydrogen by the Haber-Bosch process, which operates at very high temperatures and pressures, and utilizes a promoted iron catalyst. Millions of tons of ammonia are generated annually for incorporation into agricultural fertilizers and other important commercial products. The overall reaction is exergonic, as indicated in equation 6.1 ... 

Due to the high hydrogen storage capacity of the ammonia molecule (17.7 wt% equal to an energy density of 4,318 Wh kg 1), its decomposition is intensely investigated for COx-free hydrogen production for mobile fuel cell applications [146]. However, compared with the well-established Haber Bosch process for ammonia synthesis, its decomposition is underdeveloped and requires substantial improvements before it can be considered as a practical contribution to the energy supply toolbox. 

Production of ammonia (NH ) Anhydrous (dry) ammonia is the fifth most produced industrial compound. The Haber-Bosch process uses steam on hot coke, which is mostly used in South Africa. In the United States, it is mostly produced from partial combustion of natural gas (methane) or by combining several gases using steam. Other methods use coke-oven gas, refinery gas (mostly methane), or even solar energy. Ammonia is toxic if inhaled and has a high pH value when mixed with water (hydration) to form ammonium hydroxide (NH OH), which has many uses, including as a household cleaner. Ammonia forms many compounds, including ammonium nitrate in fertilizer, rocket fuel, and explosives. Ammonia is also explosive when mixed with mercury or silver or when mixed as part of nitrocellulose. 

Iron has a rich surface coordination chemistry that forms the basis of its important catalytic properties. There are many catalytic applications in which metallic iron or its oxides play a vital part, and the best known are associated with the synthesis of ammonia from hydrogen and nitrogen at high pressure (Haber-Bosch Process), and in hydrocarbon synthesis from CO/C02/hydrogen mixtures (Fischer-Tropsch synthesis). The surface species present in the former includes hydrides and nitrides as well as NH, NH2, and coordinated NH3 itself. Many intermediates have been proposed for hydrogenation of carbon oxides during Fischer-Tropsch synthesis that include growing hydrocarbon chains. 

Ammonia is produced from nitrogen and hydrogen at elevated temperature (500 to 550°C) and pressure (200-350 atm) (Haber-Bosch process), using a promoted iron catalyst... 

It also is obtained as a by-product in the Haber-Bosch process for the manufacture of ammonia. The method involves passing steam and air over hot coke. 

Reduction in price of raw material (nitric acid) by the commercialization of the Haber-Bosch process for ammonia synthesis. 

Haber process (Haber-Bosch process) The catalyzed synthesis of ammonia at high pressure and high temperature. 

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