Synthetic Ammonia Manufacture

Operational Constraints and Problems. Synthetic ammonia manufacture is a mature technology and all fundamental technical problems have been solved. However, extensive know-how in the constmction and operation of the faciUties is required. Although apparendy simple in concept, these facihties are complex in practice. Some of the myriad operational parameters, such as feedstock source or quaUty, change frequendy and the plant operator has to adjust accordingly. Most modem facihties rely on computers to monitor and optimize performance on a continual basis. This situation can produce problems where industrial expertise is lacking. 

Z. TECHNICAL MANUFACTDBE OF AMINO COMPOXINDS Synthetic Ammonia Manufacture... 

Manufacture. The history of ammonium chloride manufacture is linked to the birth of the soda and synthetic ammonia iadustries. Consequendy this haUde has always been a by-product ia great supply. Production by direct reaction of ammonia and hydrochloric acid is simple but usually economically unattractive a process based on metathesis or double decomposition is generally preferred. 

Sodium nitrate is used as a fertiliser and in a number of industrial processes. In the period from 1880—1910 it accounted for 60% of the world fertiliser nitrogen production. In the 1990s sodium nitrate accounts for 0.1% of the world fertiliser nitrogen production, and is used for some specific crops and soil conditions. This decline has resulted from an enormous growth in fertiliser manufacture and an increased use of less expensive nitrogen fertilisers (qv) produced from synthetic ammonia (qv), such as urea (qv), ammonium nitrate, ammonium phosphates, ammonium sulfate, and ammonia itself (see Ammonium compounds). The commercial production of synthetic ammonia began in 1921, soon after the end of World War I. The main industrial market for sodium nitrate was at first the manufacture of nitric acid (qv) and explosives (see Explosives and propellants). As of the mid-1990s sodium nitrate was used in the production of some explosives and in a number of industrial areas. 

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 ... 

Ammonium nitrate is the most readily available and cheapest salt of nitric acid, now manufactured wholly from synthetic ammonia and from nitric acid obtained by oxidation of ammonia. Ammonium nitrate was prepared for the first time as early as in 1659 by Glauber. The original experiments with it as a component of explosive mixtures began in the second half of the nineteenth century. Ammonium nitrate is the most widely used oxygen carrier, since it is an ingredient of the commonest group of high explosives. The reasons for this are to be seen in its properties and those of its explosive mixtures appreciable chemical stability, and low sensitiveness to friction and to shock. 

Ammonium sulfate was originally manufactured by using sulfuric acid to scrub by-product ammonia from coke-oven gas, and much is still produced in this manner. Most of the ammonium sulfate produced is now made by reaction between synthetic ammonia and sulfuric acid. 

Ammonia is the second largest synthetic commodity manufactured by the chemical industry, with the global production capacity exceeding 140 million metric tons. Haber, in 1909, demonstrated that ammonia can be produced at a high pressure by the reaction... 

Large scale manufacture of synthetic ammonia is exclusively carried out with synthesis gas (Nj -i- 3H2 this... 

Manufacture.—It may be produced by leading vapours of ammonia into nitric acid, using synthetic ammonia and Ostwald s rritric acid (see p. 29). 

Manufacture of Nitric Acid from Synthetic Ammonia... 

It will be seen from the above equation that large amounts of energy are mot required for the production of ammonia from its elements, and that, therefore, the manufacture of synthetic ammonia need not be confined to districts where large amounts of cheap water-power are available, as is the case with the electrical production of nitric acid, cyanamide, etc. 

It has been stated that the total costs of manufacturing ammonium sulphate from this synthetic ammonia only amounts to 2. 6s. 6d. per ton, and so the process appears to be the one which lias a greater chance of success as regards low cost than any other method yet proposed, especially as the plant can be erected anywhere (see p. 28). 

According to J. Louis 1 oucar, since cyanamide has to be made from calcium carbide and nitrogen, and the calcium carbide in its turn from lime and a plentiful supply of electrical energy, the ammonia made by this process could not, theoretically, be prodneed as cheaply ns the direct synthetic ammonia prepared by direct union of nitrogen and hydrogen. Foucar (private communication) worked out the costs of manufacture of ammonium sulphate from cyanamide as follows —... 

A great many patents describe preparation, use, and regeneration of the fluidized catalyst. Fused iron of the synthetic ammonia type is mentioned for catalyst manufacture and such ores as hematite, limonite, magnetite, pyrite, as well as mill scale, bloom scale, and other materials. 

The salt, gypsum, sodium sulfate, soda ash, carbonates, borax, natural nitrate, and many other industries that take their raw materials from saline residues are all, by necessity, located directly at the source of supply. The location in West Virginia of a company for the manufacture of synthetic ammonia was for the purpose of being near the coal fields that supply the necessary raw materials. 

For developments in ammonia synthesis during the late 1920s, and in particular of compressors see High pressures in the manufacture of synthetic ammonia. Recent designs in compressing plant, Chemistry and Industry, 48 (1929), 591-598. 

BASF owns processes for the production of synthetic ammonia, which are used in its works at Oppau and Merseburg. BASF has taken out various patents in France to protect these processes. The French government, which desires to use and carry out these patents and processes in France, has regarded it as expedient, to this end, to secure the voluntary cooperation of BASF in connection with the utilization both of said patents and processes and of the keys to the industrial secrets which are necessary or useful for the purposes of manufacture and operation, and the use of more recent improvements or those which are still at the development stage. 

The high rate of growth of the synthetic ammonia industry and the corresponding manufacturing departments of LG. Farben in Oppau and Leuna. These departments called for new chemists to join the production facilities via the Ammonia Laboratory ... 

It is self evident that novel products must satisfy human needs if they are to become the basis of commercial manufacturing processes. The range of organic products changed as a result of World War I, particularly with the increased use of electrical equipment and motorized transport. Further, the absence of previously abundant raw materials, as well as the fear of shortages, stimulated research and development in both Allied and German academic and industrial laboratories. Work on the production of nitric acid from synthetic ammonia, and on synthetic petroleum and synthetic rubber, underscored the new needs, particularly the growing reliance on new industries. It mattered little that the basic chemistry was not understood. It was more important that the new products could be easily processed by users. 

Fatty adds are predominantly used as intermediates. Main applieations are water soluble soaps for household eleaning, personal care, industrial and institutional (I I) cleaning and synthetic rubber manufacturing by emulsion polymerization. Soaps are made by reaction of fatty acids with caustic alkalis, alkali carbonate or ammonia or (>90%) by direct saponification of the triglyceride oil. Another important group of fatty add soaps are dry, water-insoluble metal soaps used as lubricants or stabilizers for PVC and other plastics and aqueous calcium stearate dispersions applied as paper coating... 

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