Nitrogenous fertilizer, synthetic

Nearly all commercial nitrogen fertilizer is derived from synthetic ammonia. However, prior to the introduction of ammonia synthesis processes in the early 1900s dependence was entirely on other sources. These sources are stdl utilized, but their relative importance has diminished. 

Over 95% of all commercial nitrogen fertilizer in the 1990s is derived from synthetic ammonia (qv). Worldwide, the yearly production of synthetic ammonia is about 120 million t, of which about 85% finds use in fertilizers. 

Petrochemicals in general are compounds and polymers derived directly or indirectly from petroleum and used in the chemical market. Among the major petrochemical products are plastics, synthetic fibers, synthetic ruhher, detergents, and nitrogen fertilizers. Many other important chemical industries such as paints, adhesives, aerosols, insecticides, and pharmaceuticals may involve one or more petrochemical products within their manufacturing steps. 

Water pollution trends have particularly worsened in China in recent years. The industrial development (as certified from oil demand) and the intensive agriculture (China is the world s largest consumer of synthetic nitrogen fertilizers) pose a threat to water bodies. 

The effect that nitrogen-containing synthetic fertilizers can have on yields is illustrated in Figure 15.13. It requires a lot of energy to mine and refine synthetic fertilizers, however, and so they are expensive. For example, of the total energy required to produce corn in the United States, at least one-third is needed to produce, transport, and apply the fertilizer. Nevertheless, synthetic fertilizers are widely used, and our present food supply depends on them. 

What process is used to generate most synthetic nitrogen fertilizer ... 

Chemical fertilizers Synthetically produced mineral forms of nitrogen, phosphorous, and potassium given to plants to enhance growth. Require large amounts of fossil fuels for synthesis. 

On a worldwide basis, nitrogen fertilizer consumption accounts for more than 85 percent of the total nitrogen industry. In the United States, with its significant industrial markets, fertilizer use accounts for only approximately 80 percent of total nitrogen consumption.35 About 97 percent of nitrogen fertilizers are derived from synthetically produced ammonia. The rest are produced as... 

The food supply could be increased due to the use of different hybrid varieties, improved techniques of farming, better seeds, insecticides and herbicides for the eradication of parasites and weeds, but mostly due to the intensive use of natural and synthetic fertilizers. Therefore, the dependence on chemical fertilizers, especially those containing nitrogen, is a hallmark of high-intensity agriculture and since 1960 the worldwide rate of application of nitrogen fertilizers has been increasing (Tilman, 1998). 

Ammonium sulfate is a coproduct in the production of synthetic-fiber intermediates, such as caprolactam, acrylonitrile, and methyl methacrylate, and in the production of formic acid and acrylamide. The recovery of ammonium sulfate form these syntheses has gained importance in the last thirty years. Almost all of the 2.8 megatons of ammonium sulfate produced annually is used as fertilizer. In industrial countries, ammonium sulfate is almost always a coproduct or by-product in other processes and can only be sold as fertilizer, mostly in developing countries. In Ihese couniries, its low nitrogen content makes the transportation cost per unit of nitrogen higher than for other nitrogen fertilizers. 

Sodium nitrate is used as a fertilizer and in a number of industrial processes. In the period from 1880—1910 it accounted for 60% of the world fertilizer nitrogen production. In the 1990s sodium nitrate accounts for 0.1% of the world fertilizer nitrogen production, and is used for some specific crops and soil conditions. This decline has resulted from an enormous growth in fertilizer manufacture and an increased use of less expensive nitrogen fertilizers (qv) produced from synthetic ammonia (4 )5 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. 

Ammonia is an essential building block for synthetic nitrogen fertilizers and finds widespread use in the production of synthetic fibers, explosives, and plastics. 

Crop rotation is already widely practiced to use these natural ways to maintain nitrogen fertility. Genetic engineering experiments may increase the number of species of plants that are able to do this, and in this way decrease the agricultural demand for synthetic fertilizer nitrogen [71]. 

Fertilizers (synthetic nitrogenous and others) Formaldehyde (solid and solution)... 

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