Fertiliser ammonia

Markets. Industrial use of ammonia varies according to region. Eor example, industrial usage represents 20% of the ammonia production in the United States and Western Europe, 10% in the USSR, 1—10% in Asia, and 5% in Latin America and North Africa (79). Fertiliser ammonia consumed domestically in most countries is converted to straight or compound fertilisers such as urea, ammonium nitrate, diammonium phosphate, and various grades of mixed fertilisers. However, almost 29% of ammonia nitrogen in the United States is consumed as direct appHcation material. The use of nitrogen solution such as urea and ammonium nitrate (UAN) has also become popular in the United States and the USSR. 

Uses of ammonia and ammonium compounds. Most of the ammonia produced is used in the manufaeture of nitrogenous fertilisers such as ammonium sulphate. Other uses include nitric acid and synthetic fibre and plastic manufacture. 

At atmospheric pressure and at its melting point, urea decomposes to ammonia, biuret (1), cyanuric acid (qv) (2), ammelide (3), and triuret (4). Biuret is the main and least desirable by-product present in commercial urea. An excessive amount (>wt%) of biuret in fertiliser-grade urea is detrimental to plant growth. 

Transportation and Distribution Cost. Although much ammonia serves as feedstock for other processes, the largest single use in the United States is as a direct appHcation fertiliser without further processing. This direct appHcation consumption is mosdy in the farm belt and ammonia produced in the Gulf Coast states is shipped to terminal faciUties and then distributed by retail outlets to the farmer. 

Because of the nature of the industry, agricultural ammonia consumption is cycHc. During the Spring fertiliser season, about 75% of the dedicated production is sold. 

There are a considerable number of stable crystalline salts of the ammonium ion [14798-03-9] NH. Several are of commercial importance because of large scale consumption in fertiliser and industrial markets. The ammonium ion is about the same size as the potassium and mbidium ions, so these salts are often isomorphous and have similar solubiUty in water. Compounds in which the ammonium ion is combined with a large, uninegative anion are usually the most stable. Ammonium salts containing a small, highly charged anion generally dissociate easily into ammonia (qv) and the free acid (1). At about 300°C most simple ammonium salts volatilize with dissociation, for example... 

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. 

Isobutyraldehyde reacts with aqueous ammonia at 0—10°C to give hexahydro-2,4,6-ttiisopropyl-r-ttiazine, (4) (18), whereas under refluxing conditions the enea2omethine [5339-41-3] (5), is formed (19). Isobutyraldehyde condenses with two mole equivalents of urea in the presence of an acid catalyst to give isobutyUdenediurea [2224-20-6] (IBDU), (6) a slow release fertiliser (20). 

Calcium cyanamide (lime nitrogen) has been used as a fertiliser (6). It hydrolyses ia moist soil to produce ammonia ... 

Nitrogen compounds These also arise from both natural and synthetic sources. Thus ammonia is formed in the atmosphere during electrical storms, but increases in the ammonium ion concentration in rainfall over Europe in recent years are attributed to increased use of artiflcial fertilisers. Ammonium compounds in solution may increase the wettability of a metaland the action of ammonia and its compounds in causing season cracking , a type of stress-corrosion cracking of cold-worked brass, is well documented. 

Because nitrogenous fertilisers promote plant growth, ammonia solution (which is alkaline) is neutralised by dilute nitric acid to form ammonium nitrate. 

Fillery IRP, Simpson JR, De Datta SK. 1986. Contribution of ammonia volatilization to total nitrogen loss after applications of urea to wetland rice fields. Fertiliser Research 8 193-202. 

For birds, insects, and reptiles, which have an egg stage during development, so that water availability is severely restricted, the synthesis of a highly soluble excretory product would have serious osmotic consequences therefore most of the ammonia is converted to the virtually insoluble uric acid (urate). This product can be safely retained in the egg or excreted as a slurry of fine crystals by the adult. In birds that nest colonially this can accumulate in massive amounts on islands off the coast of Peru cormorants have deposited so much that this guano (hence the name guanine) is collected for use as a fertiliser. Uric acid is less effective as an excretory product, since it has a lower nitrogen content than urea (33%) and is more expensive to synthesise (2.25 molecules ATP per atom of nitrogen). Mammals do produce uric acid but as a product of purine catabolism (see above). 

Although NH3 is not one of the greenhouse gases, NHs-emissions cause negative environmental effects through soil acidification and uncontrolled nitrogen re-circulation. The latter is due to ammonia losses from organic and mineral fertilisers and re-import from the atmosphere to soil by precipitation. 

Manganese dioxide can be used to absorb the initially low concentration SO2 to produce the sulphate in a Mitsubishi Process (23). In this case the absorbing phase is itself the oxidising agent. Regeneration with ammonia and air simultaneously produces ammonium sulphate which can be directly marketed as a fertiliser, thus the calcium ion problem of the dry limestone process is replaced by a plant nutrient ion -... 

Nitrous oxide contributes severely to global warming and the depletion of ozone in the stratosphere (Crutzen 1981, Bouwman 1996). Almost 90% of the global atmospheric N2O is formed during the microbial transformation of nitrate (NO ) and ammonia (NH ) in soils and water. In OECD countries the agricultural contribution to N2O emissions is estimated at 58% (IPCC 2001). Soils fertilised with inorganic fertilisers and manure stores are seen as the largest sources (Chadwick et al. 1999, Brown ef al. 2002). 

The element has a definite fertilising action 2 which is exerted in two ways (1) It supplies sulphuric acid by bacterial oxidation, the presence of the acid increasing the availability of certain mineral constituents in the soil, such as alkalis, ferric oxide, alumina and phosphates. (2) It facilitates the work of the ammonia and nitrifying bacteria, thus placing larger supplies of nitrogen at the disposal of the plants. But although such action may be beneficial in some soils it is equally harmful in others, and sulphur should not be applied to a soil already acid.3... 

To determine the alkalies, another 200 c.c. of the liquid are evaporated to dryness, the residue being gently calcined and taken up in water and hydrochloric acid, and the non-alkali metals eliminated by means of ammonia and ammonium carbonate.1 The filtrate is evaporated to dryness with a little sulphuric acid and the residue heated to expel the ammonium salts and then weighed this gives the sodium and potassium sulphates together. If required, the two metals may be determined separately (see Fertilisers, Vol. I, pp. 124 and 135). 

Oudendag DA, Luesink HH (1998) The Manure Model manure, minerals (N, P and K), ammonia emission, heavy metals and the use of fertiliser in Dutch agriculture. Environ Pollut 102 241-246... 

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