Ammonium nitrate production commercial processes

Manufacture. Historically, ammonium nitrate was manufactured by a double decomposition method using sodium nitrate and either ammonium sulfate or ammonium chloride. Modem commercial processes, however, rely almost exclusively on the neutralization of nitric acid (qv), produced from ammonia through catalyzed oxidation, with ammonia. Manufacturers commonly use onsite ammonia although some ammonium nitrate is made from purchased ammonia. SoHd product used as fertilizer has been the predominant form produced. However, sale of ammonium nitrate as a component in urea—ammonium nitrate Hquid fertilizer has grown to where about half the ammonium nitrate produced is actually marketed as a solution. 

Conversion of nitric acid was not tested or evaluated in this study. However, the excess nitric acid was analyzed and found to be free of organics, agents. Schedule 2 compounds, and decomposition products. Therefore, conversion of nitric acid to ammonium nitrate, a commercially viable process, appears to be feasible. 

Three steps are essential to ammonium nitrate manufacture neutralization of nitric acid with ammonia to produce a concentrated solution evaporation to give a melt and processing by prilling or granulation to give the commercial soHd product. 

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. 

In the original process the cellulose nitrate itself was used as the fiber (hence its satirical description as mother-in-law silk ). The regenerating agent is ammonium hydrosulfide. The basic process was first demonstrated by J. W. Swan in London in 1885 but commercialized by Count L. M. H. B. de Chardonnet ( Father of the rayon industry ) in France in 1891 and operated there until 1934. The last working factory, that in Brazil, was burnt down in 1949. The other processes for making rayon fibers by regenerating cellulose ( viscose, cupram-monium) gave superior products. See also Rayon. 

Recent developments to the hydrothermal process include improvements in yield and reaction rate and in overcoming the difficulty associated with the coproduct salt. One method of overcoming the co-product problem is to use magnesium nitrate instead of chloride, with the ammonium nitrate being utiHsed for fertiliser production [102-104]. At least one plant based on this concept is now in commercial production. While a considerable advance on the initial chloride process, the nitrate route does require close integration with a fertiliser process and thus lacks flexibility. An alternative approach being developed is to recycle the ammonium salt co-product (nitrate or chloride) and use it to leach magnesium oxide, a potentially inexpensive raw material [103]. 

FLOW DIAGRAM FOR THE PRODUCTION OF AMMONIUM NITRATE BY THE STENGEL PROCESS (COMMERCIAL SOLVENTS)... 

An important point is that for most uses concerned with chemical production, the acid must be concentrated above its azeotropic point to greater than 95%(wt). Conversely, the commercial manufacture of ammonium nitrate uses nitric acid below its azeotropic point in the range 50-65%(wt). If the stronger chemical grade is to be produced, additional process equipment appropriate to super-azeotropic distillation is required. 

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. 

Summary TNTC is prepared by treating NIHT.HC1 with nitromethane and ammonium nitrate in the presence of trifluoroacetic anhydride. After the reaction, the TNTC is contaminated with a by-product and hence needs to be purified. To do this, the contaminated TNTC is treated with ethyl acetate, and reciystallized. Commercial Industrial note For related, or similar information, see Application No. 471,906, January 29, 1990, by Gencorp Aerojet, to Der-Shing Hunag, Folsom, CA. Part or parts of this laboratory process may be protected by international, and/or commercial/industrial processes. Before using this process to legally manufacture the mentioned explosive, with intent to sell, consult any protected commercial or industrial processes related to, similar to, or additional to, the process discussed in this procedure. This process may be used to legally prepare the mentioned explosive for laboratory, educational, or research purposes. 

Despite its brilliant results, it seems unlikely that the Solutia process can become a major source of phenol. Nitrous oxide availability is quite limited and its production on-purpose (by the conventional ammonium nitrate decomposition, which enables nitrous oxide of high purity to be produced for medical anesthetic applications, or even by selective oxidation of ammonia) would result too expensive. Therefore, the only reasonable scenario to exploit the Solutia process is its implementation close to adipic acid plants, where nitrous oxide is co-produced by the nitric oxidation of cyclohexanol-cyclohexanone mixtures and where it could be used to produce phenol instead of being disposed of However, the stoichiometry of the process is such that a relatively small phenol plant would require a world-scale adipic acid plant for its nitrous oxide supply. In fact, a pilot plant has been operated using this technology, but its commercialization has been postponed. 

Nitrous oxide is obtained in commercial quantities by the thermal decomposition of ammonium nitrate and by recovery from a by-product stream from adipic acid manufacturing processes. 

The aim of this chapter is to relate the detailed analysis of the ammonia synthesis reaction, as examined in other sections of this book, to the commercial operation of one of the major processes of the worldwide chemical industry. The present annual production of ammonia is in excess of 120 million tons per year and virtually all of this ammonia is produced from a mixture of hydrogen and nitrogen over a promoted iron catalyst operating at elevated temperature and pressure. Over 90% of ammonia produced is used as a fertilizer, principally in the form of urea or ammonium nitrate. 

Nuvalon A development of the Aloton process for extracting aluminum from clay. As in the Aloton process, clay is first heated with ammonium hydrogen sulfate. In the Nuvalon version, the product from this reaction is digested under pressure with 30% nitric acid, producing a solution of basic aluminum nitrate. Iron is removed by hydrolysis or by cooling. Normal aluminum nitrate is crystallized out and calcined to alumina. The process was piloted in Germany in 1951 but not commercialized. 

Ammonium carbonates.4—The normal carbonate, (NH4)2C03,H20, is produced by the action of ammonia on the solid commercial carbonate (p. 239) or its aqueous solution, and also by a similar process from ammonium carbamate.5 On account of its insolubility in concentrated ammonia solution, the salt crystallizes out. It can also be prepared by dry distillation of the commercial product, or by crystallization from a solution in dilute alcohol.5 It is also produced by heating barium or strontium carbonate with ammonium chloride or nitrate,6 and is stated to be formed by heating a mixture of nitric oxide and acetylene in presence of spongy platinum.7... 

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