The chemical, ammonia, has broad application in both industry and agriculture. During the last century, considerable quantities of this compound have been produced. Although ammonia itself is not inherently poisonous, severe exposures may cause airway destruction and burns of the skin. Moreover, under certain conditions, ammonia can burn or explode. Given the chemical's widespread occurrence, the management of ammonia merits careful analysis.
It remains a relatively unknown fact that the first synthesis of ammonia ranks as one of the most important discoveries in the history of science. In 1840, Justus von Leibeg concluded that a significant component of plant nutrition was "fixed" nitrogen. At that time, fixed nitrogen was available in the form of ammonium sulfate and sodium nitrate. However, towards the end of the 1800s, there was concern that the world's natural nitrate supplies would become exhausted. Mankind was faced with the possibility of devastating food shortages.
Fortunately though, in 1913, scientists produced the first synthetic ammonia. The Haber-Bosch process synthesizes ammonia directly from its inherent elements. Fritz Haber began working on the thermodynamic equilibria between ammonia, hydrogen, and nitrogen around 1904. Both he and Carl Bosch eventually discovered that "by repeating the process of hydrogenation of the nitride and its formation under steady-state conditions, ammonia may be formed catalytically over a metal." The reaction for this process occurs as follows: N2(g) + 3H2(g) ? 2NH3(g). The metal, iron, may be used as a catalyst. In most ammonia plants, the nitrogen is derived from air and the hydrogen comes from natural gas. These plants generally have an average capacity of 1,000 or more tons of ammonia per day.
Ammonia gas is colorless and sharply pungent. In addition, at ambient temperatures, the gas is lighter than air. Under hyperbaric conditions, ammonia may ...