Ammonia is a widely used product.

In 1716, J. Kunckel mentioned the formation of Ammonia during fermentation. S. Hales, in 1727, observed that heating lime (Calcium Oxide – CaO) with Ammonium Chloride in a retort that allowed the gas to be collected over water did not seem to release any gas; on the contrary, all the water was drawn into the retort. However, it was Joseph Priestley, in 1774, who 'discovered' Ammonia. He repeated Hales' experiment, but in a pneumatic chamber with mercury, and obtained what he called 'alkaline air,' which was nothing more than gaseous Ammonia with the formula NH3.

Claude-Louis Berthollet, in 1784, decomposed the gas using an electric spark, establishing its composition as 3 (three) volumes of hydrogen and 1 (one) volume of nitrogen. This was the first elemental analysis of ammonia, which led to the understanding of its formula.

The first industrial-scale production occurred in 1913, in Germany, using the Haber-Bosch process. The ammonia production process essentially involves the reaction between nitrogen and hydrogen under high pressure and temperature, in the presence of a catalyst, as indicated by the following equation:

N2 + 3H2 = 2NH3

Before the advent of the synthetic ammonia industry, the main source of this nitrogen compound was the gases produced from coal coking operations.

The nitrogen used in ammonia synthesis is derived from the air. However, a wide variety of sources are used to obtain the nitrogen required for the process.

The Haber-Bosch process is the main method for obtaining ammonia, but there are currently many other processes. In laboratories, for example, ammonia is obtained by heating ammonium chloride with calcium hydroxide, with the formula Ca(OH)2, as shown in the reaction below:

2 NH4Cl + Ca(OH)2 = CaCl2 + 2NH3 + H2O

2.1 General Informations

Ammonia (NH3).

Chemical name of the substance composed of one nitrogen atom and three hydrogen atoms (NH3). Obtained from atmospheric nitrogen and process hydrogen at high temperature and pressure in the presence of a catalyst. Toxic and corrosive gas.

Used as a refrigerant gas, and as a basic component for the manufacture of fertilizers, nitric acid, and ammonium nitrate.

It exists in the liquid state at low temperatures or relatively high pressures. It is a colorless gas, but at high concentrations, it produces a visible vapor cloud with a strong alkaline reaction. It has a characteristic, pungent, and penetrating odor.

Used as a refrigerant gas, and as a basic component for the manufacture of fertilizers, nitric acid, and ammonium nitrate.

Corrosive to copper and galvanized surfaces.

It is highly soluble in water; at 0 ºC and 760 mm/Hg, one volume of water dissolves about 1,300 volumes of gas, and at 20 ºC, the same volume of water dissolves 710 volumes of the gas. When dissolved in water, it generates heat and forms ammonium hydroxide (NH4OH).

The expansion of Anhydrous Ammonia in air at 0°C is approximately 900 times, meaning 1 liter of liquid ammonia equates to 900 liters of ammonia gas.

2.2 Synonyms:

Ammonia

Ammonia Gas

Nitrogen Hydride

Anhydrous Ammonia

2.3 Technical Sheet

Risk number = 268

Class 2 – Compressed, liquefied, dissolved under pressure or highly refrigerated gas

Class 6 – Toxic substance

Class 8 – Corrosive

UN code number = 1005

Risk class or subclass = 2

Description of the risk Class or Subclass = Toxic Gas

CAS = 7664-41-7

Stability and Reactivity

3.1 Specific conditions

1. a) Stability: Anhydrous Ammonia is stable when stored and used under normal storage and handling conditions. Above 450°C, it can decompose, releasing nitrogen and hydrogen. Polymerization does not occur.
2. b) Hazardous Reactions: This product is an alkaline gas that emits heat when reacting with acids. In contact with halogens, boron, 1,2-dichloroethane, ethylene oxide, platinum, nitrogen trichloride, and strong oxidizers, it can cause potentially violent or explosive reactions. Contact with heavy metals like mercury leads to highly explosive reactions. Interaction with chlorine and its compounds can result in the release of chloramide gas. Anhydrous Ammonia forms a significant explosive mixture when in contact with hydrocarbons. The product is also incompatible with acetaldehyde, acrolein, hydrazine, and potassium ferrocyanide.

Conditions to Avoid: Avoid contact with high temperatures and fire, and do not provoke reactions with incompatible substances.

3.2 Hazardous decomposition products

Thermal decomposition of NH3 can produce toxic nitrous gases.

Molecular Weight: 17.03 g/mol

Specific density:  0.682 g/cm3

Vapor density:  0.597 g/cm3

Color:  Colorless gas

Boiling point: 33.35°C

Melting point: -77.7°C

Critical temperature:   132.4 °C

Critical pressure: 111.5 atm.

Vapor pressure:   10 atm. at 25.7°C

Heat of combustion: – 4440 cal/g

Viscosity:  0.255 cp at -33.5°C

Solubility in water: Miscible

Odor:  Ammoniacal, quite pungent

Explosive limit in air by volume %: 15 to 28%

Auto ignition temperature: 850°C or 651°C (in the presence of iron as catalyst)

Dissociation temperature:   above 400°C

Burning rate:  1 mm/min