Sulphur (S) is an important element in nature. As a constituent of proteins, has a similar nutrient value to nitrogen (N) and is essential to the life of plants, with its lack causing similar effects to the lack of nitrogen.

It is found in meteorites, volcanoes, hot springs, and as galena, gypsum, Epsom salts and barite. It is also a minor constituent of fats, body fluids, and skeletal minerals. Sulphur is a pale yellow, with a slight rotten egg odour, brittle solid, which is insoluble in water but soluble in carbon disulphide. As a native element in nature, it can be extracted using the Frasch process, which means that sulphur can be extracted from underground without mining it. In the Frasch process, underground deposits of sulphur are forced to the surface using superheated water and steam (to melt the sulphur) and compressed air. This gives molten sulphur, which is allowed to cool in large basins. Purity can reach 99.5%. The process is energy intense. However, sulphur is also produced chemically as a by product of crude oil and natural gas, in crush lump, flake and prilled form.

Urea is produced commercially from two raw materials, ammonia and carbon dioxide. Large quantities of carbon dioxide are produced during the manufacture of ammonia from coal or from hydrocarbons such as natural gas and petroleum derived raw materials. This allows direct synthesis of urea from these raw materials.

It has a number of advantages over other nitrogen fertilizers. It is safer to ship and handle, it is less corrosive to equipment, it has a higher analysis than any other dry nitrogen fertilizer and it can be used on virtually all crops. It can be stored and distributed through conventional systems. It can be applied in many different ways from sophisticated aerial application equipment to a farm spreading urea by hand. It is also highly water soluble so it moves readily into the soil. The high analysis means a reduced transportation and application cost per kilogram of nitrogen.

Urea serves an important role in the metabolism of nitrogen-containing compounds by animals and is the main nitrogen-containing substance in the urine of mammals. It is a colorless, odorless solid, highly soluble in water and practically non-toxic. Dissolved in water, it is neither acidic nor alkaline. The body uses it in many processes, the most notable one being nitrogen excretion. It is widely used in fertilizers(Chemicals & Fertilizers) as a convenient source of nitrogen. It is also an important raw material for the chemical industry.