1. AMMONIA
Prepared by – Mr. Vishal B. Thakare
(M.Tech, Chemical, SVNIT Surat)
Assistant Professor, PARUL UNIVERSITY
Vadodara
vishalbt88@gmail.com
2. AMMONIA
Ammonia (NH3) is a compound of nitrogen and hydrogen. It is a
colorless gas with a characteristic pungent smell.
It is one of the most important nitrogenous material. It is a base from
which all the nitrogen containing compounds are derived.
Raw materials
1000kg of NH3 (85% yield)
Hydrogen = 210kg
Nitrogen = 960kg
Catalyst = 0.2kg
Power = 850KWH
Reaction
N2(g) + 3H2(g) 2NH3(g) ΔH = - 22.0kcals
3.
4. Most widely used catalyst for ammonia synthesis is iron with added
promoters e.g. oxides of aluminium, zirconium or silicon at about 3%
concentration and potassium oxide at about 1%. These prevent sintering
and make the catalyst more porous.
The liquid nitrogen wash has the function to remove residual impurities
like CO, Ar and CH4 from a crude hydrogen stream and to establish a
stoichiometric ratio H2/N2 = 3:1.
The manufacture of ammonia is carried out by passing mixture of pure
hydrogen and nitrogen in the proportion of 3:1 by volume under pressure
(100-1000atm depending on conversion required).
Gas flows next through the inside of the tube which contains promoted
iron catalyst at 500-550oC
5. The NH3 is removed by condensation, first with water cooling and
then NH3 refrigeration.
Liquid ammonia is passed into separator section where unreacted
ammonia and hydrogen is separated and liquid ammonia get
collected in storage tank.
Unreacted ammonia and hydrogen get reacted in ammonia converter
which contains promoted iron catalyst at 500-550oC.
Same way after the reaction mixture cooled by water and NH3
refrigeration. Condensate ammonia get separated in separator
section.
