Question

In the manufacture of ammonia by Haber’s process. Write the flow chart and chemical equations with optimum conditions.

Answer 1

Ammonia is manufactured by the direct combination of nitrogen and hydrogen in the ratio 1:3 by volume. 

Reaction: N₂ + 3H₂(g) ⇌ 2NH₃(g); 

ΔH = -46 kJ/mol 

According to Le-Chatelier’s principle, high yield of Ammonia is obtained under the following favourable conditions. 

(a) High pressure of 200atm 

(b) Temperature of ~ 700K 

(c) Use of Iron oxide as Catalyst in presence of small amounts of K₂O and Al₂O₃ as promoters.

Procedure; 

Step-1: Dry N₂ and H₂ in the ratio 1:3 compressed at 200 atm in compresser. 

Step-2: Compressed gas passed through catalytical chamber, in presence of Fe, catalytical promoter Mo and 700 K forms ammonia. 

Step-3: The ammonia formed is cooled in coolent below 239 K. 

Step-4: The unreacted nitrogen and hydrogen are recirculated to compressor using pump. The above step repeated to get maximum yield.