What is Ammonia?
Ammonia is a molecule consisting of nitrogen and hydrogen covalently attached with an angular bond at about 1070 (Figure 1.1).The colourless gas, with a molecular formula of NH3 (Equation 1), is a significantly contributor to nutritional and pharmaceutical needs of people around the globe. However, on estimate, 83% of the ammonia produced is used in fertilisers. The Haber process, is the main industrial procedure for the production of ammonia .The process converts atmospheric nitrogen (N2) to ammonia (NH3) by a reaction with hydrogen (H2) using a metal catalyst under high temperatures and pressures. When examining equation 1, it is most evident that this process is an equilibrium reaction, meaning the reaction can shift to either side of the reaction depending of factors such as pressure, temperature and availability of reactants

Ammonia Production
The ingredients into making the final product of ammonia are natural gas, air and water. In the first stage, natural gas (which is mostly methane) is reacted with steam to produce carbon dioxide and hydrogen. To speed up the reaction, a nickel (Ni) catalyst is used. A high temperature and a high pressure also speeds up the reaction.

CH4(g) + H2O(g)
Ni catalyst
---------->
700oC
CO(g) + 3H2(g)

In the second stage, some of the methane from the first stage is burnt in air. The oxygen in the air reacts with the hydrogen to make steam. The reason for this second stage is to remove the oxygen from the air to leave nitrogen behind. With the heat that this process creates is used then used to run the Haber process.
2CH4(g) +
O2(g) + 4N2(g)
(air)
Ni catalyst
--------->
2CO(g) + 4H2(g) + 4N2(g)

In the third stage, the Haber-bosch process occurs. Having obtained the hydrogen and nitrogen gases (from natural gas and the air respectively), they are pumped into the compressor through pipes. These gases are reacted at a 3:1 ratio and then pressurised to about 200 atmospheres inside the compressor. Following this, the pressurised gases are pumped into a tank containing beds of iron catalyst (to speed up the reaction) at about 450°C. In these conditions, some of the hydrogen and nitrogen will react to form ammonia. The unreacted nitrogen and hydrogen, together with the ammonia, pass into a cooling tank. The cooling tank functions to liquefy the ammonia, which can be removed into pressurised storage vessels. The unreacted hydrogen and nitrogen gases removed from the cooling tank are then finally recycled by being fed back through pipes to pass through the hot iron catalyst beds again. The diagram shows a simplified version of the ammonia production process (figure 1.2).

The Haber Process for Making Ammonia (Figure 1.2)

Le Chatelier’s Principle In Ammonia Production
As per equation 1 the forwards reaction is favoured, so more ammonia (product) will be produced. Therefore, the equilibrium needs to be seated to the right side of the equation, and it is attempted to shift the process maximum to the right. This is possible by stressing the system accordingly and for that Le Chatelier’s Principle has to be applied.
The production reaction is exothermic (ΔH = −92.4 kJ/mol) which means that reducing the temperature will cause the forward reaction to be more favoured (as it is trying to regenerate heat).
However, because it is not very exothermic the reaction is slow at room temperature. The obvious way to make it faster is to raise the temperature, but that would be bad as it would favour the reverse process and consume ammonia instead of producing it.

For that matter pressure can also be increased. However, there are safety issues with working at high pressures. Still, if pressure were increased, it would favour the forwards reaction and produce ammonia as there are four reactant moles to just two product moles

Furthermore, an iron-based catalyst is used to increase the rate of the reaction at room temperature without affecting the position of