Haber Process Haber's Process

Summary The Haber Process combines nitrogen from the air with hydrogen derived mainly from natural gas (methane) into ammonia. The reaction is reversible and the production of ammonia is exothermic

Summary German chemist Fritz Haber came up with this method of producing ammonia. Because early year in the century, Germany was having a war against the allies. The allies suddenly blocked the supply to Germany, so there was nothing to make ammonia to produce explosives. So Fritz Haber came up producing ammonia from air using iron catalyst.

A flow scheme of Haber's Process looks like this:

There are 1+3=4 molecules of gas on the left of the equation, only two molecules of gas on the right. In an equilibrium involving gases, an increase in pressure favours the reaction which produces the smallest number of molecules. In this case, an increase in pressure favours the forward reaction, and more ammonia is produced.

The reaction never goes to depletion, the reactants are not all used up. This is because ammonia molecules collied and break down under the same conditions which is the revers reaction. In this reverse reaction mixture, these two competing reactions are going on at the same time. As the reaction is being proceeded, a dynamic equilibrium is reached. Ammonia molecules are breaking down as fast as they are being formed. But the rate of the forward reaction is same as the rate of the reverse reaction.

The condition used in Haber’ process are: Nitrogen and Hydrogen are mixed in a ratio of 3:1; an optimum temperature of 450 degrees celsius is chosen; a pressure of 200 atmosphere is applied; a catalyst of finely divided iron is used; the ammonia is condensed out of the reaction mixture and the remaining Nitrogen and Hydrogen recycled.