Equilibria in industry. (:

For industrial processes which are reversible, such as the haber process, the yield is important, but this is not always the biggest consideration. Think of if you got the biggest yield at a low temperature, but this slowed the reaction way down. Or where the reaction runs, or how much it costs to increase factors like pressure, etc. The conditions often have to be compromised.

Ammonia
Used to make fertilisers, and synthetic materials. It is done at low temperature, as, as Le Chatillier's principle says, 'If a system at equilibrium is disturbed, the equilibrium moves in the direction that tends to reduce the disturbance.', This means that if it is at low temperature, it is exothermic, so low temperatures move the equilibrium to the right, as heat is given out. The reaction is a high pressure, as high pressure forces the molecules to areas with less molecules, which is the side which ammonia is on (in the equation.)

Ethanol is made by hydrating ethene, which is a reversible reaction. Catalyst: phosphoric acid abosrbed on silica. Reactants + Products are all gasesous at the temperature used. It is used at a high pressure, as this will force the equilibrium to the right, as it has fewer molecules. (Kinda like it's looking for more room.) A low temperature forces the equilibrium to the right, to give out heat. excess steam forces it to the right to reducethe steam concentration,however, steam will dilute the catalyst. A low temperature will make it loads slower, costs, and high pressure polymerises.

Methanol: a chemical feedstock. Uses a copper cataylst. Also at low temperature and high presure, because low temperature forces equilibrium to the right, as its exothermic and gives out heat, and high pressure forces the equilibrium to the side with less molecules, (right).

Thoughts?