Why are h2s, mercaptans, sulphur compounds and salt removed from the crude oils?

Answer & Explanation:

1- The sulfur present in the crude oil can poison the catalysts that are used in the refining of crude oil into the many useful products obtained from crude oil.

2- The crude oil, containing sulfur compounds, introduced into a car or truck engine, it will again interfere with the catalytic converter installed in the exhaust system of the vehicle.

3-  if sulfur is present in fuel, when the fuel is burned it will be converted to SO₂ which is a known precursor to acid rain.

4- Sulfur compounds can lead to increased corrosion in distillation equipment at the high temperatures used.