[1] The impurities need to be removed before this lower-quality crude can be refined into petrol, thereby increasing the cost of processing.
This results in a higher-priced gasoline than that made from sweet crude oil.
[1] Current environmental regulations in the United States strictly limit the sulfur content in refined fuels such as diesel and gasoline.
The majority of the sulfur in crude oil occurs bonded to carbon atoms, with a small amount occurring as elemental sulfur in solution and as hydrogen sulfide gas.
At low concentrations the gas gives the oil the smell of rotting eggs.