Schwefel in Erdöl: Ein problematisches Element?

In November 2002, the tanker Prestige sank west of Spain laden with about 77 000 tons of a heavy oil distillation residue that polluted beaches in Spain and France. The public was warned of its toxic properties, (falsely) said to be due to the sulfur. Sulfur is present in commercial crude oils to the extent of 0.1 – 4 %. It is derived from sulfate ions of sea water. Following reduction, it reacts with matter in sediments, ultimately leading to organic sulfur compounds. The removal of this sulfur is an important industrial process.