Which element is extracted from petroleum and natural gas using the Claus process?

The element extracted from petroleum and natural gas using the Claus process is sulfur. The Claus process is an industrial method specifically designed for the recovery of sulfur from hydrogen sulfide (H₂S), a compound often found in natural gas and petroleum. When natural gas is processed, H₂S must be removed for safety and environmental reasons.

In the Claus process, hydrogen sulfide is first oxidized to produce sulfur dioxide (SO₂), which then reacts with more hydrogen sulfide in a series of reactions to produce elemental sulfur. This method is significant in the petroleum refining and natural gas processing industries, as it allows for the effective recovery of sulfur, which is a valuable raw material for various chemical processes, including the production of sulfuric acid.

The other options do not relate to the Claus process. Oxygen, hydrogen, and nitrogen are not extracted using this method, and each of those elements has its own processes for extraction and usage in various industrial applications.