Sulfur production in the United States

[1] Byproduct sulfur from oil refineries, gas processing plants, and metal smelters is a "nondiscretionary byproduct," meaning that the sulfur recovery is mandated by environmental regulations put in place to prevent air pollution.

The largest market in the US is in the manufacture of fertilizers, which makes up about two-thirds of consumption.

The Frasch process was first used in 1894 in Louisiana, and in the early 1900s came into wide use in mining native sulfur deposits, especially deposits in the caprock of salt domes along the Gulf Coast of the United States.

In many ores of copper, zinc, lead, and molybdenum, the metals are in the form of sulfide minerals.

These include the principal ore minerals of copper (chalcocite, chalcopyrite), zinc (sphalerite), lead (galena), and molybdenum (molybdenite).

The sulfur is present in the form of hydrogen sulfide, a toxic gas that must be removed for safety reasons.