sulfide is present in large quantities in crude oil and especially in natural gas. In addition small quantities are dissolved in mineral springs and it is formed as a byproduct in a large number of chemical reactions.

Industrially is mainly manufactured from pure sulfur and pure hydrogen at ca. 350°C in the presence of catalysts, such as cobalt molybdenum oxide on γ-Al₂O₃.

Currently most sulfide is still manufactured using the classical reduction of sodium wlfate with coal:

The reaction is carried out in pot furnaces (low brick-lined hearths with lids), continuous furnaces or rotary plate furnaces. The melt produced in the furnace is mashed with water, the undissolved material removed and the solution concentrated to 60 to 62% by evaporation in cast iron vessels. This concentrated solution solidifies at ca. 90°C.

In addition to the reduction of sodium sulfate, an electrolysis process is operated in which a sodium polysulfide solution (from sodium sulfide solution and sulfur) is reacted with electrolytically produced sodium amalgam. In this reaction sulfur is reduced to sodium sulfide:



Sodium sulfide is also formed by the reaction of hydrogen sulfide with sodium hydroxide.

The reduction of sodium sulfate with gaseous reducing agents such as hydrogen (Sulfigran process, formerly operated in Leverkusen), carbon monoxide or hydrocarbons is no longer of industrial importance.