Ferro Sulphide


Ferro Sulphide comes in two types: Iron (III) (Fe2(SO4)3), and Iron (II) (FeSO4). Ferrous Sulphate compounds are the by-products of the steel finishing process. Prior to coating and plating, steel sheets are passed through pickling baths of sulphuric acid, and then Ferro Sulphide is produced. This by-product can then be used in other manufacturing processes, such as in the reduction of chromate during cement production. Ferro Sulphide can also be used to stain concrete, limestone and sandstone a rust colour (produces a yellowish tint). Woodworkers use Ferro Sulphide solutions to colour maple woods with a silvery hue.


Ferro Sulphide of the Iron (III) variety is yellow in colour and a rhombic crystalline salt that is soluble in water at room temperature. Iron (II), when heated, first loses its water (crystallisation) and then the original green crystals convert to ones that become a dirty-yellow solid. When heated further the solid material releases sulphur dioxide, leaving the reddish-brown iron (III) oxide. Decomposition of the Iron (II) sulphate begins at about 480°C.


During the steel finishing process (prior to the coating and plating) when the steel sheets are passed through pickling baths of sulphuric acid, the liquid heptahydrate of Ferro Sulphide (also called copperas or green vitriol), loses water to form the colourless monohydrate solid. Ferro Sulphide is produced by reactions of sulphuric acid in a hot solution of ferrous sulphate in conjunction with an oxidising agent (such as hydrogen peroxide or nitric acid). The production grade ferrous sulphate is packaged in dry short tons as well as in liquid form, usually packed in 55 gallon drums.


Ferro Sulphide, in alternate forms, is used for dyeing several base materials including wood and stone, and as a coagulant for industrial wastes. Ferro Sulphide is used in pigments and in the pickling baths for aluminium and steel. In medical applications, it is used as an astringent and styptic. Other uses include (in its dry form), animal feed, water treatment, fertiliser and catalysts.

In its moist form uses include iron oxide, water treatment, and catalysts. Together with other iron compounds, ferrous sulphate is used to fortify foods and to treat iron-deficiency anaemia. It has also been applied in the purification of water by flocculation and for phosphate removal in municipal and industrial sewage treatment plants. Other uses include treating wood panels on residential houses.

(FeS) Atomic Numbers 26, 16

Chemical Analysis

Sulphide 30 Sulphide 50
S 28-33% S 45-52%
Fe 65% min Fe 42% min
Si 0.5% max Si 2% max


  • 1mt big bags


  • 2-10mm
  • 10-50mm
  • 20-40mm