Chromium sulphate basic

Chromium sulphate basic, also known as basic chromium(III) sulfate, is a partially hydrolyzed form of chromium(III) sulfate with the general formula Cr(OH)SO₄ or similar hydrated variants like [Cr(H₂O)₆]³⁺ complexes. It appears as a green crystalline powder, soluble in water, with a pH range of 1.5-2.5 and melting point around 90°C.​

This compound features chromium in the +3 oxidation state, making it less toxic than hexavalent forms, and it forms stable octahedral complexes with sulfate and hydroxide ligands. It is hygroscopic, odorless, and used primarily in leather tanning to fix dyes, improve colorfastness, and as a wood preservative.​

Produced by reacting chromium(III) oxide or hydroxide with sulfuric acid, it serves as a key intermediate in industrial applications requiring controlled chromium delivery