Basic chromium sulfate is mainly used for tanning leather. It is the raw material for the production of chromium hydroxide. The dye industry is used to produce reactive black dyes. The printing and dyeing industry uses it as a mordant.
The main production methods of basic chromium sulfate are organic matter reduction and sulfur dioxide reduction. After acidification of sodium dichromate mother liquor with sodium bisulfate solution (40 ~ 42° Be) or sulfuric acid in the reactor lined with lead or lined with glass lined stirring, sucrose reducing agent is slowly added under stirring to reduce hexavalent chromium. At the end of the reaction, the solution is kept boiling, which is conducive to complete reaction. The reaction product is syrup viscous liquid, add water to adjust the solution concentration to 40 ~ 42° Be, after natural cooling, and then freeze to below 10℃ in the cooling crystallizer, make part of sodium sulfate into mirage crystal, after centrifugal separation, liquid basic chromium sulfate product, and then concentrate and dry, solid basic chromium sulfate product.
