Chromium potassium sulfate dodecahydrate

Chemical Properties

deep violet-red crystals

Uses

Chromium(III) potassium sulfate dodecahydrate [KCr(SO₄)₂.12H₂O] has been used for the dissolution of gelatin in various studies.
It may be used as a starting material in the synthesis of quasi-monodisperse spherical core-shell particles of Cr/α-Cr₂O₃ to be used as solar absorbers.

Uses

Chromium potassium sulfate dodecahydrate is used in method for synthesizing metal-organic terephthalate structure MIL-101 (Cr).

Uses

Chromium potassium sulfate dodecahydrate is used in preparation of chromium standard solutions.

General Description

Chromium(III) potassium sulfate dodecahydrate (Potassium chromium(III) sulfate dodecahydrate, Chrome alum) is a violet colored solid. It has been synthesized by reacting sulfur dioxide with potassium dichromate (diisolved in sulfuric acid) at -38°C. It is widely used chemical in dyeing and textile industry.

reaction suitability

reagent type: catalyst
core: chromium

Synthesis

After dissolving 98% potassium dichromate and 98% sulfuric acid in the mother liquor of chromium alum according to the theoretical amount, wood chips were added slowly under stirring for reduction. The reaction temperature is controlled at not more than 80C. After the reaction, it is left to crystallize slowly, and after centrifugal separation of the mother liquor, the crystals are washed with a small amount of cold water, and then dried at a low temperature to produce the finished product of chromium potassium sulfate. The reaction formula is as follows:

2K2Cr2O7+8H2SO4+40H2O+3C4KCr(SO4)2-21H2O+3CO2

Purification Methods

Crystallise it from hot water (2mL/g) by cooling.