| abstract |
The present invention relates to a process for the production of chromic acid CrO3, of high purity on the basis of the electrochemical principle, the measures to be taken comprising the process steps:… 1. preparation and purification of an aqueous sodium chromate/sodium dichromate solution,… 2. conversion of said sodium chromate/sodium dichromate solution into a sodium dichromate/chromic acid solution,… 3. crystallisation of chromic acid from said sodium chromate/chromic acid solution by evaporation,… 4. separation of the crystallised chromic acid from the mother liquor,… 5. recirculation of the separated mother liquor in the centrifuge. |