| 摘要 |
In processes for reducing the dissolved inorganic and organic impurities in aqueous lyes in the Bayer process for the manufacture of aluminium hydroxide, the additives used entail cost-intensive process controls and increased lye consumption, thereby raising production costs without necessarily ensuring product quality. These drawbacks may be eliminated by subjecting the impure lye Pv to electrodialysis using at least one anion-permeable membrane and/or one cation-permeable membrane and at least one bipolar water-dissociating membrane with formation of an alkaline lye component Pr which is added to the circulating lye in the Bayer process, and an impurity component V which is removed from the process and discarded. |
