Abstract:Experiments on Bayer digestion of potassium-bearing bauxite and solution desilication with different concentration of K+ in caustic sodium aluminate solution were carried out. The results show that, in range of 30.19~301.94 g/L, variation of concentration of K+ in caustic sodium aluminate liquor has less effect on extraction efficiency of alumina and N/S of red mud. Entering of K element into liquor cannot be prevented entirely during Bayer digestion process, even apparent extraction efficiency of K2O contained in bauxite can be reduced remarkably with increasing of K+ concentration in caustic sodium aluminate liquor. It is difficult for K+ to replace Na+ and enter into crystal lattice of sodium aluminosilicate hydrate as K+ concentration in solution is not higher than 155.28 g/L, and equilibrium concentration of K+ in plant solution would be much higher than current level. Technological measures for potassium removal should be taken to control increasing concentration of K+ effectively in plant production system.