Efficiency of oxide compounds of magnesium in purification of alumina industry solutions from organic impurities

摘要

The Bayer process aluminate solutions are characterized by accumulation of organic compounds, which worsen the manufacturing parameters and quality of produced alumina. Sorption methods of purification are the easiest and the most efficient. Sorption characteristics of activated carbon, magnesium oxide, hydrated carboaluminates and sulfoalumi-nates of magnesium are considered, concerning organic chemistry of aluminate solutions. Extra-sorbtion mechanism was defined during the processing of aluminate solutions by activated magnesia. There was also defined the high sorption potential of magnesium hydroaluminate phases. Advantages of such compounds consist in the following factors:- likeness of sorbent composition to the system;- absence of influence on solution's technological structure;- low power expenses for reagent regeneration (at the temperatures of 250-400℃). The foregoing characteristics of synthesized sorbents can be the basis for development of technology of aluminate solutions purification from organic compounds by active sorbents (hydrated carboaluminates and sulfoaluminates of magnesium).