Patent ID: 9441283
Filing Date: 2016-09-13
CPC Classification: C01F,C01G,C01P,C22B

Claim Text:
1. A method for processing bauxite, comprising: grinding the bauxite using a circulating chelate solution and heating the ground bauxite solution to extract iron and form a pulp comprising an iron chelate and an aluminium chelate; separating the pulp into a solid phase enriched in bauxite and into a liquid phase comprising the iron chelate; extracting aluminium from the liquid phase at a pH of about 7 to about 8 using circulating sodium hydrogen carbonate to form a precipitate of sodium hydrogen carboaluminate and a neutralized pulp, separating the precipitate of sodium hydrogen carboaluminate from the neutralized pulp to form a neutralized liquid phase; extracting iron from the neutralized liquid phase at a pH of at least about 12 using a hydroxide composition to form a precipitate of iron hydroxide and a basic pulp; separating the precipitate of iron hydroxide from the basic pulp to form an iron ore concentrate and a mother liquor chelate; concentrating the mother liquor chelate by evaporation; cooling the concentrated mother liquor chelate; carbonizing the cooled concentrated mother liquor chelate with gaseous carbon dioxide under pressure to crystallize sodium hydrogen carbonate; and separating the crystallized sodium hydrogen carbonate from the carbonized cooled concentrated mother liquor chelate to form a chelate liquid phase and a sodium hydrogen carbonate solid phase.