Process for the treatment of bauxites

Claim 1

THE PROCESS OF BENEFICIATING INSOLUBLE REFRACTORY MATERIALS AVAILABLE AS A SOURCE OF ALUMINA AND CONTAINING SILICEOUS AND FERRUGINOUS MATERIAL AMONG ITS INSOLUBLE IMPURITIES WHICH COMPRISES CALCINING SAID REFRACTORY MATERIALS IN THE PRESENCE OF A BASIC ALKALINE EARTH COMPOUND ADAPTED TO FORM A WATER SOLUBLE ALUMINATE, THE PROPORTION OF SAID ALKALINE EARTH COMPOUND AND THE ALUMINA BEING APPROXIMATELY EQUIMOLAR, AND THE AMOUNT OF SAID ALKALINE EARTH COMPOUND CORRESPONDING WITH THAT SUFFICIENT FOR PRODUCING THE SAID WATER SOLUBLE ALUMINATE WITHOUT REACTING WITH THE IMPURITIES OF THE MINERAL, THE CALCINATION TEMPERATURE BEING APPROXIMATELY 1000* C. AND ADAPTED TO REACT SAID ALKALINE EARTH COMPOUND AND ALUMINA TO FORM SAID SOLUBLE ALUMINATE SUBSTANTIALLY WITHOUT ANY COLLATERAL REACTION BETWEEN THE SAID ALKALINE EARTH REAGENT AND THE INSOLUBLE IMPURITIES, QUENCHING THE HOT CALCINED MASS IN A RELATIVLEY COLD AQUEOUS SOLUTION AND COMPLETING THE DISSOLUTION OF THE ALUMINATE FROM THE RESIDUAL MAGNETIC IRON OXIDE CONTAINING MATERIAL, AND THEN SEPARATING THE ALUMINATE SOLUTION FROM THE RESIDUAL INSOLUBLE MATERIAL.