A process for beneficiation of andalusite present in a compound containing it, by separation from other silicates by flotation to obtain a concentrate whose andalusite content is higher than 90%. It is characterised in that the process comprises at least the following stages:… a) optional grinding and pulping of the said compound containing andalusite… b) preconditioning of the said compound containing andalusite by maintaining the pH of the aqueous phase of the pulp at a value below 3.50, the solids content in the pulp being higher than 30% (one significant figure);… c) conditioning for at least ten minutes after addition of an alkyl sulphonate;… d) optional dilution of the said pulp to bring it to a solids content of between 15 and 30%… e) flotation by bubbling small air bubbles calibrated in a manner known per se, the actual flotation lasting not more than ten minutes. …??Application to the production of refractory raw materials.
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