abstract |
A method for separating a suspension containing gypsum granules and calcium carbonate granules and an aqueous solution, wherein the aqueous solution comprises at least one sodium salt, wherein the aqueous solution has a sodium ion concentration of at least 3 g/L and wherein such method comprises a step of separation by flotation using a collector for the gypsum granules, the collector comprising at least one heteropolar organic surfactant of formula RX, in which: R denotes a hydrocarbon-based chain comprising from 2 to 50 carbon atoms, and the hydrocarbon-based chain is chosen from: a saturated or unsaturated linear alkyl chain, a saturated or unsaturated branched alkyl chain; and X denotes at least one ionizable group selected from the group consisting of: a carboxylic group, a sulfonate group, a sulfate group, a phosphonate group, a phosphate group, and a hydroxamate group. |