CONICET | Buscador de Institutos y Recursos Humanos

The brines of the South American Puna are riches in valuables ions as lithium, potassium,magnesium, sulphate and others. Among them, lithium has the highest economic value;therefore, its grade and recovery are of interest in the purifications steps of the brine. The firststep, concentration by solar evaporation, involves the precipitation of the ions which formsaturated salts and, in consequence, a mass of crystals impregnated with mother liquor isobtained. This liquor, which impregnates the crystals, is the limited factor in the evaporationlevel when a higher lithium grade is wanted. In this paper a progressive evaporation of brinesfrom the North West of Argentina is analyzed, focused in the lithium recovery from theconcentrated brine. For a given brine, it is shown that when the 64.3% of evaporation in volumeis reached the lithium concentration increases from 900 to 7200 ppm, with a brine yield of the 33.5 % in volume and a lithium recovery of the 28.1%.