Floatability of Magnesium Carbonates by Sodium Oleate in the Presence of Modifiers

A laboratory study has been carried out on the anionic flotation behavior of magnesium carbonates in the presence of modifying reagents, followed by experiments of adsorption and zeta-potential measurements aimed at their selective separation. Sodium pyrophosphate and sodium hexametaphosphate were found to be strong depressing agents for dolomite in the alkaline region, presenting only a slight action on magnesite flotation. Carboxymethylcellulose also depressed dolomite in the pH range 7.0-12.0, but it did not affect magnesite. The modifying action was attributed to adsorption on sites where calcium exists.