FLOTATION SEPARATION OF HEAVY-METAL IONS COLLECTED BY POTASSIUM LAURATE.

Methods for separation of heavy-metal ions by flotation are based on the use of selective collectors, differences in surface activity of compounds formed by interaction of heavy-metal ions with collectors, and differences in solubility or stability of these compounds. In this paper the authors demonstrate that it is possible in principle to separate ions of certain heavy metals by fractional precipitation with potassium laurate followed by flotation of the precipitated fractions. The experiments were carried out on binary solutions of nickel, cobalt, copper, cadmium, and lead nitrates, containing 10 mg/liter of each metal. The collector was alkaline 0. 38% aqueous potassium laurate solution. The collector was introduced into the test solutions with thorough stirring 1-2 min before the start of flotation. The interaction of the metal ions with potassium laurate was rapid, and was accompanied by formation of stable colloidal solutions. Experimental results are plotted and discussed in terms of practical recommendations.