加圧選鉱法による微細な石英とディッカイトの分離

Abstract

The flotation separation of dickite and quartz finer than 2 μm has been investigated by using a pressure type and a Denver type flotators. Flotation tests were carried out by activating dickite with calcium chloride, followed by adding sodium oleate as a collector.In Denver type flotation, the separation of dickite from quartz can be achieved by the addition of large amounts of calcium chloride and sodium oleate, in neutral pH region. However, in the case of pressure type flotation, dickite can be seiectively floated from quartz by adding Separan AP30 (an anionic polymeric flocculant) and sodium oleate in the presence of proper amounts of calcium chloride at pH 5 to 12. The amounts of calcium chloride and sodium oleate necessary for floating dickite in pressure type fiotation are one tenth and one fortieth, respectively, of those in Denver type flotation.The amounts of calcium ions adsorbed on dickite are larger than those on quartz in neutral to weakly alkaline pH region. The lower the calcium concentration is and the lower the pH value is, the more remarkable the difference in calcium adsorption between dickite and quartz becomes.It is considered from the above results that in pressure type flotation dickite is selectively floated from quartz by the following mechanism: preferential adsorption of calcium species on the dickite surface occurs on the addition of proper amounts of calcium chloride in moderate pH region and induces the adsorption of Separan AP30 and oleate ion by which dickite flocs are formed and the surface becomes hydrophobic.