砷黄铁矿硫化钠诱导浮选的研究

研究了减性介质中硫化钠作还原电位调整剂时砷黄铁矿的无捕收剂浮选,即硫化钠诱导浮选。普通还原剂S_xO_y~(2-)(如S_2O_4~(2-)、S_2O_3~(2-)、SO_3~(2-))调控矿浆电位时,砷黄铁矿无捕收剂浮选行为较差;而用硫化钠调控电位时,浮选行为明显得到改善,矿浆电位下限降低。这表明HS~-离子在降低矿浆电位同时,还能增加砷黄铁矿表面的疏水性。通过矿浆电位测量,HS~-离子在砷黄铁矿表面吸附量测定,中性硫的溶剂提取-化学分析,研究了HS~-离子的上述两种作用。结果表明,砷黄铁矿经硫化钠调浆后矿浆的铂电极静电位丁降不大,HS~-离子能在砷黄铁矿表面发生电化学吸附而生成疏水中性硫。

AN INVESTIGATION ON THE SODIUM SULFIDEINDUCED FLOTATION OF ARSENOPYRITE

The collectorless flotation of arsenopyrite in the presence of sodium sulfide,that is,sodium sulfide-induced flotation,was investigated.When pulp potential was controlled byS_xO_y~(2-) such as S_2O_4~(2-),S_2O_3~(-2) and SO_3~-,the collectorless flotation in lkaline media was poor.But when Na_2S was used to control pulp potential,the flotation was reatly improved.Thisshowes that HS~- ion action has two aspects:reducing the pulp potential nd endering themineral hydrophobic.The two actions were studied by measuring the pulp potential nd ad-sorption density of HS~- ion at the mineral surface,and using solvent extraction-hemicalanalysis method.The results show that the rest potentials of platinum electrode in the r-senopyrite pulp containing Na_2S are higher.The electrochemical adsorption of HS~- ion tookplace and resulted in the formation of neutral sulphur.