Zn^(2+)与腐殖酸钠组合抑制剂对萤石、方解石浮选分离的影响及机理研究

Effect and Mechanism of Combined Inhibitor of Zn^(2+)and Sodium Humate on the Flotation Separation of Fluorite and Calcite

常见的方解石型萤石矿由于方解石与萤石表面物理化学性质相似,两者的浮选分离较为困难。本文研究了ZnSO_(4)·7H_(2)O与腐殖酸钠组合抑制剂对萤石和方解石选择性分离浮选的影响,通过吸附量测定、XPS检测、红外光谱分析以及溶液化学计算进行了机理分析。实验结果表明,相比于单一腐殖酸钠抑制剂,当使用腐殖酸钠与ZnSO_(4)·7H_(2)O质量比为3∶1的组合抑制剂且其用量为20 mg/L、油酸钠用量为1.5×10^(-4)mol/L、pH为7的条件下,可使萤石、方解石浮选回收率之差由41.8百分点提高到70.31百分点。腐殖酸钠与Zn^(2+)发生化学反应生成的腐殖酸锌与单一抑制剂相较方解石表面腐殖酸根吸附量有所提高;而萤石表面腐殖酸根吸附量减少,更多活性位点与油酸钠结合,油酸钠的吸附量提高,进而提高了组合抑制剂在两种矿物表面的选择性吸附,最终达到浮选分离的目的。

The common calcite−type fluorite ore is difficult to separate by flotation due to the similar physicochemical properties of the surface of calcite and fluorite.The effect of the combined inhibitors of ZnSO_(4)·7H_(2)O and sodium humate on the selective separation flotation of fluorite and calcite was investigated,and the mechanism was analyzed by adsorption measurement,XPS detection,infrared spectroscopy analysis,and solution chemistry calculation.The experimental results showed that compared with the single sodium humate inhibitor,under the conditions of the combined inhibitors dosage of 20 mg/L when the mass ratio of sodium humate to ZnSO_(4)·7H_(2)O was 3∶1,sodium oleate dosage of 1.5×10^(−4) mol/L and pH 7,the difference of fluorite and calcite flotation recovery was increased from 41.8%to 70.31%.the zinc humate generated by the chemical reaction between sodium humate and Zn2+increased the humate adsorption of the calcite surface compared with the single inhibitor,decreased the humate adsorption of the fluorite surface,increased more active sites on the surface of the fluorite and the sodium oleate adsorption,resulting in improving the selective adsorption of the combination inhibitors on the surface of the two minerals and achieving the purpose of flotation separation.