可溶性淀粉在长石与石英浮选分离中的作用

通过单矿物浮选实验、动电位测试及吸附量的测定，揭示了可溶性淀粉在长石与石英浮选分离中的作用。结果表明：采用十二胺（DDA）和十二烷基磺酸钠(SDS)作为混合捕收剂，可溶性淀粉对长石与石英皆有抑制作用，相对而言可溶性淀粉对石英的抑制作用较强，对长石的抑制作用较弱；动电位测试表明，长石在可溶性淀粉中的zeta电位相对于在纯水中的zeta电位只是略微向正方向移动，pH值为 5～7的范围内，石英在可溶性淀粉溶液中的zeta电位明显向正方向移动；吸附量的测定结果表明，在中性矿浆条件下，淀粉用量在20-80 mg/L的范围内，其在石英表面的吸附量大于在长石表面的吸附量，淀粉阻碍了捕收剂在石英表面的吸附，因此淀粉能够有效地抑制石英，而对长石抑制作用较弱。

Role of Soluble Starch in the Flotation Separation of Feldspar and Quartz

The role of soluble starch in the flotation separation of feldspar from quartz was revealed through the single mineral flotation test, potentiodynamic test and absorption measurement. The results showed that soluble starch inhibited the flotation of feldspar and quartz when dodecylamine (DDA) and sodium dodecyl sulfonate (SDS) were used as mixed collectors. Compared to feldspar, the inhibition effect of soluble starch on quartz was stronger. The results of potentiodynamic test showed that the zeta potential of feldspar in soluble starch solution slightly shifted to the positive direction compared to that in pure water. However, the zeta potential of quartz in the soluble starch solution significantly shifted to the positive direction compared to that in pure water in the pH range of 5 to 7. The results of absorption measurement showed that when the dosage of starch was in the range of 20-80 mg/L, the adsorption capacity of quartz on the starch was larger than that of feldspar under the neutral pulp conditions. These results demonstrated that starch could hinder the adsorption of the collector on the quartz, and thus effectively depress the flotation of quartz. By contrast, the inhibition of starch on feldspar was weaker.