油酸钠与十二胺作用下黑云母的浮选行为及作用机理研究

通过纯矿物浮选试验,研究了黑云母在油酸钠和十二胺为捕收剂时的浮选行为。结果表明,油酸钠单独作用时,对黑云母基本没有捕收作用;十二胺在强酸性条件下对黑云母有较强捕收作用;二者混合使用对黑云母的捕收作用最强,在中碱性条件下的浮选回收率可达80%以上。Zeta电位、红外光谱测试及溶液化学计算结果表明,十二胺在黑云母表面发生了物理吸附作用;单一油酸钠在黑云母矿物表面不发生吸附作用;十二胺主要以RNH_3~+离子和离子-分子缔合物RNH_3~+·RNH_2的形式吸附于黑云母表面;油酸的水解组分都不与黑云母矿物作用;油酸钠与十二胺水解组分的电性中和,降低了捕收剂的临界胶束浓度,二者的共吸附效应可以改善黑云母表面的疏水性,从而使浮选效果变好。

Flotation Behavior and Mechanism of Biotite with Sodium Oleate and Dodecylamine as Combined Collector

The behavior of biotite with sodium oleate and aodecylamine as combined collector is investigated by the single mineral flotation tests.Biotite can be scarcely collected with sodium oleate alone,while dodecylamine can strongly collect biotite in strongly acidic condition and the combined use have a better collecting effect.The flotation recovery can reach above 80％ under medium alkaline condition.Zeta potential test,IR spectrum analysis,and solution chemistry calculations illustrate that physical adsorption of dodecylamine is occurred on the surface of biotite,and single sodium oleate cannot adsorb on biotite surface.Dodecylamine is absorbed on biotite in the form of RNH3+ ion and ion-molecular association (RNH3+ · RNH2).The hydrolysis component of oleic acid does not have a mineralized interact with biotite;The hydrolysis of components electrical neutralization between sodium oleate and dodecylamine can reduce the critical micelle concentration of collector,and both absorption effects can improve the hydrophobicity of biotite and enhance its flotation effect.