方铅矿磨矿体系表面电化学性质及其对浮选的影响

Electrochemical properties on surface of galena in grinding system and its influence on flotation

采用电化学测试技术研究方铅矿磨矿体系中磨矿介质类型(瓷介质和铁介质)、机械力以及捕收剂对方铅矿表面电化学性质的影响。研究结果表明:瓷介质中,方铅矿表面会发生适当的氧化反应,有利于方铅矿浮选;增大方铅矿与瓷介质间的机械力,体系的还原性增强,同时削弱矿物表面的氧化反应,给浮选造成一定影响。铁介质中,一方面,由于铁与方铅矿的腐蚀电偶作用增强了体系的还原性,降低了药剂在方铅矿表面的吸附性能,另一方面,由于腐蚀电偶作用产生的铁离子增强了方铅矿表面的亲水性,两方面的影响都不利于方铅矿的浮选;增大方铅矿与铁介质间的机械力,二者之间的腐蚀电偶作用和体系的还原性增强,同样不利于方铅矿浮选。当pH=9时,在瓷介质和铁介质磨矿体系中是否添加捕收剂,对方铅矿表面电化学性质和浮选影响不大。

The effects of the grinding media types, mechanical pressure and collector on the electrochemical properties of the galena surface were studied using electrochemical testing technology. The results show that the grinding system of ceramic media is beneficial to galena flotation because only proper oxidation occurs on galena surface. Meanwhile, increasing mechanical pressure between galena and media, which enhances the reducibility of the system to weaken the oxidation reaction of galena surface, affects the floatability of galena. In iron media grinding system, the corrosion couple action between galena and iron media not only increases the reducibility of the system, which decreases the adsorbability of the collector on the galena surface, but also produces iron ion which enhances the hydrophilicity of galena, and therefore decreases the floatability of galena. With the increase of mechanical pressure, the corrosion couple action between galena and iron is stronger, which is deleterious to galena flotation. When pH=9, adding collector these two types of grinding system espectively, the electrochemical properties of galena surface change little, which implies that the effect of collector on galena flotation is small.