利用钠盐助磨剂制备超细黄铁矿粉体的界面光学特性

Interfacial and optical characteristics of pyrite ultrafine powder prepared using sodium salts as grinding additives

以超细黄铁矿粉体为研究对象,利用吸光度法研究黄铁矿在液相中添加六偏磷酸钠、油酸钠、硅酸钠、多聚磷酸钠、十二烷基硫酸钠后的分散性。研究结果表明:含有表面活性基团的油酸钠和十二烷基硫酸钠对于黄铁矿具有较好的分散效果。对这2种效果较好的添加剂的分散条件如pH、超声时间的影响进行分析,并对黄铁矿在这两种添加剂中的界面性质包括沉降曲线、表面电位和润湿性进行研究。在此基础上,用红外光谱对油酸钠和十二烷基硫酸钠作为助磨剂时制备黄铁矿超细粉体的光学性质结合扫描电镜进行研究,结果表明在研磨过程中黄铁矿粉体有部分硫被氧化成硫酸根,油酸钠与十二烷基硫酸钠助磨剂的使用有利于降低黄铁矿研磨过程中的氧化程度。

Using pyrite ultrafine powder as the object of this work,the dispersion of pyrite in different sodium salt additives such as sodium hexametaphosphate,sodium oleate,sodium silicate,sodium polyphosphate,and sodium dodecyl sulfate was analyzed with spectrometry.The results indicate that two surfactants namely sodium dodecyl sulfate and sodium oleate show better disperisibility for pyrite.The effects of some dispersion conditions such as pH and ultronication time on the disperisibility of dium dodecyl sulfate and sodium oleate were analyzed.The interfacial properties of pyrite dispersed in sodium dodecyl sulfate and sodium oleate solutions were investigated with precipitation curve,zeta potentiometry,and wettability.Based on these results,pyrite ultrafine powder was prepared using sodium dodecyl sulfate and sodium oleate as grinding additives,whose optical characteristics were studied by FTIR spectrometry in cooperation with scanning electron microscopy.The FTIR spectra indicate that although some parts of sulfur in pyrite are oxidized into sulfate during the grinding,sodium dodecyl sulfate and sodium oleate can reduce the oxidation degree of pyrite.