【作者】 徐东方； 朱书全； 朱志波； 崔浩然；

【Author】 Xu Dongfang;Zhu Shuquan;Zhu Zhibo;Cui Haoran;School of Chemical & Environmental Engineering,China University of Mining and Technology(Beijing);

【机构】 中国矿业大学(北京)化学与环境工程学院；

【摘要】 为深入了解煤泥浮选过程中硅酸钠对黏土矿物的选择性抑制机理,以煤和高岭石为研究对象,通过单矿物浮选试验、Zeta电位测定、X射线光电子能谱(XPS)分析,研究了硅酸钠对煤和高岭石浮选行为的影响。试验结果表明:pH值在7左右、硅酸钠用量为1000 g/t时,煤和高岭石的分离效果最好,煤的可燃体回收率可达60.44%,灰分为8.03%;硅酸钠使煤和高岭石表面电位负移,增大了矿物间的静电斥力,pH值为中性时,煤和高岭石表面电位分别降低了6 mV和16 mV;XPS分析结果显示,与硅酸钠作用后,煤与高岭石表面Si原子相对含量增加,并且硅原子2P原子轨道(Si 2p)结合能变化值分别为-0.02、-0.19 eV,证明了硅酸钠在煤和高岭石表面的吸附为物理吸附,吸附量的不同是造成硅酸钠选择性抑制的主要原因。更多还原

【Abstract】 In order to study the mechanism of selective inhibition of sodium silicate on clay minerals,the flotation behavior of coal and kao-linite with sodium silicate were investigated by flotation test,Zeta potential test and XPS analysis.The flotation experiment results show thatthe separation effect is the best,the recovery of coal is 60.44%and the ash content is 8.03%with 1000 g/t Na₂ SiO₃ in the pH of 7.The Zeta potentials of coal and kaolinite shift negatively and the electrostatic repulsion between the two minerals increase in presence of sodiumsilicate.The surface potential of coal and kaolinite decreases 6 mV and 16 mV with neutral pH.The results of XPS show that the relative content of Si on the surface of coal and kaolinite increases with sodium silicate,the decrement of Si 2p binding energy of coal and kaolinite is-0.02 eV and-0.19 eV respectively.According to the results of XPS,it can be concluded diat sodium silicate is absorbed on the sur-face of coal and kaolinite by physical adsorption,the different adsorption capacity of the two minerals makes sodium silicate own selective inhibition.更多还原