school of Chemical & Environmental Engineering,China University of Mining and Technology ( Beijing)

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:p H值在7左右、硅酸钠用量为1 000 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,p H值为中性时,煤和高岭石表面电位分别降低了6 m V和16 m V;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 e V,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。

in order to study the mechanism of selective inhilbiion of sodiunm sliate on cay minerals the fctaion behavior of coal and laoinite ith sodum silicaewere investigated by fiotation test.Zeta potential test and XPS analysis . The fotation experimentrsuls show that the separcaionefec isthe best.the recovery of cal s 60.44% and the ash content is 8.03% with 1 0o g /t NasSi0g in the p H of 7.TheZetapotentials of coal and laolinteshft egative y and the el crostatc repusin between the two minerals increase in presence of sodium slialte. The sufacepotential of coal and kaolin te decreases 6 m v and '16 m V with neuralp . The resits of PS show that the relative content of Si on the surface of coal and kaolite increases with sodium silicae,the decrement of Si 2p inding enegy of cal and caol ilie is-0. 2 e v and-0.19 e v respectivly.Accarding to the resuts of P it can be concluded that sodum sili ate is absored on the surace of coal and kaoinie by physical adsorption,the different adsorption capacity of the two minerals makes sodium silicate own selective inhibition

国家重点基础研究发展计划(973计划)资助项目(2012CB214901)；国家自然科学基金资助项目(51404274)；