Surface chemistry aspects of coal flotation in bore water
Surface chemistry aspects of coal flotation in bore water
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DOI：
10.1016/j.minpro.2009.04.001
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发表时间：
2009-08-01
影响因子：
--
通讯作者：
Nguyen, A. V.
中科院分区：
文献类型：
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作者：
Ozdemir, O.;Taran, E.;Nguyen, A. V.
关于盐溶液中煤的强化浮选，人们提出了几种理论解释。在这篇论文中。通过气泡-颗粒吸附时间实验、Zeta电位测量、接触角循环测量和原子力显微镜(AFM)研究了煤在钻孔(高盐度)水中浮选的表面化学特性。附着时间实验表明，气泡-颗粒在去离子水中的附着是瞬时的，与颗粒大小无关。在钻孔水中的附着时间较长，且随颗粒大小的增加而增加。对平坦煤表面接触角的循环测量表明，在盐离子存在的情况下，以推进(最大)和后退(最小)接触角衡量的煤的疏水性没有变化。Zeta电位测量表明，煤颗粒和气泡在钻孔水中都带有负电荷。AFM研究表明，钻孔水降低了煤粒与气泡之间的排斥表面力，但对粘附力影响不大。总体结果表明，煤在高盐度水中的强化浮选并非完全归因于表面化学方面的原因。(C)2009爱思唯尔B.V.保留所有权利。
Several theories have been proposed to explain enhancement of coal flotation in salt solutions. In this paper. surface chemistry aspects of coal flotation in bore (hypersaline) water were examined using bubble-particle attachment time experiments, zeta potential measurements, cyclic measurements of contact angle and Atomic Force Microscopy (AFM). The attachment time experiments showed that the bubble-particle attachment in deionized water was instantaneous and independent of the particle size. The attachment in bore water required longer time, which increased with increasing particle size. The cyclic measurements of contact angle on a flat coal surface showed that the coal hydrophobicity as measured by the advancing (maximum) and receding (minimum) contact angle did not change in the presence of salt ions. The zeta potential measurements show that both the coal particles and air bubbles were negatively charged in bore water. The AFM studies showed that bore water reduced repulsive surface forces between the coal particles and air bubbles but had little effect on the force of adhesion. The overall results suggest that enhancement of coal flotation in hypersaline water is not entirely attributed to the surface chemistry aspects as previously proposed. (C) 2009 Elsevier B.V. All rights reserved.