Adsorption mechanism of mixed cationic/anionic collectors in feldspar-quartz flotation system
Adsorption mechanism of mixed cationic/anionic collectors in feldspar-quartz flotation system
复制标题
DOI：
10.1016/j.jcis.2006.10.047
复制
发表时间：
2007-02-15
影响因子：
9.9
通讯作者：
Rao, K. Hanumantha
中科院分区：
文献类型：
--
作者：
Vidyadhar, A.;Rao, K. Hanumantha
通过Hallimond浮选、电动力学和漫反射红外光谱研究了酸性条件下烷基二胺阳离子和磺酸盐/油酸盐阴离子混合捕收剂在微斜长石和石英矿物上的吸附机理。在阴离子捕收剂的存在下，两种矿物都不对浮选反应，但观察到矿物的二胺浮选是pH和浓度依赖性的。磺酸盐的存在通过其共吸附作用增强了矿物的二胺浮选。矿物之间的表面电荷在pH 2的差异被认为是在混合的二胺/磺酸盐捕收剂中从石英中优先浮选长石的基础。红外光谱表明，磺酸盐捕收剂单独使用时没有吸附，但与二胺一起使用时显示出二胺-磺酸盐复合物的共吸附。磺酸盐的存在下，增加了二胺的吸附，由于在相邻的表面铵离子之间的静电头-头排斥的减少，从而增加了侧尾-尾疏水键。二元胺/磺酸盐的摩尔比被认为是烷基链取向的重要因素，从而矿物的浮选响应。超过二胺浓度的磺酸盐浓度的增加导致形成可溶的1：2二胺-磺酸盐络合物或沉淀物，并且这些物质的吸附降低了浮选，因为烷基链处于混乱取向，具有指向溶液相的可想象数量的头部基团。(c)2006年爱思唯尔公司All rights reserved.
The adsorption mechanism of mixed cationic alkyl diamine and anionic sulfonate/oleate collectors at acidic pH values was investigated on microcline and quartz minerals through Hallimond flotation, electrokinetic and diffuse reflectance FTIR studies. In the presence of anionic collectors, neither of the minerals responded to flotation but the diamine flotation of the minerals was observed to be pH and concentration dependent. The presence of sulfonate enhanced the diamine flotation of the minerals by its co-adsorption. The difference in surface charge between the minerals at pH 2 was found to be the basis for preferential feldspar flotation from quartz in mixed diamine/sulfonate collectors. The infrared spectra revealed no adsorption of sulfonate collector when used alone but displayed its co-adsorption as diamine-sulfonate complex when used with diamine. The presence of sulfonate increased the diamine adsorption due to a decrease in the electrostatic head-head repulsion between the adjacent surface ammonium ions and thereby increasing the lateral tail-tail hydrophobic bonds. The mole ratio of diamine/sulfonate was found to be an important factor in the orientation of alkyl chains and thus the flotation response of minerals. The increase in sulfonate concentration beyond diamine concentration leads to the formation of soluble 1:2 diamine-sulfonate complex or precipitate and the adsorption of these species decreased the flotation since the alkyl chains are in chaotical orientation with a conceivable number of head groups directing towards the solution phase. (c) 2006 Elsevier Inc. All rights reserved.