Department of Chemical and Materials Engineering, University of Alberta, Edmonton, AB, Canada T6G 2V4.
J Colloid Interface Sci. 2012 Feb 15;368(1):512-20. doi: 10.1016/j.jcis.2011.10.048. Epub 2011 Oct 25.
We have studied the activation kinetics of zinc sulfide (ZnS) using silver as an activator by a quartz crystal microbalance with dissipation (QCM-D). The zinc sulfide coating on QCM-D sensor was shown to have similar crystallographic structure, composition, and surface properties as nature sphalerite through the characterization of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and xanthate adsorption measurement using QCM-D. The activation of ZnS sensor by silver was confirmed by the mass increase in ZnS sensor coupled with subsequent xanthate adsorption during QCM-D measurement, the change of surface wettability, and the presence of Ag(2)S on the surface. Two distinct stages on the silver uptake vs. time curve were identified and fitted well by a logarithmic function for the initial stage and a parabolic law in the later stage, which agrees with the two-stage zinc-silver reaction kinetics reported previously. Argon sputtering followed by XPS measurement on the ZnS surface demonstrated the penetration of silver into the bulk ZnS after activation. The present study is the first of its kind to apply the QCM-D technique to investigate sphalerite activation, which introduces a new in situ approach to investigate surface adsorption and activation in many mineral processes and surface modifications.
我们使用石英晶体微天平（QCM-D）结合耗散研究了银激活的硫化锌（ZnS）的动力学。通过 X 射线衍射（XRD）、X 射线光电子能谱（XPS）和 QCM-D 上的黄原酸盐吸附测量，表明 QCM-D 传感器上的硫化锌涂层具有与自然闪锌矿相似的晶体结构、组成和表面特性。Ag 对 ZnS 传感器的激活通过 ZnS 传感器的质量增加得到证实，同时在 QCM-D 测量过程中伴随着随后的黄原酸盐吸附、表面润湿性的变化以及表面上 Ag2S 的存在。在银吸收随时间的变化曲线上确定了两个明显的阶段，并通过对数函数很好地拟合了初始阶段和后期阶段的抛物线规律，这与之前报道的两阶段锌银反应动力学一致。对 ZnS 表面进行氩溅射和 XPS 测量后，证明了银在激活后已经渗透到大块 ZnS 中。本研究是首次将 QCM-D 技术应用于闪锌矿激活的研究，为许多矿物过程和表面改性中的表面吸附和激活研究引入了一种新的原位方法。
