A Study of Bubble Mineralization by Modified Glass Microspheres Based on a High-Speed Dynamic Microscopic Test System

Abstract

The microscopic study of bubble mineralization is an important means of flotation theory research. In order to visualize the research process, it is required that the particles have certain optical properties and the amount of bubbles is controllable. In this paper, the particles were glass microspheres modified with trimethylchlorosilane (TMCS). The modification effect was confirmed by Fourier-transform infrared spectroscopy (FTIR), contact angle measurements, and a flotation test. The FTIR analysis and flotation test verified that the functional group (-OH) of glass microspheres reacted with the functional group (-Si-Cl) of TMCS and that the glass microsphere surface was successfully modified. The results also showed that the contact angle and hydrophobicity of the glass microspheres of a given size increased with the increase of TMCS. A small glass microsphere required more TMCS during the modification step in order to have the same contact angle as a large glass microsphere. The microscopic process of bubble mineralization was captured by a high-speed dynamic analysis system. The probability of collision between large glass microspheres and bubbles was high, but so was the probability that the microspheres would detach from the bubble. Both the collision probability and the detachment probability between small glass microspheres and bubbles were small, and small glass microspheres were easily affected by the flotation fluid. Besides, small bubbles and fine glass microspheres had a higher flotation recovery than coarse glass microspheres and large bubbles.