Wetting, in the most general sense, is the process by which one fluid on a surface is replaced by another fluid. In general practice, wetting refers to the replacement of a gas on a solid surface by a liquid. As a result, the degree to which the mineral is wetted by water is different, and the first is the most intuitive sign of the mineral floatability. For this reason, wetting has been studied more in the basic theory of flotation.
Surfactants change the nature of the solid-liquid system, mainly in the following two aspects:
(1) Adsorption of surfactant on solid surface: The amphiphilic molecules of the surfactant are adsorbed on the solid surface to form an aligned adsorption layer, which reduces the free energy of the interface, thereby effectively changing the wettability of the solid surface. For the collector , at this time, the surfactant is oriented toward the solid with a polar group, the non-polar group is toward the liquid, and the solid surface with the adsorption layer is exposed with a hydrophobic group such as hydrocarbon, which has the characteristics of a low energy surface. , the wettability is greatly reduced, and it is easy to adhere and float. The adsorption of such a surfactant may be physical adsorption or chemical adsorption.
(2) Increasing the wetting ability of the liquid: In the system composed of water and a low-energy solid surface, since the surface tension of water is higher than the critical surface tension of the solid, it cannot be spread. To improve the wetting properties of the system, a wetting surfactant, a wetting agent, is added to the water to allow the water to wet the solids well. The essence of the action is to lower the surface tension of the liquid phase to be less than the critical surface tension of the solid to meet the conditions under which spreading occurs. Therefore, the surface having the strongest surface tension of water is lowered and the active agent also has the best wetting action. In the flotation process, it acts as an inhibitor.
Butyl Rubber Production Line,Waterproof Tape Extruder,Tape Extruder,Tape Production Machine
Hebei Shuangda Rubber & Plastic Machinery Co., Ltd. , https://www.shuangdarubber.com