Abstract: In order to clarify the effect of heating on fluorite flotation characteristics,quantum chemistry and molecular dynamics calculations were used to simulate the dissolution behavior of calcium points on fluorite surface and the influence of heating on fluorite flotation behavior.Through pure mineral flotation tests,determination of calcium ion dissolution,oleate adsorption and atomic abundance on fluorite surface,the influence of temperature on the flotation characteristics of fluorite was further analyzed.The results showed that:① The main adsorption site of oleate on fluorite surface is calcium point,and the adsorption mode is chemical adsorption.The adsorption is stable at room temperature and the adsorbed oleate cannot easily enter the liquid phase although the displacement appear due to the atomic relaxation on fluorite surface.② The increase of temperature can promote the dissolution of calcium points on fluorite surface.The higher the temperature is,the more calcium points are dissolved.With the continuous dissolution of calcium points,the adsorption of oleate on the surface of fluorite will also appear desorption phenomenon,so heating has a negative effect on the direct adsorption of oleate on the surface of fluorite,and finally leads to the decline of fluorite flotation recovery rate.

Key words: fluorite,heating flotation,quantum chemistry calculation,molecular dynamics simulation,calcium ion,adsorption capacity