Quantization of the hydration and dodecylamine adsorption characteristics of hematite and quartz surface active sites to forecast the flotation behavior of minerals

The deep integration of modern information technology and mineral processing, the establishment and application of a database, and fast, efficient and accurate selection of beneficiation technology and flotation reagent system, which is a development trend of modern mineral processing. In this study, the flotation system with hematite, quartz and dodecylamine (DDA) as collector was used as an example to quantify the types and densities of active sites on the surfaces of hematite and quartz, as well as the reaction equilibrium constants of their hydration reactions and the adsorption equilibrium constants of DDA. Protonation and adsorption experiments were simulated using the Surface complexation model (SCM) with single site ( ≡SiOH or ≡FeOH ) and monodentate surface complexation. The protonation and adsorption reaction equations were established based on the material and charge equilibrium under experimental conditions, and the equilibrium constants of the surface reactions were obtained by numerical optimization. Results of surface complexation model indicate that the adsorption ability of DDA on the quartz surface is stronger than that of hematite. DDA adsorption can be successfully predicted using SCM in pH and different mineral ratios system. Overall, this work reveals the quantitative expression of the mineral inherent   characteristic and the affinity with reagents, forming a model for predicting the adsorption capacity of the reagent and providing an optimal solution for flotation.