Molecular Simulation Study On The Adsorption Of Sodium Oleate On The Surface Of Hematite Flocs

The flocculation flotation of fine-grained hematite is one of the most effective methods for some complex and difficult-to-separate fine-grained hematite.Although the flocculation and flotation of fine-grained hematite technology has made achievements in the field of beneficiation,with the improvement of flotation theory,research The level can't just stop at changing the parameter conditions and the influence of the type of agent on the recovery rate of minerals.Molecular simulation is a novel research method.It has the characteristics of simplicity,easy operation,and convenience without the cumbersome process flow.It can visually show the adsorption method and adsorption process of the agent and mineral in the system from the microscopic field,which will help deepen the research.The understanding of the flotation mechanism.Based on the first principles,through the use of quantum chemistry software,considering the properties and crystal structure of hematite,the modeling and optimization calculation of hematite flocs found that the cutoff energy of crystals and related functionals have an effect on the flocs.Construction has a clear impact.And through research,it is found that when the relevant functional EXC[?] is GGA-PBE and the cut-off energy is 340 e V,the energy of the crystal structure is the lowest,and the lowest is-6073.75 e V.The calculated energy band and density of states of hematite flocs are studied and analyzed.It is found that in the crystal structure of hematite near the Fermi level,the density of states is mainly contributed by O2 p and Fe3 d,of which Fe3 d orbital contributes the most.Available Fe and O atoms are active sites on the surface of hematite;The analysis of the molecular dynamics simulation results of calculating water and flocs found that the atomic density distribution shows that the arrangement of water molecules at the floc/water interface in the system is more orderly than the water molecules far away from the mineral surface.In the competitive adsorption of water molecules and sodium oleate,it was found that the adsorption energy of a single water molecule on the flocs was-5.8kcal/mol.The interaction energy of sodium oleate on the surface of hematite flocs in the system is-9.64kcal/mol,which is greater than the energy of the hydration layer formed on the surface of the flocs,which indicates that sodium oleate can penetrate the hydration layer and be stably adsorbed on the flocs surface.Using COMPASS?phyllosilicates force field to study the adsorption of different concentrations of sodium oleate on the hematite floc/water interface,the results show that sodium oleate is adsorbed on the surface of hematite flocs in a single layer,which is less affected by water molecules.Sodium oleate ions can be stably adsorbed on the surface of the floc through hydrogen bonding.If the concentration of the collector in the system increases,the adsorption energy of sodium oleate on the surface of the floc will gradually increase,which shows that In the high-concentration collector system,it is more conducive to the adsorption of sodium oleate on the floc surface.Through the analysis of hydrogen bond,radial distribution function,adsorption site and hydration energy,the mechanism of interaction between sodium oleate and hematite flocs is explored,providing theoretical support for guiding practical production and application.Figure55;Table13;Reference75...