Molecular Dynamics Simulation Of Interaction Between Inhibitors And Aluminum Contamination In Ion - Type Rare Earth Ore

Rare earth is the strategic reserve resources of our country, its excellent physical and chemical properties make it widely used in different industries.Since the discover of weathered crust rare-earth in south China in 1970 s,its exploration and research has continued. At present we use chemical leaching method to extract rare-earths,the impurity ions in leach liquor had a great influence on the refining. Every year tens of millions RMB has been lost due to extracting agent emulsification caused by the impurity ions,and the quality of rare-earth is affected significantly.This work focuses on how to reduce the amount of aluminum ions in the leaching liquor solution by physical experiments,and the interaction mechanisms between the suppression aluminum agent and rare earth minerals by molecular dynamic simulation.Upon molecular dynamics simulation, radial distribution function and energy have been analyzed between sulfosalicylic acid and aluminum ions.The largest peak appears in radial distribution function graphon between aluminum ions and sulfosalicyl which means aluminum ions are likely to attach sulfosalicyl, while rare earth ions of lanthanum, yttrium are unlikely to attach it.The interaction energy of sulfosalicyl acid and aluminum ions is 2502 kcal/mol,The interaction energy of sulfosalicyl acid and lanthanum ions is-302 kcal/mol,The interaction energy of sulfosalicyl acid and aluminum ions is-570 kcal/mol.The lower interaction energy the more stable structure. Therefore,the interaction between sulfosalicylic acid and aluminum ions is stronger then those between sulfosalicylic acid and rare-earth ions.The calculations show that the adsorption energy of kaolinite(0 0 1) plan and sulfosalicylic acid is-3251 kal/mol. The radial distribution function between them indicates that sulfosalicylic acid interacts with aluminum ions lattice on the surface of kaolinite.due to is adsorption on aluminum lattice of kaolinite surface.Based on the study of mineral properties of weathered crust rare-earth ores. the best leaching conditions are determined,including:sample mass 200 g,use of columnar leaching methods,ammonium sulfate as leaching agent, concentration of leaching agent 3%,liquid-solid ratio 0.8, flow rate 1.7 ml/min, height of rare-earth are 150 mm,ambient temperature and pressure.At this time the rare earth leaching rate is95%,rare earth ion content of 0.70 g/L in leaching solution, aluminum ion content of390 mg/L.Experiments have been done on different inhibitors which found sulfosalicylic acid, acetylacetone, sodium tartrate are good for aluminum suppression which little effect on the leaching rate.