Study On Mechanochemical Activation Of Separation Of Low Grade Assimilable Phosphorite

The techniques of processing phosphorite ore by mechanochemistry were investigated in this paper.The effect of many factors on the activity of apatite was analysed,such as mechanical activation,grinding aid,dry-milling,wet-milling,activator,potassium ore and the calcination.The activation samples were characterized by X-Ray Fluorescence(XRF),Granulometer,Scanning Electron Microscope(SEM),X-Ray Diffraction(XRD),Infrared Spectroscopy,Thermogravimetric-Differential Scanning Calorimetry(TG-DSC),etc.The changes of phase composition,surface topography,crystal structure and microstructure were discussed and also,the changing pattern of the amount of water-soluble phosphorus and assimilable phosphorus was measured by Quimociac Gravimetric method.The mechanochemistry method invloved in this paper has many advantages,such as excluding the operations that involve the use of solvents and gases and the possibility of obtaining a product in the metastabile state which is difficult(or impossible)to obtain using traditional technological methods.The mechanochemistry method refers to the mechanical action,such as friction and impact,which can induce physical chemistry reaction,changes of organization,structure and properties of solid phase.The products modified by this method have a great future potential of industrialization and utility.This paper investigated different phosphorite ore activation conditions,including the mechanical activation,activation with grinding aid,activation with activator and activation with potassium ore,which involved processing parameters,such as activation method,activation time,phosphorite/potassium ratio and calcinationon temperature.The results of experiments indicate that when activated by mechanochemistry method,the leaching rate of water-soluble phosphorus is 9.5%,the leaching rate of assimilable phosphorus is 61.6%;with the calcinationon temperature increase from 200 ? to 600 ?,the leaching rate of assimilable phosphorus increase from 62.1%to 66.6%;when activated with activator,the amount of assimilable phosphorus is 86.2%;when activated with potassium,the amount of assimilable phosphorus is 87.3%;The results of the analysis confirmes that mechanical activation process make apatite grain size decrease,lattice defects,ion replacement and generate new phase,which lead to the activation of apatite.