Surfactant sodium alcohol ether carboxylate(AEC-9Na)was added to the magnesium sulfate solution in order to enhance the leaching efficiency of ionic rare earth ore,and the mechanism of action for AEC-9Na was elucidate...Surfactant sodium alcohol ether carboxylate(AEC-9Na)was added to the magnesium sulfate solution in order to enhance the leaching efficiency of ionic rare earth ore,and the mechanism of action for AEC-9Na was elucidated.Under optimal conditions,the addition of AEC-9Na with a mass fraction of 0.03% can enhance the leaching rate by 5.2% and reduce the leaching cycle.Kinetic analysis demonstrates that the leaching process follows the model of internal diffusion control.The analysis of the mass transfer process reveals that the addition of AEC-9Na results in a decrease in the height equivalent to a theoretical plate(HETP)and an improvement in mass transfer efficiency.The addition of AEC-9Na can reduce the thickness of the water layer adsorbed on particles during leaching,which in turn reduces hydration and facilitates penetration of the leaching solution into ore body pores.This improves mass transfer concentration differences during leaching,and facilitates desorption of rare earth ions.Periodic density functional theory(DFT)calculations show that the adsorption of AEC-9Na onto the surface of kaolinite(001)enhances the hydrophilicity of the mineral surface and improves its permeability efficiency.Simultaneously,AEC-9Na forms complexes with hydrated rare earth ions on the kaolinite(001)surface,thereby reducing their adsorption strength on clay minerals.This promotes the exchange and desorption process of magnesium ions to hydrated rare earth ions,ultimately enhancing the mass transfer process for leaching rare earth elements.展开更多
基金Project supported by the National Natural Science Foundation Regional Innovation Development Joint Fund(U24A2096)。
文摘Surfactant sodium alcohol ether carboxylate(AEC-9Na)was added to the magnesium sulfate solution in order to enhance the leaching efficiency of ionic rare earth ore,and the mechanism of action for AEC-9Na was elucidated.Under optimal conditions,the addition of AEC-9Na with a mass fraction of 0.03% can enhance the leaching rate by 5.2% and reduce the leaching cycle.Kinetic analysis demonstrates that the leaching process follows the model of internal diffusion control.The analysis of the mass transfer process reveals that the addition of AEC-9Na results in a decrease in the height equivalent to a theoretical plate(HETP)and an improvement in mass transfer efficiency.The addition of AEC-9Na can reduce the thickness of the water layer adsorbed on particles during leaching,which in turn reduces hydration and facilitates penetration of the leaching solution into ore body pores.This improves mass transfer concentration differences during leaching,and facilitates desorption of rare earth ions.Periodic density functional theory(DFT)calculations show that the adsorption of AEC-9Na onto the surface of kaolinite(001)enhances the hydrophilicity of the mineral surface and improves its permeability efficiency.Simultaneously,AEC-9Na forms complexes with hydrated rare earth ions on the kaolinite(001)surface,thereby reducing their adsorption strength on clay minerals.This promotes the exchange and desorption process of magnesium ions to hydrated rare earth ions,ultimately enhancing the mass transfer process for leaching rare earth elements.
