Selective Removal Of Mixed Salt Ions By Membrane Technology

This paper is closely focused on separation of ions, ion concentra-tion and desalination using membrane technology. This paper mainly introduces the application of membrane process to removing of impurities of the zinc electrolyte in the hydrometallurgical process and the removal of monovalent and divalent ions in acid red 18. To remove chloride ion from spent zinc electrolyte, nanofiltration membrane process, electro dialysis method and diffusion dialysis method are used to remove the monovalent anions in the zinc electrolyte. In addition, the advantages and disadvantages of these methods in the process of removing chlorine from the zinc electrolyte were compared. At the same time, the mechanism of ion transfer in diffusion dialysis was investigated. In the process of dye desalination, the removal of chloride ion and sulfate ion from the high concentration of acid red 18 dye can be effectively removed using nanofiltration technology, which can effectively remove the monovalent and divalent inorganic ions.The advantages and disadvantages of these three methods are compared with the experimental data. Especially in the study of ion transport mechanism in the diffusion dialysis process, it is found that monovalent Cl- and F- are more likely to pass through ion exchange membranes than HS04-. This finding has not been reported in other works.At the same time, the high velocity using diffusion dialysis treatment electrolyte process is not yet reported in other work, efficiency of chloride ion leakage rate in the range of 5.778 LPH-0.390 LPH was also investigated. Secondly, ionic charge and ionic radius are also taken into consideration in ion permselectivity. The work do not propose an edulcoration method for zinc hydrometallurgical industry, but offer the diffusion dialysis method using in electrolyte in addition to the application of the complex further understanding, especially proposing in-depth detail to the mechanism of the traditional diffusion dialysis. At the same time as the diffusion dialysis method will be further investigated to provide electrolyte impurity an opportunity.Secondly, in the application of nanofiltration technology in ion separation are also explored, mainly study the separation of small molecule inorganic salt and acid red 18 dye molecules. The suitable nanofiltration membranes can effectively separate monovalent and divalent inorganic salt ion from acid red 18. Permeate flux decrease along with the decreasing of salt concentrate.