Study On The Separation And Recovery Technic Of Nickel,Cadmium And Cobalt From Spent Rechargeable Battery

For resolving the pollution of discard rechargeable battery and the recovery technology of precious metal such as Ni, Cd, Co, the thesis put forward one pretreatment technicalroute of discard battery and three kinds of hydrometallurgy technical routes to separate and recover Ni,Cd,Co from spent battery on the bases of optimizing experiments of technical conditions and theoretic analysis. The best technology is selected by Comparison. Interaction model was established for predicting the extraction system.The three kinds of technologies use common industrial extractants. Under the optimal conditions (separation process, concentration and pH of solution, ratio of organic phase to aqueous phase, operation stages etc), the first way using extractants DEHPA and Cyanex272 extracts and separates Cd,Co,Ni one by one through two extraction operations from sulphuric acid leaching of Ni-Cd-Co-containing residues in spent rechargeable batteries. The extraction efficiencies of Cd, Co, Ni are 99.5%,99.2% and 96.65% respectively; the second way using extractants Cyanex923 and Cyanex272 extracts and separates Cd, Co, Ni one by one through two extraction operations from hydrochloric acid solution. The extraction efficiencies of Cd, Co, Ni are 98.6%, 96.6% and 98.0% respectively; the third way using extractant LIX84 through oxidation, extraction and sedimentation extracts and separates Co, Ni, Cd one by one from ammoniac salvolatile solution. The extraction efficiencies of Co,Ni,Cd,are 99.9%,98.2%and 98.5% respectively. Through comparing the three flows above it, because of the advantages such as high separation efficiency, simple craft, easy operation, lesser and circling use of the extractant, lower production cost, without new pollutions et al., the third technology is the best one.Interaction model was established for the extraction. It was shown that the linear model, without interaction parameters, is not suitable for the complex system containing metals Nickel,Cadmium and Cobalt. The addition of interaction parameters will give out good prediction of the corresponding extraction behavior. The four-dimensional mathematics model with interaction parameters can be use to offer reference for the technology design and control in future.