Research On Recovery And Regeneration Of Anode Materials For Zinc-nickel Batteries

Zinc-nickel battery is a kind of battery with excellent electrochemical performance.The arrival of the zinc-nickel battery application boom will surely attract people's attention to its recycling problems.However,there are few researches on its recycling,and the recycling of zinc negative electrodes is still blank.In this paper,a new idea about zinc-nickel battery recycling and regeneration is put forward by referring to the relevant literature at home and abroad,and the recycling of the zinc anode i n this idea has been systematically studied.Include:Nitric acid leaching of the waste negative anode active material mixed powder,impurity removal,the regeneration and electrochemical performance test of zinc aluminum hydrotalcite and calcium zincate as negative material.?1?Using nitric acid to leaching the mixed powder of waste negative anode active materials.The best process conditions for the leaching process is 80m L/50 g,the temperature is 50?,the reaction time is 90 min,and the liquid-solid ratio is 10:1.Under this condition,the leaching rate of Zn and Cu in the mixed powder of waste anode active material can reach 99.93%and 99.94%,respectively.?2?Two methods of zinc powder replacement and extraction are used to remove the impurity copper ions in the leaching solution.The best process conditions for the process of removing Cu²⁺by zinc powder replacement are:p H=5,the amount of Zn powder is the theoretical amount,the temperature is 70?,and the reaction time is 30min.Under this condition,the removal rate of Cu²⁺in the leaching solution can reach 99.04%.The best process conditions for extracting impurity Cu²⁺are the organic phase concentration of 20%,p H=2.0,comparison 1:1,standing time 3 min and mixing time 5 min.Under this condition,the removal rate of Cu²⁺in the leaching solution can reach 99.2%.?3?Preparation of zinc-aluminum hydrotalcite and calcium zincate were carried out by hydrothermal method or co-precipitation method with the before and after impurity removal,respectively.The result shows that the zinc-aluminum hydrotalcite synthesized by the hydrothermal method has a higher purity than the zinc-aluminum hydrotalcite synthesized by the co-precipitation method,and the zinc-aluminum hydrotalcite prepared after the impurity removal is better than the zinc-aluminum water prepared before the impurity removal on purity.The recyclability and corrosion resistance of the regenerated zinc-aluminum hydrotalcite are better than that of zinc oxide,and the reversibility and corrosion resistance of the zinc-aluminum hydrotalcite cycle prepared by the co-precipitation method under the condition containing Cu²⁺are the best.Recycled calcium zincate has good cycle reversibility but poor corrosion resistance,which is lower than zinc oxide.Cu²⁺has almost no effect on the cycle reversibility of regenerated calcium zincate,but it has a certain improvement in corrosion resistance.