A Study On Lead Recover From Spent Lead Acid Batteries By Solid State Electrolysis

Having excellent recycling ability,safety and many other advantages,lead-acid battery plays an important role in many fields.However,a huge amount of spent lead acid batteries pose a great threat to environment safety and human health recent years.Therefore,the spent lead acid batteries,as important secondary resource,are supposed to be recovered properly for reuse.In order to reduce both the cost of recovering lead by electrochemical process and the risk of secondary pollution,research of a new process of lead recover from spent lead acid batteries by solid state electrolysis through electrolytic experiments,electrochemical analysis,numerical simulation and other methods is reported in this paper where the effects of electrolysis process parameters and electrolyte components on the electrolysis process were expounded and the methods to improve the electrolysis effect were studied,of which the main contents include the following three aspects:(1)Influence of different process parameters on the process of lead recover from spent lead acid batteries by solid state electrolysisBased on the analysis of the components and properties of waste lead paste,it was found by electrolysis experiment that the energy consumption of the electrolysis process was influenced by the constituents and the weight of spent lead paste,the plate distance and the electrolysis device structure.The lead paste from positive electrodes and negative electrodes were supposed to be disposed separately.The device cathode could be fitted with a stainless steel perforated plate;When the weight of lead paste was 8 kilogram per square meter and the plate distance was 10-15 millimeter,the best electrolysis effect could be achieved,in which case the cathode current efficient was more than 90% and the energy consumption of per ton of waste lead paste recovery was only 352 KWH.(2)Influence of the electrolyte components on its properties and electrolytic reactionsIt was found through electrochemical analysis and other methods that the electrochemical performance of ammonia sulfate solution as electrolyte was better than that of sulfuric acid;Two kinds of surfactants,polyoxyethylene sorbitan monolaurate(tween-20)and tetrabutylammonium bromide(TBAB),could increase the limit current density and optimize the reduction process of the electrolysis process respectively,and the best work effect could be achieved when they were used both.(3)Multiphysical field simulation and parameters optimization of the solid state electrolysis of waste lead pasteMultiphysical field model was established to simulate the electrolysis process,from which it was found that porous substrate with smaller thickness was more suitable for the electrolysis reaction,and 5.0 millimeters was the optimal value of thickness;With the increase of initial porosity of porous substrate,the effect of the electrolytic reaction first increased and then decreased,and 0.55 was the optimal innitial porosity;The current density of the electrolytic process increased with the exchange current density of the reaction on anode surface,which means anode electrodes of which the material or coating was with high oxygen evolution electrocatalytic activity were supposed to be used.