Study On Desulfuration Of Lead Paste In Waste Lead-acid Battery

Since the French Plante invented the lead-acid battery in 1859,the lead-acid battery has been widely used in various fields of life because of its low price,easy access to raw materials,high discharge voltage,small internal resistance and other characteristics,becoming the most used battery in the world.At present,about 90% of lead is used to make lead-acid batteries.In order to save resources and recycle lead,waste lead-acid batteries become an important source of lead recovery.The biggest difficulty in the recovery of waste lead-acid battery is the recovery and utilization of waste lead paste.The composition and content of waste lead paste,and three kinds of desulfurizers are used to desulfurize waste lead paste is mainly studied in this paper.It includes the following parts:(1)The contents of lead sulfate,lead dioxide,lead oxide and lead in waste lead paste were measured by chemical method.The contents of each component were 55%,29.76%,7.95% and 2.61% respectively.The remaining 4.68% were other impurities without lead.(2)The best reaction conditions are as follows: the ratio of ammonia to lead sulfate is 14,the ratio of liquid to solid is 8,the reaction temperature is 50 ℃,the reaction time is 5h,and the desulfurization rate of waste lead paste is 51.7%.(3)The optimum reaction conditions are as follows: the ratio of triethylamine to lead sulfate is 10,the ratio of liquid to solid is 10,the reaction temperature is 60 ℃,the reaction time is 6h,and the desulfurization rate of waste lead paste is 86.77%.(4)Under the nitrogen atmosphere,ethylenediamine was used to desulfurize the waste lead paste.The optimum reaction conditions were as follows: the ratio of ethylenediamine to lead sulfate was 6,the ratio of liquid to solid was 12,the reaction temperature was 80 ℃,the reaction time was 6h,and the desulfurizing rate of waste lead paste was 73.58%.(5)XRD and SEM were used to analyze the phase and structure of the desulfurized lead paste prepared under the best reaction conditions of different desulfurizers.It was found that the content of lead sulfate in the desulfurized lead paste was greatly reduced,and the lead hydroxide produced was needle like structure.