Recycling And Application Of Separator From Wasted Lead-Acid Batteries For The Modification Of Polypropylene

The recovery and reuse of waste lead-acid batteries has always been the focus of research and industry.At present,waste lead-acid battery recycling has a relatively complete technology and industry chain,most of the waste lead-acid battery components after dismantling have corresponding recycling system.However,the recycling of lead-acid battery separator,which is called "the third electrode",has not received much attention.In China,there are more than 100,000 tons of waste leadacid battery separators fail to be effectively recycled every year,and most of them can only rely on incineration and landfill treatment,which is not only easy to cause environmental pollution but also cause a waste of resources.At present,the waste lead-acid battery separator materials are mostly composed of UHMWPE and highfilled silica,which has high recycling value added.Based on this,this paper carried out the identification,sorting,cleaning and high-quality utilization of wasted leadacid battery separator.The physical and chemical characteristics of wasted lead-acid battery separator were explored,and the sorting and cleaning technology were investigated.The recycling and high-quality utilization approaches were also studied,which will provide a technical support for the recycling,harmless and high-quality of waste separator.The main research contents and conclusions are as follows:Firstly,the identification and sorting of waste separator crushing materials were studied by spectroscopy in this paper,and the removal technology of heavy metal lead was explored,and its physical and chemical characteristics were systematically analyzed.The waste lead-acid battery separator material is composed of 60% to 65%Si O2,about 20% UHMWPE,10% to 15% oil,which is consistent with typical separator formulations and is difficult to recover directly by simple melt processing methods.Secondly,the processing near melting point combined with LLDPE was used to modify the separator to obtain more uniform phase structure.When the LLDPE content is increased to 50%,the fluidity and processing capacity of the material are improved with a melt flow rate(MFR)value of 1.831 g/10 min.The micropowder can be obtained by means of solid phase mechanical-chemical grinding,and the processing fluidity is further improved.In addition,the modified PE partition possesses an excellent performance to resist molten droplets.Finally,the modified recycled separator material was applied to PP composite to study the influence of different treatment methods on its structure and properties.The results show that the addition of the modified recycled material can enhance the impact resistance and wear resistance of PP with the barely change changed properties of tensile,bending and machining properties.The PP modified by the recycled separator from mechanochemical grinding shows the best comprehensive performance with improved crystallization temperature and melting point.Adding10wt% has the best comprehensive performance,and the impact strength is 29.5%higher than that of pure PP,the wear amount is only 4.68% of pure PP.