Purification Of Reaction Slurry For Aluminum-air Battery

With the extensive use of fossil fuels,leading to the depletion of fossil resources and environmental pollution,looking for sustainable new energy to replace fossil energy has become an urgent need of human society.As a new type of clean energy battery,aluminum air battery has the characteristics of high specific energy,rich aluminum resources,high security and environment friendliness,which has a wide application prospect in underwater power supply,standby power supply,power supply station and communication base station.However,the aluminum air battery with alkaline electrolyte has serious aluminum anode corrosion and voltage lag,and the refined aluminum used for aluminum anode consumes high energy,resulting in high cost of aluminum electricity,which makes it difficult for aluminum air battery to be commercialized.In this paper,the reaction slurry of aluminum air battery is used as raw material.Firstly,the impurities such as P,Ca,Sn and Zn in the reaction slurry are removed by chemical precipitation method.Through the single variable method,the optimal experimental conditions are explored.Under the optimal experimental conditions,the P impurity content in the purified filtrate is 1.45×10-4%.The content of Zn is 1.43×10-4%.The content of Ca was 5.72×10-4%.The content of Sn is 5.59×10-4%.The content of Mg is 3.31×10-4%.Then,using the filtrate as raw material,two kinds of intermediate Al(OH)3 were prepared by seed separation-carbon separation process and coprecipitation process.The effects of the two processes on the morphology and purity of the intermediate Al(OH)3 were explored.The crystal structure of Al(OH)3 prepared by seed separation-carbon separation process was Al2O3·3H2O.The particle size is 0.5～1.8 μm.The decomposition rate and purity were 99.83%and 99.9890%,respectively;Aluminum hydroxide prepared by seed separation-carbon separation process was used as raw material,and aluminum hydroxide prepared by coprecipitation process was stacked with sheet structure,with particle size of 0.2～1 μm.The decomposition rate is 99.32%and the purity is 99.9891%.Finally,aluminum hydroxide was centrifugally washed,dried and ground,and calcined at high temperature α-Al2O3.The purity of the product was 99.9907%and 99.9906%respectively;The particle size is 0.3～0.7μm.The surface of alumina crystal prepared by coprecipitation process is smooth and has relatively good dispersion,realizing 4N gradeα-Al2O3 product preparation.Through the research on the reaction slurry of aluminum air battery,the suitable preparation conditions were explored,and the reaction slurry of aluminum air battery was purified by the circulation increment mode,so as to prepare high value-added product 4N grade α-Al2O3.Becauseα-Al2O3 products have many excellent characteristics,wide application fields and strong market demand,the preparation of high-purity α-Al2O3 products by purifying the reaction slurry of aluminum air battery can improve resource utilization,greatly reduce the cost of aluminum electricity,promote the commercial development of aluminum air battery,alleviate the pressure of resource shortage and environment,and meet the needs of people production and life are of great significance.