The latest application of beverage packaging

New beverage packaging application

steel two-piece cans are a new type of beverage packaging product in China. The research on the shelf life of domestic steel two-piece cans after filling drinks is still blank, which hinders the application of Baosteel tinplate in beverage packaging. In this paper, the corrosion behavior of steel two-piece beverage cans after filling drinks is analyzed, and the linear polarization resistance RP is determined to predict the corrosion electrochemical reaction, taking into account the demand response speed of each entrepreneurial unit. At the same time, the main factors affecting RP measurement are studied accordingly. Moreover, it lays a solid foundation for the rapid prediction of the cargo life of steel two-piece cans with polarization resistance technology in the future. The organic coating on the inner wall of the steel can can prevent the beverage from contacting with the metal surface host at home and abroad, and prevent the metal surface from corrosion. However, in fact, because the organic coating has certain pores, and incomplete defects of the coating may occur during the coating process, the inner coating may also be damaged to varying degrees during the use of steel cans. Therefore, the beverage after filling can directly contact the metal surface through the defects of the inner coating. Hackett's interim report outlines several areas that affect ima's material selection in the renovation of grenfelta, Corrosion occurs, causing iron ions to dissolve into the beverage. The electrochemical reaction of oxidation and reduction occurs after the beverage is filled in the steel can, and its anode and cathode react. The above electrochemical reaction is carried out in aqueous carbonate solution (with a small amount of inorganic salts), and the mass transfer speed is very fast. The gain and loss of electrons in the reaction process is the controlling step of the whole reaction. Therefore, the corrosion reaction after filling drinks in steel cans is an activated polarization control reaction. The reaction rate of this reaction process can be characterized by polarization resistance. High polarization resistance and slow reaction speed; Low polarization resistance and fast reaction speed. 2 theoretical analysis of predicting the precipitation of iron ions in steel cans with polarization resistance RP. since the electrochemical corrosion occurs after the steel cans are filled with beverages, the whole metal cans are regarded as corrosive metal electrodes, and the electrochemical reaction controlled by activated polarization occurs after the steel cans are filled with beverages, And the corrosion potential (-0.68v or so) is not close to the anodic reaction equilibrium potential (the iron oxidation reaction equilibrium potential is -0.44v) and the cathodic reaction equilibrium potential (0V or 0.401v). Therefore, the relationship between the corrosion current icorr and RP of the corrosion reaction in the steel tank can be calculated by formula ⑩. That is, the polarization resistance RP is linearly related to the corrosion current icorr. The precipitation amount of iron ions in beverages can be calculated according to Faraday's Law: when a gram equivalent of oxide is converted into a reducing body, the oxide needs to obtain an electron of Faraday constant from the electrode; When a gram equivalent reducing body is converted into an oxidizing body, the electrode needs to obtain an electron of Faraday constant from the reducing body. Formula 1 can calculate the amount of iron ions in the beverage after a certain time, and can also predict the shelf life of the beverage filled in steel cans