The Reseach On Recycling Of Zinc Chloride Electrolsis

Zinc is widely used in metallurgy, chemistry, medicine, batteries and paints and otherfields. However, as non-ferrous metals zinc, is a non-renewable resources. With the shortageof zinc resources, recycling of secondary resources is a major world environmental theme. Atpresent, the zinc reduction of silicon tetrachloride produced a large number of zinc chloride,and the batter industry, produce large amounts of zinc chloride and zinc oxide, etc., whichoccupy a large amount of zinc, resulting in the use of zinc, is limited. The regeneration ofrecycled of zinc, the main raw material for it based on zinc, zinc oxide, the abandonedgalvanized iron, as raw materials. Take a reasonable method for this process; we can achievethe sustainable development of economic environment. In today’s metallurgical industry, oneof the hot topics of researches is the recovery of the recycled refined metal.In this paper, we take zinc chloride, zinc oxide, zinc hydroxide as raw materials, basedhydrometallurgical process, and combined with the characteristics of raw materials, the use ofelectro-deposition hydrometallurgical recovery of clean prodution processes in the metalscrap zinc and the process of the relevant the cortical basis for a system artic study. Thistechnology has many advantages such as short process flows, less equipment investment, lowenergy consumption, environmental friendly and high metal recycling, and so on. Thesetechnological flows assess the feasibility of technology.Based on the experimental study, the paper offers a new technology. Within the proposedchloride aqueous solution of zinc electrode position, choose the best system to electrodeposition for zinc, NH₄Cl-NaCl-ZnCl₂aqueous solution as the best electro-deposition system,we studied the influence of the composition of the electrolyte, electrode spacing, electrolytetemperature and other factors on the electric current efficiency of zinc deposition. Thismethod uses chlorine over potential anode low RuIrTaTi coated electrode, electrochemistrypolished high-purity aluminum as the cathode, deposition temperature30°C, electrodespacing4cm.Based on the NH₄Cl-NaCl-ZnCl₂aqueous solution as the best electro-deposition system,in the perchloric acid and alcohol electrochemical of4:1, polishing of high-purity aluminum,in the temperature range of10²5°C, at the constant voltage24V, polishing the Al for1min,at this condition, the aluminum, which mixed in the zinc, less than0.0003%; As Pb and otherimpurities, we used99.99%of zinc plate as an anode, using0.02A current electrolysis to remove the impurities, the time for this process lasted for an hour, this process can effectivelyremove Pb、Fe and other impurities, after the electrolyte, to the zinc electro-deposition,analysis of the resulting zinc cathode, Pb and other impurities content of less than0.0006%.Use the high-purity aluminum cathode and the electrolyte at this pre-treatment,we can receivezinc whose purity is more than99.99%.Based on the NH₄Cl-NaCl-ZnCl₂aqueous solution as the best electro-deposition system,with the reaction time going on, the current efficiency of zinc electrode position reduced, asthis situation, we find a new method that can increase the current efficiency of zinc electrodeposition. The process involves the electrolysis of the expelled residual chlorine and thecontrol of the pH of the electrolyte, the specific conditions are as follows: the uses ofelectrolyte circulation rate of5ml/min to additional the electrolyte which containing14g/LZnO in the based electrolyte to the anode area. At this condition, the pH of the electrolytekeeping at2⁶, the zinc chloride electrolysis cathode current efficiency can reach to95%.Creative ideas in this paper:1、This process can be carried out under normal temprature and normal pressure,it does’tneed a high temperature.2、Through the pre-treatment of the cathode matrix and the electrolyte, we can receive a highpurity zinc. Its purity is higher than99.99%after the deposition, it can be used torecycle,the chlorine which is received on the anode, also can be dried with concentrated sulfuricacid,recycling in the polysilicon industry, this process achieve a target, that zinc andchlorine recycled in a closed loop.3、This process achieves the recycling of zinc, post-processing to solve the problem of zincchloride solution, and the issue of recycled non-ferrous metals.4、We used the elecrolyte circulation during the whole process, it effective control of the pHof the reaction system to improve the current efficiency, to achieve industrial production.