Research On Recovery Process Of Pure Copper From Waste Mobile Phone Circuit Board By Electrodeposition Method

Mobile phones are the most popular electronic devices in the world.There produce a large amount of discarded mobile phone because of the the rapid replacement which waste resources and destroy the environment.Therefore,research on recycling of waste mobile phone circuit boards is a meaningful activity,and through this activity we can not only protect the environment but also recycle resources.Scientists focus on the research of green recycling process of waste mobile phone circuit boards currently.While the electrodeposition method is a low-input,high-output process and the foam flotation process is a highly efficient and selective process,the combination of these two methods to recycling waste mobile phone circuit boards is highly efficient and low pollution.Finally,this study focuses on the efficiently process of recovery of pure copper(purity ?99.5%)from the waste mobile phone circuit boards by electrodeposition.we use the flotation method to enrich copper firstly,and then use the electrodeposition method recover Pure copper from the copper rich group.through this study a green recycling process suitable for electronic waste can be provided.In this thesis,the foamed flotation method was used to pretreat the crushed circuit board particles firstly,and a copper rich group with certain grades was selected for the electrodeposition of pure copper.In this section,the metal-nonmetal separation was investigated,and the metal-nonmetal separation process of flotation-drying-reflotation was established.The experimental results are as follows:The content of metal elements in the-0.074 mm particle size is very small,so that the recovery of the metal elements in the size is very difficult,and the recovery rate are the lowest when using the flotation method;The recovery rate of copper in the 0.074mm-0.125 mm particles are high which have a low proportion of metal elements,while other elements are relatively low,the overall quality of this grade is small and can be recovered by flotation method,to achieve a higher recovery,additional methods are required;The recovery of copper in 0.125 mm-0.15 mm particles and0.15 mm-0.3 mm particles reached more than 90%;The recovery of copper in 0.3mm-0.45 mm particles reached 96.9%,and the recovery of other metal elements was also very high.Secondly,the process of sorting copper from a metal-rich group was examined,and a process for flotation separation of copper from a metal-rich group of-0.074 mm was established by a hydrothermal vulcanization-hot water flotation method.The experimental results are as follows: Hydrothermal vulcanization makesthe metal-rich collective very vulcanized which improves the selectivity of copper and effectively inhibiting other metals,at the same time the 45? water temperature guarantees excellent activity of the flotation agent.Finally,a copper rich group with a copper grade of 92% was obtained by hydrothermal vulcanization-hot water flotation.The key research of this thesis is use electrodeposition process to recover pure copper from the copper-rich groups obtained by flotation.In this section,the electrochemical system used for this experiment was built first,and the H-type electrolytic cell structure separated by a cation exchange membrane was used.The anode and cathode regions were respectively filled with different electrolytes,and an anode bag for electroplating was used to hold the copper-enriched collective powder and titanium anode plate;Secondly,the single factor experience of liquid-solid ratio,temperature,particle size,voltage,p H and material of cathode plate were performed,it is showed that Electrodeposition efficiency is proportional to the ratio of liquid to solid,voltage and temperature,and inversely proportional to p H,the particle size has little effect.At the same time,the process for the electrodeposition of dense copper product is established: voltage is 10 V,the cathode plate is stainless steel plate,p H is0.5,the process for efficient copper recovery process: voltage is 15 V,the cathode plate is pure copper plate with a p H of 0.5.Finally,the effect of flotation enrichment of copper as a deposition material on deposition products was investigated.It is showed that use the copper-rich group obtained by flotation as deposition material can deeply reduce the deposition of other metals at the cathode,thereby increasing the purity of the deposited copper,so that the electrodepositing method recovers pure copper.Through this electrodeposition experiment,pure copper products with a purity of at least 99.67% were finally obtained.To sum up,hydrothermal vulcanization-hot water flotation was used to float the copper-rich collectives first,and then the electrodeposition method was used to recover the pure copper from the copper-rich collectives.Finally,high-purity copper can be recovered from the waste cell phone circuit board.This recycling process has extremely high application value in electronic waste recycling represented by circuit boards while it is highly efficient and environment-friendly.