Study On The Recovery Of ABS Plastic、Copper And Nickel From Waste Electro-plates

With the significant increase in the sales of cars and electronic products in our country, the discarded quantity growes steadily. Large quantity of ABS plastic electro-plates are included in these waste products. Contrary to common plastics, these electro-plates contain large amount of metals which are severe pollution to the environment. Therefore, it is of great significance to and make some innocent treatment and recover these electro-plates. For the problems existing in the present recovery process, such as environment pollution and low recovery rate, the present work is put forwarded to recover Cu and Ni simultaneously, without bring any damage to ABS plastic bases or secondary pollution.Firstly, the stripping process of ABS plastic electro-plates was carried out, with hydrochloric acid and hydrogen peroxide as the stripping solution. The influences of the mass fraction of hydrochloric acid and hydrogen peroxide, solution-solid ratio (R) and reaction time on stripping rate was investigated. The optimum process condition was obtained after the optimization by orthogonal test:HCl12wt%, H2O23wt%, R8and stripping time30min. The stripping rate is high up to99%under the optimum process conditon.After the filtration by active carbon, the stripping solution was placed under volts D.C. to recover copper by electrolytic process. Different electrode materials were applied for the experiment in the initial stage. Copper and iridium titanium dioxide were determined as the cathode and anode material. Then the effect of voltage, electrode spacing, anode area and electrolytic time was investigated separately and the process was optimized by orthogonal test. The optimum electrolytic process was obtained:voltage2.0V, electrode spacing1.0cm, anode area10.5cm2and electrolytic time30min.Finally, nickel chloride hexahydrate was obtained after evaporation concentration and cooling crystallization from the electrolytic treated solution. And the residual solution after the recovery of nickel chloride hexahydrate was recycled for the stripping solution. The effect of the mass fraction of hydrochloric acid and hydrogen peroxide, adn solution-solid ratio (R) in the recycled solution on stripping rate was investigated, and the process was optimized by orthogonal test. A new optimum process condition was obtained in the preparation of electrolytic solution from recycled solution:HC110wt%, H2O24wt%and R8. Compared with fresh electrolytic solution, the amount of hydrochloric acid was decreased to2wt%and the amount of hydrogen peroxide was increased to1%in the recycled solution.