Recovery of valuable materials from spent nickel-cadmium battery
Shun-Myung Shin, Sung-Ho Joo, Gong-Joo Shin, Jung-Yeul Yun and Jei-Pilwang
This study was focused on recycling process newly proposed to recover electrodic powder from spent nickel-cadmium battery using thermal treatment process and selectively separate cadmium by means of distillation method. This new process was designed to prevent explosion of batteries during thermal treatment under inert atmosphere. Spent nickel-cadmium batteries were heated over range of 300°C to 600°C for 2 hours and each component was completely separated inside reactor after experiment. Electrodic powder was successfully recovered from bulk components containing several pieces of metals through sieving operation. The electrodic powder obtained was examined by X-ray diffraction (XRD) and atomic absorption spectroscopy (AA) and image of the powder was taken by scanning electron microscopy (SEM). It was finally found that nickel and cadmium were mainly recovered to about 30 wt.% and 40 wt.% in electrodic powder, respectively. In addition, the XRD result showed that the condensed product was characterized as metallic cadmium.
Keywords: Nickel-cadmium battery, Electrodic powder, Thermal treatment, Distillation