Determination of recovered Cadmium and Nickel from spent alkaline batteries using acidic solutions and AAS measurements

Abstract

This research include the recovery study of cadmium and nickel from spent alkaline batteries was conducted by two different acidic solutions. The first one is nitric acid, which was used for cadmium recovery; the other is sulfuric acid, which was used for nickel recovery. Many factors affected the recovery process were studied, such as concentration, volume, time, weight and temperature. The parameters which effect on the precipitation of metal ion from leaching solution were also studied, such as pH, time, concentration and temperature. The recovery percentages of metal ion were found to be 98.5% of cadmium using optimum conditions (5 M HNO3, 2 gm sample, 2 hr, and 20 ml acid volume) and 99% for nickel using (5 M H2SO4, 2 gm sample, 2 hr, and 20 ml acid volume). The precipitation processes were carried out using (2 M NaOH) solution. The precipitation percentages were found to be 98.6% and 99.1% of cadmium and nickel respectively. The purification processes were conducted using double distilled water. The purity of products Cd (OH)2 and Ni (OH)2 was found to be 98.08% and 98.23% respectively. The concentration of metal ion in the solutions was measured using AAS; the method was linear with R2 of (0.9995 and 0.9993) for Ni and Cd respectively.