Metal Recovery from Chromium Electroplating Sludge by Thermite Reaction with Aluminum Dross

The purpose of this research is to recover a metallic resource in wastes by using the thermite reaction that takes place between an oxides and metallic aluminum. We tried to cause the thermite reaction between the chromium oxide in the chromium electroplating sludge and the metallic aluminum in the Al dross, and to recover metallic chromium. After the sample was prepared under various conditions, reaction heat, starting temperature and reaction ratio were analyzed by differential thermal analysis and ICP-AES. As a result, the thermite reaction was caused between the sludge and Al dross, and Cr2O3 in the sludge was reduced to metallic Cr. Moreover, along with the processing time by a ball mill, reaction heat and reaction ratio increased, and starting temperature decreased.