For each experiment, 100 g of dross sample was used. The appropriate volume of sulfuric acid, equivalent amount of concentrated H2SO4, was used to keep the dross/acid ratio as 5:8. This amount of acid was used in different diluted forms (such as 5, 10 and 15 wt.%). The same reactor, Fig. 4, was used for extraction experiments. The solid purified residue obtained after leaching impurities was used as the starting material for extraction of aluminum. Extraction was carried out using solutions of H2SO4 (35%, 45%, and concentrated 98% by weight). One hundred grams of sample was used in each experiment with the stoichiometric amount of H2SO4 calculated from Eq. (1): equation(1)