Preparation of Aluminium Iodide
Aluminium Iodide: Eighteen grams of iodine, heated to about 180°C are sublimed over 60 g of aluminum granules (about 10 mesh) heated at 500-625° C in vacuum or a slow stream of nitrogen or carbon dioxide. The almost white product sublimes into the receivers; a large excess of metal is used to ensure complete use of the iodine. Yield about of aluminium iodide is 75% of theory based on the iodine used.
Five grams of pure aluminum are refluxed with 20 g of dry iodine in 80 ml of carbon tetrachloride until the iodine color has completely disappeared. The solvent is distilled off after filtering the reaction mixture to remove any excess metal and washing the residue with 25 ml of carbon disulfide. All operations must be carried out in the absence of moisture. The pale yellow to light brown residue (free iodine) is dried in vacuum at 100 °C; m.p. 191°C; b.p. 382°C. Yield about 90%.
Inorganic laboratory preparations 15, 1962
