Aluminium chloride production. Apparatus for the synthesis of aluminium chloride (AlCl3) in the laboratory. Chlorine (Cl2) gas is produced by the action of hydrochloric acid (HCl) on an unidentified liquid (left). The gas is drawn over heated pieces of aluminium (Al) metal (centre) to produce aluminum chloride in the receptacle at right. Aluminium chloride is used as a catalyst in industry.