METHOD AND APPARATUS FOR MANUFACTURING HIGH PURITY ALUMINUM CHLORIDE

摘要

PROBLEM TO BE SOLVED: To provide a method of manufacturing high purity aluminum chloride suitably used as a raw material of aluminum oxide which requires high purity. SOLUTION: A plurality of crystal deposition vessels are used in series. A raw material solution is supplied to a 1st crystal deposition vessel, a solution containing the produced powdery aluminum chloride is overflown to be sent to a 2nd crystal deposition vessel. Slurry taken out from the bottom part of the crystal deposition vessel after the 2nd crystal deposition vessel and before the final stage and containing powdery aluminum chloride is successively sent to the next crystal deposition vessel and the mother liquid of the crystal deposition vessel is successively sent to the previous crystal deposition vessel. Powdery aluminum chloride is recovered from the slurry containing powdery aluminum chloride in the bottom part of the final crystal deposition vessel and the concentration of free hydrochloric acid in the solution in each crystal deposition vessel after 2nd stage is controlled to be higher than that in the solution in the previous crystal deposition vessel. COPYRIGHT: (C)2004,JPO&NCIPI