Abstract:
PROBLEM TO BE SOLVED: To provide a method of and a device for efficiently purifying to reduce the remaining impurities in a product. SOLUTION: There are provided the method of and the device for purifying the mixture of substances using optionally fractional crystallization. Impurities often precipitate in addition to a desired product during the crystallization process since these impurities are present at high concentrations surpassing the solubility limit. According to the inventive method, a solvent or a mixture of solvents with a strong affinity to an impurity with a tendency to precipitate is added to the mixture of substances or its melt to be purified so that the corresponding impurity is retained in solution. If there are several impurities with a tendency to precipitate, some of the impurities can be retained in solution by adding a suitable solvent, and the remainder can be separated by mechanical means, for example, filtration by suction, centrifugation and the like. COPYRIGHT: (C)2010,JPO&INPIT