CPC C07H 1/06 (2013.01) [C07H 3/02 (2013.01); C07B 2200/13 (2013.01)] | 7 Claims |
1. A preparation method of crystalline D-psicose, wherein, successively performing evaporative crystallization, crystal regulation, and cooling crystallization to obtain crystalline D-psicose;
said evaporative crystallization comprises adding crystal seeds when a solid mass content is 70˜75% to perform an evaporative crystallization;
said cooling crystallization is performed by applying a stepped cooling having a slow cooling rate in an initial stage and a rapid cooling rate in a later stage; wherein said stepped cooling has following operations: in a range of 50˜41° C., cooling at a rate of 0.1˜0.3° C. per hour; in a range of 41˜35° C., cooling at a rate of 0.4˜0.6° C. per hour; in a range of 35˜30° C., cooling at a rate of 0.9˜1.1° C. per hour; and the crystallization is finished when temperature is cooled to 30° C.; and said crystal regulation is carried out by adding water at the same time as an evaporative crystallization is performed, and a solid mass content is maintained constant during the crystal regulation process.
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