PRODUCTION OF ERYTHRITOL CRYSTAL OF HIGH PURITY

摘要

PROBLEM TO BE SOLVED: To provide a production process for erythritol of much more increased purity and crystal forms than those of the conventional product. SOLUTION: On the step of crystallization of erythritol from its aqueous solution, the concentration of erythritol in the aqueous solution is adjusted to 30-60 wt.% at the start of the crystallization and the solution is cooled down <=20 deg.C/hour, seed crystals are added on the way of the cooling crystallization, and the solution is cooled down to the temperature lower than 20 deg.C. In this case, the seed crystals of erythritol are added to the crystallization tank at the step where the temperature in the crystallization tank is lower than the temperature corresponding to the saturated solubility and the difference is smaller than 15 deg.C. The amount of seed crystals of erythritol is 0.1 wt.% or less based on the erythritol to be precipitated in the crystallization tank.