Purification Methods
-D-Galactose is crystallised twice from aqueous 80% EtOH at -10o, then dried in a vacuum oven at 90o over P2O5 for 10hours. [Link Biochemical Preparations 3 75 1953, Hansen et al. Biochemical Preparations 4 2 1955.] Also purify it by recrystallising the dried solid (150g) in hot H2O (150mL), then adding hot MeOH (250mL) and hot EtOH (500mL), stirring to mix, filtering through a bed of charcoal, and the clear filtrate is stirred to initiate crystallisation. After standing overnight at 10o, the crystals of the -anomer are filtered off by suction, washed with MeOH, then EtOH, and dried (yield 130g), and more can be obtained by evaporation of the filtrate and washing as before. [Wolfrom & Thompson Methods in Carbohydrate Chemistry I 120 1962, Academic Press, Beilstein 1 IV 4336.]
