Recrystallize in enough methanol to dissolve, then place in refrigerator for large crystals (4 days) OR freezer for smaller (4-8 hours). do multiple smaller pulls. 90ml acetone 10ml chloroform 1-2gm NaOH Yield~ 4gm Please note this is not safe for consumption. It may contain small amounts of un reacted chemicals or many possible side products.