Patent ID: 6150364
Filing Date: 2000-11-21
Classification: C07D

Abstract:
A process for the purification and crystallization of riboflavin comprising the steps of:(a) dissolving needle-shaped riboflavin of a stable modification A form in an aqueous mineral acid solution at a temperature not exceeding about 30.degree. C. with intermixing;(b) adding active charcoal to the solution to adsorb dissolved impurities from the solution onto the active charcoal;(c) filtering the solution containing the active charcoal by counter-current filtration over a ceramic membrane having a pore size of about 20 to about 200 nm to form a filtrate;(d) combining a five- to ten-fold amount of water (vol./vol.) at a temperature not exceeding about 30.degree. C. with the filtrate in a crystallizer to form precipitated spherical crystals of riboflavin; and(e) separating the precipitated spherical crystals of riboflavin by centrifugation or filtration.