Patent ID: 7998710

Claim:
A process for purifying difructose dianhydride III (DFA III) having a purity based on dry weight of at least 70% (w/w), comprising: contacting under aeration (i) a solution containing DFA III having a DFA III purity based on dry weight of at least 60% (w/w) and less than 70% (w/w) and having an R-Bx of 10 or more, with (ii) a yeast that acts on disaccharides or monosaccharides other than DFA III to degrade or incorporate said disaccharides or monosaccharides other than DFA III into the yeast, and with (iii) active carbon particles for a time and under conditions sufficient for impurities to adsorb on the active carbon particles, wherein said active carbon particles are added in amount of 5% (w/w) or less based on the dry weight of the DFA III containing solution, and wherein the activated carbon particles have an average particle size from 15 to 200 microns, thereby providing a contacted solution; separating the contacted solution into a solid phase and a liquid phase; and recovering from the liquid phase DFA III having a purity based on dry weight of at least 70% (w/w), thereby purifying DFA III.