Process for improving sucralose purity and yield

A method of purifying sucralose from a crude sucralose solution comprising the steps of:

• (a) performing a crystallization procedure on said crude sucralose solution to obtain crystalline sucralose and a first mother liquor;
• (b) dissolving said crystalline sucralose to obtain a sucralose solution and performing a crystallization procedure on the sucralose solution to obtain a more pure crystalline sucralose and an additional mother liquor;
• (c) performing step (b) at least two additional times;
• and
• (d) recycling said mother liquor obtained from one or more of said crystallization procedures into one or more of said sucralose solutions utilized in the earlier crystallization procedures.

A method of purifying sucralose from a crude sucralose solution comprising the steps of:

• (a) subjecting a feedstock comprising said crude sucralose solution to a non-crystallization purification step to yield an increased purity sucralose solution;
• (b) performing a crystallization procedure on said increased purity sucralose solution to obtain crystalline sucralose and a first mother liquor;
• (c) dissolving said crystalline sucralose to obtain a sucralose solution and performing a crystallization procedure on the sucralose solution to obtain a more pure crystalline sucralose and a second mother liquor;
• and
• (d) repeating step (c) at least two additional times to obtain a further purified sucralose and at least one additional mother liquor.

A method of obtaining sucralose from a feed mixture comprising 6-O-acyl-4,1′,6′-trichloro-4,1′,6′-trideoxygalactosucrose, other chlorinated sucrose byproducts, and optionally blocked or partially blocked chlorinated sucrose byproducts comprising the steps of:

• (a) performing a non-crystallization extraction step on said feed mixture to obtain an increased purity 6-O-acyl-4,1′,6′-trichloro-4,1′,6′-trideoxygalactosucrose composition;
• (b) performing a crystallization procedure on said increased purity 6-O-acyl-4,1′,6′-trichloro-4,1′,6′-trideoxygalactosucrose composition to obtain 6-O-acyl-4,1′,6′-trichloro-4,1′,6′-trideoxygalactosucrose and a mother liquor;
• (c) performing at least three additional sequential crystallizations of the 6-O-acyl-4,1′,6′-trichloro-4,1′,6′-trideoxygalactosucrose to obtain a substantially pure 6-O-acyl-4,1′,6′-trichloro-4,1′,6′-trideoxygalactosucrose and additional mother liquor;
• and
• (d) converting said substantially pure 6-O-acyl-4,1′,6′-trichloro-4,1′,6′-trideoxygalactosucrose to substantially pure sucralose.

A method of obtaining sucralose from a feed mixture comprising 6-O-acyl-4,1′,6′-trichloro-4,1′,6′-trideoxygalactosucrose, other chlorinated sucrose byproducts, and optionally other blocked or partially blocked chlorinated sucrose byproducts comprising the steps of:

• (a) performing a non-crystallization extraction step on said feed mixture to obtain an increased purity sucralose precursor stream;
• (b) converting said 6-O-acyl-4,1′,6′-trichloro-4,1′,6′-trideoxygalactosucrose in said increased purity sucralose precursor stream to sucralose;
• (c) crystallizing said sucralose to obtain a crystalline sucralose and a mother liquor;
• and
• (d) performing at least three additional sequential crystallizations of said crystalline sucralose to obtain a substantially pure sucralose and additional mother liquor.

A method for purifying sucralose from a crude sucralose solution comprising the steps of:

• (a) subjecting a feedstock comprising said crude sucralose solution to a non-crystallization purification step to yield an increased purity sucralose solution;
• (b) performing a crystallization procedure on said increased purity sucralose solution to obtain crystalline sucralose and a mother liquor;
• (c) recycling at least a portion of said mother liquor to said feedstock utilized in step (a);
• and
• (d) performing at least three more sequential crystallization procedures on said crystalline sucralose to yield a final crystalline sucralose composition wherein the level of other chlorinated sugars is less than 0.2% of the composition by weight.