Sucrose - sugarcane

Cane sugar refining includes a decolorization unit to remove melanoidins generated by Maillard reactions, responsible for taste, odor and color which is affecting the quality of the final product. These molecules have some carboxylic groups providing anionic characteristics, well removed from the raw sugar using Strong base anionic (SBA) resins. Activated carbons are also removing colors, but handling and regeneration in a burning kiln is less convenient.

The ion exchange resin are macroreticular resins (with large pore size). Styrenic resin have an excellent color loading capacity, and longer life time, but could be more quickly fouled by organic contaminant with more difficult regeneration. So, Acrylic could be the best choice for raw sugar with high color content, and in any case, it is recommended to clean-up from time to time, the frequency depending of the raw material. The standard layout is composed of two columns in series (The first removing 60% of influent color, the second working as polisher) with a regenerant passing from the polishing column to the working one.

The regeneration will be performed thanks to a brine solution NaCl 10% with small amount of caustic soda (less than 0,5% NaOH) and some solution of brine recovery exists using nanofiltration technology, reducing the cost and the disposal of waste regenerants.