Louisiana State University and Agricultural & Mechanical College

Societe Nouvelle De Recherches Et D'applications Industrielles

Michael Saska

Feng Chen

Xaivier Lancrenon

Moustapha Diack

Improved separations of xylose, mannose, galactose, arabinose, glucose, xylitol, arabitol; sorbitol, galactitol, or mannitol (and other monosaccharides and sugar alcohols) from other sugars and sugar alcohols may be achieved by chromatography over hydroxyl-form anion exchange surfaces prepared from anion exchange resins at relatively low hydroxyl concentrations. When a strong base anion exchange resin, such as a chloride-form strong base anion exchange resin, is conditioned with a low concentration of hydroxyl (for example, an NaOH solution with a concentration between 0.1 and 1000 mM, most preferably between 1 and 10 mM), the conditioned resin separates a number of sugars and sugar alcohols from one another, while still allowing ready desorption from the resin.

Process for the separation of sugars

Nanofiltration is used to decolorize sugar juice or syrup. The resulting permeate may be used directly to crystallize white sugar without an intermediate step of producing a raw sugar, even though the color of the permeate is substantially higher than the highest color that is acceptable in a conventionally decolorized syrup used to crystallize white sugar. Significant cost savings are thus achieved in producing white sugar.

Method for producing white sugar

Nanofiltration is used to decolorize sugar juice or syrup. The resulting permeate may be used directly to crystallize white sugar without an intermediate step of producing a raw sugar; even though the color of the permeate is substantially higher than the highest color that is acceptable in a conventionally decolorized syrup used to crystallize white sugar. Significant cost savings are thus achieved in producing white sugar.

When a strong base anion exchange resin, such as a chloride-form strong base anion exchange resin, is conditioned with a low concentration of hydroxyl (for example, an NaOH solution with a concentration between 1 and 10 mM), the conditioned resin separates in, sit, Is from sugars and sugar alcohols, while still allowing ready desorption of the sugars from the resin. The feedstock is first passed over a column containing this conditioned resin, followed by a mobile phase solvent, preferably water. The inositols have a lower affinity for the treated resin than do the sugars and sugar alcohols in the feedstock, and therefore pass through the column more quickly. The process may economically be performed on industrial-scale inositol separations, particularly when used in a preferred simulated moving bed chromatographic system.

Separation of inositols from sugars and sugar alcohols

The invention relates to a process for softening an aqueous sugar juice containing sugars and Ca.sup.2+ and/or Mg.sup.2+ ions, such as a sugar factory molasses by means of a cation exchange resin, in the form of Na.sup.+ and/or K.sup.+, and for regeneration of said resin, comprising: (a) a softening step wherein the said sugar juice is brought into contact with the said cation exchange resin, in the form Na.sup.+ and/or K.sup.+, to give, on the one hand, a softened sugar juice depleted in Ca.sup.2+ and/or Mg.sup.2+ ions and charged with Na.sup.+ and/or K.sup.+ ions and, on the other hand, a cation exchange resin charged with Ca.sup.2+ and/or Mg.sup.2+ ions, and (b) a step for the regeneration of said latter resin, characterised in that the regeneration step (b) comprises bringing the said resin into contact with a liquid effluent produced on separation by chromatography of the sugars from a softened aqueous sugar juice containing sugars and Na.sup.+ and/or K.sup.+ ions, said liquid effluent containing the majority of the Na.sup.+ and/or K.sup.+ ions initially present in the softened sugar juice.

Process for softening a sugar-containing aquesous solution, such as

This invention relates to a process for the purification of crude terephtic acid. The process includes heating the crude acid on a first plate and locating a second plate adjacent the first plate whereby vapors emanating from the crude acid form a sublimate on the second plate. The principal impurity removed is 4-carboxybenzaldehyde. The crude acid produced is applied to the first plate as a layer having a thickness of about 2 to about 5 mms thick and heated to a temperature of from about 180.degree. to about 220.degree. C. The upper plate is not heated except by the convective heat transfer and the heat of sublimation provided by the vapor moving from the crude acid layer to the second plate.

Growing community of inventors

Baton Rouge, LA, United States of America

Michael Saska