TH9822A - Xylos production process - Google Patents

Abstract

The de-xylose production process of this invention is as follows: - In the first step, the de-xylose syrup is subjected to enzymatic isomerization in M3 to obtain a mixture of de-xylose and de-xylulose. - In the second step, this mixture is subjected to chromatography in M4 to produce at least two fractions, one with a high de-xylose content (fraction X1) and the other with a high de-xylose content (fraction X2). - In the third step, fraction X2 is reused by passing it through tube P back to M3. The de-xylose is separated from fraction X1, and the remaining fraction is directly hydrogenated.

Claims (8)

1. The process for producing chexolose involves the following steps: - First, a de-xylose syrup is subjected to enzymatic isomerization to create a mixture of de-xylose and de-xylulose. - Second, this mixture is chromatographed to produce at least two fractions: one with a high de-xylose content (fraction X1) and another with a high de-xylose content (fraction X2). - Third, fraction X2 is reused in the isomerization step. The de-xylose is separated from fraction X1, and the remaining fraction is directly hydrogenated. 2. The process described in claim 1 is characterized by the fact that the de-xylulose precursor is prepared by a process consisting of: - Aerobic action of de-glucose syrup using osmophilic microorganisms of the genus Pichia to convert de-glucose to de-arabitol; - Aerobic fermentation of de-arabitol syrup using microorganisms to produce alcohol dehydrogenases of Acetobacter, Gluconobacter, or Klebsiella suitable for the conversion of de-arabitol to de-xylulose; - Isomerization of de-xylulose syrup in the action of glucose isomerase or xylose isomerase to produce a de-xylose-rich syrup. 3. The process described in claim 1 or 2 is characterized by the use of the enzyme glucose-isomerase. 4. Any of the processes described in claims 1-3 that have the characteristic of being carried out in a chromatographic separation step using cationic resin or zeolite. 5. The process described in Reputation 4, where it is a fact that it is carried out in a discontinuous or continuous (variable mobile Beck) chromatographic fractionation step on a suitable highly acidic cationic resin adsorbent, has been pre-ionized with alkaline or alkaline earth ions, or with a cationic zeolite that has been ionized with N1+4+, Na+, K+, and Ca2+ ions. 6. Any one of the processes described in claims 1-5 demonstrates the selection of parameters for the enzymatic isomerization step to result in a syrup with a de-xylose content higher than 53%. 7. Any one of the processes described in claims 1-6 demonstrates the selection of parameters for the chromatographic fractionation process to obtain a product with a high xylose content, expressed as a percentage by weight of dry matter: - from 60-95% - optimal from 75-90% and better from 80-85%, while also containing less than 25% de-xylose and less than 15% optimal. 8. Any of the processes described in claims 1-7 involve the reuse of the starting liquid from xylose crystallization in the chromatographic fractionation step. (Clause 8, 2 pages, 0 images)