| 摘要 |
1,163,196. Separation of sugars. LAEVOSAN - GESELLSCHAFT CHEM. PHARM. INDUSTRIE FRANCK & DR. FREUDL. 2 March, 1967 [30 March, 1966], No. 9872/67. Heading C2C. Mixtures of sugars are separated by contacting an aqueous or aqueous/alcoholic solution of the mixture with a cation exchange resin which is charged with hydrazine, to form the corresponding sugar hydrazones and recovering the component sugars by fractional hydrolysis of the hydrazones. It is preferred to use a cation exchange resin which is also charged with hydrogen ions, e.g. equimolar amounts of hydrogen ions and hydrazine ions. The temperature at which contact and hydrolysis are effected depends on the particular sugars, each of which form hydrazones of varying hydrolytic stability, e.g. fractional hydrolysis of invert sugar hydrazones is carried out at 40-80‹ C. to separate glucose and fructose. The process is conveniently effected on a column of cation exchange resin, fractional hydrolysis being effected by elution with water. The eluate fractions contain either the pure sugar component or are enriched in the required component which can be isolated by crystallization. Examples describe the separation of glucose and fructose from invert sugar, fructose and galactose from mixture thereof, sorbitol and glucose from a mixture thereof and pure lactulose from a mixture of lactulose, galactose and lactose. |
