Method for obtaining xylose hydrolysate by corncob hydrolysis

Abstract

The invention discloses a method for obtaining xylose hydrolysate by corncob hydrolysis, comprising the following steps of: (1) dedusting and crushing corncobs into grains having a grain diameter of 3-5 mm; (2) adding the crushed corncob grains into a 1.5-0.5wt% sulphuric acid aqueous solution or hydrochloric acid aqueous solution, and soaking; (3) heating the solid materials after the soaking is finished to 120-150 DEG C, and performing a gaseous-phase hydrolysis reaction; and (4) after the hydrolysis is finished, washing the materials by a washing liquid to obtain the 12-15wt% xylose hydrolysate. According to the invention, gaseous-phase hydrolysis is adopted, the corncobs are dedusted, crushed and mixed with acid, and then filled in a pot to be directly hydrolysed, and then subjected to affination by adding water to obtain the hydrolysate, and the sugar degree Bx of the hydrolysate is 12-15%, thus greatly increasing the sugar productivity of the corncob hydrolysis; the processes of water washing and acid pre-treatment are omitted during the technical process; the production of the hydrolysis working procedure realizes sewage zero-discharge, and the production cost is reduced simultaneously.

Description

technical field [0001] The invention relates to a xylose preparation process, in particular to a method for obtaining a xylose hydrolyzate by hydrolyzing corn cobs. Background technique [0002] Xylose is an aldopentose. Natural D-xylose exists in plants in the form of polysaccharides, and the content of corncobs is the highest. At present, the production process of xylose mainly uses corncobs as raw materials, and undergoes hydrolysis, neutralization, decolorization, separation, concentration, crystallization, and separation. And other processes, corn cob hydrolysis is the most critical process for preparing xylose, and the quality of the hydrolysis process is directly related to the sugar yield of corn cobs. The traditional corncob hydrolysis process is liquid phase hydrolysis. After the corncob is washed with water and pretreated with acid water, it is hydrolyzed by adding acid and water to heat up, so that the pentosan in the corncob is converted into xylose, and the su...

AI Technical Summary

Problems solved by technology

[0004] From the above analysis, it can be seen that in the methods for preparing xylose from corn cobs reported in the existing literature, pretreatment is required before hydrolysis of xylose to remove impurities on the surface of corn cobs. A large amount of waste acid will be produced

Moreover, the hydrolysis of corn cobs in the above-mentioned documents is all carried out in acid solution, resulting in the final production of a large amount of waste acid solution

It can be seen that when the traditional method is used for the hydrolysis process, the discharge of a large amount of waste acid cannot be avoided.

Using the traditional preparation process, the enterprise needs to invest a lot of funds to purchase hydrochloric acid or process. At the same time, it needs to consume a lot of manpower and material resources in the process of processing a large amount of waste liquid.