Hydrolyzing method of cellulose and hemicellulose in waste plant

Abstract

A hydrolyzing method of cellulose and hemicellulose in waste plant, comprises the following steps: adding hydrochloric acid in 15-20wt% concentration into finely divided waste plant in a sufficient amount to flood the waste plant, heating the mixture by microwave for 1-2h at the temperature of 100-110 DEG C, putting the waste plant and hydrochloric acid processed by microwave into a high pressurereaction vessel to maintain for 1-2h at the air pressure of 1.2-1.35MPa and the temperature of 120-140 DEG C to hydrolyze, then filtering the prepared substance, separating hydrolysate and residue toobtain a hydrolysate. The obtained hydrolysate is subject to hydrochloric acid recycling to separate hydrochloric acid and monosaccharide liquid, the monosaccharide liquid can be further used for theproduction of fuel ethanol. The hydrolyzing method has the advantages of low cost, simple technology, convenient for the recovery of hydrochloric acid, and preventing the deterioration of working environment.

Description

technical field [0001] The invention relates to the field of renewable resources—the utilization of waste plants, in particular to a method for hydrolyzing various waste plants containing cellulose and hemicellulose into glucose and xylose. Background technique [0002] At present, many departments in our country are developing and utilizing renewable resources—especially waste plants—to produce fuel ethanol, and some large enterprises are conducting trial production, but the problem in the existing technology is the cellulose and hemifibers in waste plants The cost of the process of turning cellulose into glucose and xylose is too high, which affects the production cost of the entire fuel ethanol, so that it cannot be put into mass production. [0003] Most of the methods of prior art experiments and trial production use dilute sulfuric acid to hydrolyze hemicellulose to obtain xylose, and then add cellulase to the residue containing cellulose and lignin to hydrolyze cellul...

AI Technical Summary

Problems solved by technology

[0002] At present, many departments in our country are developing and utilizing renewable resources—especially waste plants—to produce fuel ethanol, and some large enterprises are conducting trial production, but the problem in the existing technology is the cellulose and hemifibers in waste plants The process cost of converting ketones into glucose and xylose is too high, which affects the production cost of the entire fuel ethanol, so that it cannot be put into mass production

[0003] Most of the methods of prior art experiments and trial production use dilute sulfuric acid to hydrolyze hemicellulose to obtain xylose, and then add cellulase to the residue containing cellulose and lignin to hydrolyze cellulose (also known as enzymatic process) , but under the current conditions, the enzymatic process requires very harsh process conditions, and expensive cellulase preparations must be purchased, so the production cost is very high

[0004] Another method of hydrolyzing cellulose, which is also the most classic method, is to hydrolyze cellulose and hemicellulose with concentrated sulfuric acid. This method is simple and technically reliable. However, due to the similar molecular weights of glucose and sulfuric acid, it is impossible to recover sulfuric acid with a diffusion dialyzer. , instead of producing polysaccharides first and then separating them, the production efficiency of this method is very low, so it cannot be used in production

[0005] Recently, a dilute acid high-temperature hydrolysis method has been developed, but it is found that the converted glucose decomposes in large quantities at high temperature, so the conversion rate is not high