Method for preparing plant hemicellulose hydrolysis liquid and method for extracting xylose and gum sugar

Abstract

The invention provides a method for preparing plant hemicellulose hydrolysis liquid and a method for extracting xylose or gum sugar. The method for preparing the hemicellulose hydrolysis liquid comprises the steps of soaking, acid liquid pretreatment, heating hydrolysis, washing and the like. The problems of low sugar liquid concentration and large acid liquid reclaiming amount caused by a large liquid ratio when flowing water is boiled are solved by adopting a flowing water-free wet material boiling method; and on the other hand, reduction of sugar liquid concentration and dilution of acid liquid caused by changing water vapor into condensed water during directly heating the water vapor and preserving the heat are also avoided by adopting an indirect heating mode in a heat preservation boiling process so as to obtain high-concentration sugar liquid and reduce the concentration of the acid liquid used at initial soaking.

Description

technical field [0001] The invention belongs to the field of chemical industry, and in particular relates to a method for preparing hemicellulose hydrolyzate and extracting xylose and arabinose. Background technique [0002] Xylose and arabinose are versatile five-carbon sugars that are mainly present in the form of polymers in plant hemicellulose. The dry matter of higher plants generally contains about 20-35% hemicellulose. Therefore, xylose and arabinose can be produced by hydrolyzing hemicellulose in higher plants. Among them, arabinose is also contained in a large amount in some plant gums, such as arabic gum, but its extraction method is also hydrolyzed into a hydrolyzate and then purified, and the method is similar to the preparation of arabinose by hydrolyzing hemicellulose. [0003] The methods of hydrolyzing plant hemicellulose mainly include enzymatic method and acid hydrolysis method. Although the enzymatic method has mild conditions, it has not been industrial...

AI Technical Summary

Problems solved by technology

The disadvantage of this patented method is that ① since the solid-liquid ratio is only 1:0.25-1.25, it is difficult to make the materials fully contact with the acid solution by spraying, and those materials that cannot contact the acid solution will not be hydrolyzed, thereby reducing the yield of sugar; ②Due to direct heating with steam, the material in contact with steam will absorb condensed water and reduce the concentration of sulfuric acid, resulting in uneven hydrolysis and incomplete hydrolysis, which will also reduce the yield of sugar; ③Due to the introduction of steam Direct heating reduces the concentration of sulfuric acid, so the initial concentration of sulfuric acid is required to be high, and the recovered sulfuric acid needs to be concentrated before it can be recycled, thus increasing the cost

The disadvantage of this patented method is that it is still necessary to use tedious column chromatography to separate various monosaccharides in the crude product of mixed monosaccharides, which is difficult for industrialization