Cleaner production method of functional lignin

Abstract

The invention discloses a cleaner production method of functional lignin. On the premise of substantially not changing the natural structure of lignin, the bonds between lignin and cellulose are further opened through high-pressure instantaneous steam explosion, and the dissolution rate of lignin is increased under the condition that the concentration of the extraction liquid is low. The method adopts the circulated extraction process, achieves the repeated use of the acid neutralizer, the alkaline extraction agent and the process water, reduces the material consumption, reduces the pollutant discharge, and achieves low-carbon economy. With the operation of gradient alkaline elution and neutralization, the elution liquid is recycled and the lignin is recovered, so that the acidity of the residue is reduced, which can lay the foundation for ethanol production. The process of the invention has the advantages of low cost, less pollution, high alkali utilization rate and the like, and is recommended to be generalized and applied.

Description

technical field [0001] The invention relates to a process for extracting lignin from industrial fiber lignin residue after hemicellulose is extracted from biomass materials such as corncobs and straws to produce products such as xylooligosaccharides and xylose. Background technique [0002] In the prior art, a large amount of industrial lignocellulosic waste residues are produced after using hemicellulose in biomass to produce xylose and xylooligosaccharides. Most of these waste residues are burned as low-priced fuels, which not only wastes resources but also polluted the environment. After analysis, the main components in the waste residue are water, cellulose, and lignin, and the lignin content is about 45% of the dry matter. Lignin and its derivatives have multiple functions and can be used as dispersants, adsorbents / desorbents, oil recovery aids, and asphalt emulsifiers. The most important contribution of lignin to the sustainable development of human beings is to prov...

AI Technical Summary

Problems solved by technology

[0003] Traditional technology (publication number: CN1763208) has made great efforts for the utilization of biomass lignin, and it adopts the inorganic matter extraction method to extract the lignin in the waste residue, and the alkalinity needs to be adjusted to 1%~35% when pulping, with Soluble lignin in alkaline aqueous solution. During the neutralization process, it is necessary to adjust the pH to 2~3 with acid to precipitate lignin from the filtrate. The alkali added before is neutralized and cannot be fully utilized and recycled. cause serious waste