High-yield preparation method for high-purity low-molecular-weight lignin

A low molecular weight, lignin technology, applied in the field of biochemical industry, can solve the problems of serious environmental pollution, low yield and high molecular weight of lignin

Active Publication Date: 2015-12-30
BEIJING UNIV OF CHEM TECH
View PDF7 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The molecular weight of raw lignin in nature is as high as hundreds of thousands. The molecular weight of lignin obtained by different preparation methods is generally several thousand to tens of thousands, and the yield is low and the preparation conditions are harsh.
The traditional process uses the alkaline method to prepare lignin. This method uses a large amount of high-concentration alkaline solution, which causes serious environmental pollution and difficult water treatment in the later stage. The lignin prepared by this method is usually mixed with impurities such as cellulose and hemicellulose. The yield Usually less than 20%, lignin molecular weight is higher (usually Mw greater than 10000)

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • High-yield preparation method for high-purity low-molecular-weight lignin
  • High-yield preparation method for high-purity low-molecular-weight lignin
  • High-yield preparation method for high-purity low-molecular-weight lignin

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0023] High-purity low-molecular-weight lignin is prepared with high yields from corn cobs. The specific method is: take 200 g of corn cobs that are crushed to a diameter of about 2 cm, soak them in 0.5% (w / w) dilute sulfuric acid solution and place them at room temperature for 8 hours, and filter them by suction. Separation of solid and liquid. Pour the pre-impregnated corncobs into the screw pressure continuous steam explosion extruder, feed the steam pressure to 1.5MPa, and the corncobs stay in the retainer for 5min, release the pressure to a standard atmospheric pressure to obtain steam explosion materials, wash with water drying. Get 5g of dry steam-explosion material and join 50ml, 80% (v / v) ethanol aqueous solution with solid-to-liquid ratio 1 / 10 (w / w), heat up to 160 ℃ in autoclave, set stirring speed 500rpm, React for 2 hours. After cooling to room temperature, the extract was separated by filtration, and an appropriate amount of 0.5% (w / w) dilute sulfuric acid solu...

Embodiment 2

[0025] Using cassava distiller's residue as raw material to prepare high-purity low-molecular-weight lignin with high yield, the specific method is: take 200g of cassava distiller's residue, wash the raw material with water to remove dust, impurities and sugar, immerse in 0.2% (w / w) hydrochloric acid solution and place it at room temperature for 10 hours , and the solid-liquid was separated by suction filtration. Pour the pre-soaked cassava distiller's residue into a screw-pressurized continuous steam explosion extruder. The steam pressure is 1.2MPa. The cassava distiller's residue stays in the retainer for 8 minutes, and the pressure is released to a standard atmospheric pressure to obtain the steam explosion material. , wash and tumble dry. Take 5g of dry steam explosion material and add it to 75ml, 96% (v / v) 1,4-dioxane aqueous solution at a solid-to-liquid ratio of 1 / 15 (w / w), and heat up to 200 in the autoclave °C, set the stirring speed at 500 rpm, and react for 2 hours...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a high-yield preparation method for high-purity low-molecular-weight lignin and belongs to the field of biochemical engineering. According to the method, non-grain crops or bioethanol wood fiber waste is adopted as raw materials, the raw materials are pretreated through dilute acid steam explosion, and steam explosion materials with hemicellulose removed are obtained; the steam explosion materials and an ethanol water solution are added to a high-pressure reactor, temperature rises to 100 DEG C to 300 DEG C, and reacting is carried out for 0.5 h to 5 h at the temperature; after reacting is finished, cooling is carried out, products are dissolved in a reaction solution, pH is adjusted to be 1-7, and the high-purity low-molecular-weight lignin is obtained. The method has the advantages of being economical and feasible, environmentally friendly and high in yield and efficiency, and has wide prospects in the high-valued utilization direction of the lignin in agricultural waste.

Description

technical field [0001] The invention belongs to the field of biochemical industry, and relates to a method for preparing high-purity low-molecular-weight lignin with high yield by utilizing non-grain crops or bioethanol lignocellulosic waste. Background technique [0002] Lignin is the second most abundant renewable biopolymer in nature, and it is also the only renewable aromatic biopolymer in nature. Lignin molecules are based on p-hydroxyphenylpropane, guaiacylphenylpropane, syringylphenylpropane and their structural derivatives, and become an aromatic polymer with a three-dimensional space network structure through C-O bonds and C-C links . Lignin has not been efficiently utilized so far, and a large amount of lignin resources are usually used for combustion for heating. [0003] High-purity low-molecular-weight lignin can be used to replace petroleum-based aromatic compounds and to prepare bio-based renewable functional polymer materials. The molecular weight of raw l...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C07G1/00
Inventor 王文雅欧阳显鸿袁其朋张秋翔李双喜
Owner BEIJING UNIV OF CHEM TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap