A kind of preparation method of straw hemicellulose

A technology for hemicellulose and straw, which is applied to the field of preparation of straw hemicellulose, can solve the problems of increasing the loss and pollution of extraction residues, pollution of residue and alkali wastewater, and high cost of hemicellulose, so as to improve the concentration of target products and reduce purification The effect of burden and alkali consumption saving

Active Publication Date: 2017-01-11
GUANGXI INST OF BOTANY THE CHINESE ACAD OF SCI
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The high amount of alkali not only increases the burden of purification, but also increases the loss and pollution in the extraction residue
In addition, the hemicellulose extracted from the leaching needs to be separated from the lye for recovery. The existing technology generally adopts neutralization-organic solvent precipitation method for separation. Alkaline neutralization and salt formation cannot be recovered, and the volume of organic solvent used is also up to 3% of the leaching solution. Times or even dozens of times more, the dosage is astonishing, the recovery loss is large, and there are hidden dangers of combustion and explosion
Restricted by the above factors, the existing production of hemicellulose extracted by alkaline method has problems such as high cost and pollution of residual alkali wastewater, which greatly affects the promotion and application of hemicellulose products

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
  • A kind of preparation method of straw hemicellulose

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] (1) Extraction: Take a 10L round bottom flask, add bagasse 1Kg to the bottle, connect it to a rotary evaporator, keep the flask at a constant temperature of 80°C in a water bath, draw a vacuum to -0.1Mpa, and inhale 3.5L of 8% (w / v) NaOH solution, continue to rotate for 30 minutes to mix the material and lye and return to normal pressure, continue to rotate and react, and the reaction time is 60 minutes;

[0026] (2) Solid-liquid separation: after the reaction finishes, the material is washed countercurrently 3 times: the first time with deionized water (total 1.2L) washing, finally obtain 3.5L primary washing liquid; the second time with deionized water (total 1.2L) 1.2L) washing to obtain 1.2L of secondary washing solution; washing with deionized water (total 1.2L) for the third time to obtain 1.2L of third-level washing solution; the 3.5L primary washing solution of the above-mentioned gained is used as alkali-containing semi-fiber The element extract enters the next...

Embodiment 2

[0030] (1) Extraction: Take a 10L round bottom flask, add bagasse 1Kg to the bottle, connect it to a rotary evaporator, keep the flask at a constant temperature of 60°C in a water bath, draw a vacuum to -0.1Mpa, and inhale 3.5L of 8% (w / v) NaOH solution, continue to rotate for 40 minutes, return to normal pressure after the material and lye are mixed, continue to rotate and react, and the reaction time is 60 minutes;

[0031] (2) Solid-liquid separation: After the reaction is over, the material is subjected to countercurrent washing for 3 times: for the first time, it is washed with the secondary washing liquid (1.2L in total) of the previous batch of materials (i.e., Example 1), and finally 4.1L of the primary Washing liquid; the second time with the third-level washing liquid (1.2L) of the last batch of materials (i.e. embodiment 1) washing, to obtain the second-level washing liquid 1.22L; for the third time with deionized water 1.2L washing, to obtain three 1.2L of first-gr...

Embodiment 3

[0035] (1) Extraction: Flatten the corn cob with a flattener (thickness is 0.8-5cm), take 1KG and put it into a 10L round-bottomed flask, connect it to a rotary evaporator, keep the temperature of the flask in a water bath at 60°C, and draw a vacuum to -0.05 Mpa, inhale 4L of 8% (w / v) NaOH solution, continue to rotate until the material and lye are mixed and return to normal pressure, continue to rotate and react, the reaction time is 60min;

[0036] (2) Solid-liquid separation: After the reaction is over, the material is subjected to countercurrent washing for 3 times: for the first time, it is washed with the secondary washing liquid (1.22 L) of the previous batch of materials (i.e., Example 2) to finally obtain 4.5 L of primary Washing liquid; the second time washes with the third-level washing liquid (1.2L in total) of the previous batch of materials (i.e. embodiment 2), to obtain the second-level washing liquid 1.2L; washes with deionized water (1.27L in total) for the thi...

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

PropertyMeasurementUnit
molecular weightaaaaaaaaaa
Login to view more

Abstract

The invention discloses a method for preparing straw hemicellulose. The method comprises the following steps: (1) taking straws, crushing, adding the straws into an extraction container, vacuumizing the extraction container so as to press alkaline liquor into the extraction container, maintaining the vacuum degree, uniformly mixing the straws and alkaline liquor, restoring the normal pressure, and extracting the straws, wherein the solid-to-liquid ratio of the straws to alkaline liquor is 1g to (3-4mL); (2) washing the materials after the extraction operation is ended, thereby obtaining alkali-containing hemicellulose extracting solution and residues respectively; and (3) performing ultrafiltration on the obtained alkali-containing hemicellulose extracting solution until the concentration of the hemicellulose in the trapped fluid is more than or equal to 150g / L, collecting the trapped fluid when the conductivity of the trapped fluid is less than or equal to 100mu s / cm, drying, thereby obtaining the hemicellulose product. According to the method disclosed by the invention, high extraction rate can be obtained in short time and under the small solid-to-liquid ratio, the amount of alkali is saved, the target product concentration is improved, and the subsequent purification burden is alleviated.

Description

technical field [0001] The invention relates to a method for preparing hemicellulose, in particular to a method for preparing straw hemicellulose. Background technique [0002] Straw hemicellulose is a polymer with xylose as its main structural unit. It is a polysaccharide second only to cellulose in content, and it accounts for 20-40% of the dry weight of raw materials in grass straw. [0003] Hemicellulose has multiple uses: modified hemicellulose is a new type of industrial material, which is used in degradable plastics, resins, paper industry, solubilizers, emulsifiers, thickeners, lubricants and other fields; hemicellulose Heparin derivatives also have considerable application prospects in the medical industry: sulfate hemicellulose can be used as a substitute for heparin, and has a special role in the prevention and treatment of thromboembolic diseases and respiratory diseases; xylose, Xylitol and furfural are widely used functional sugar alcohols and important platfo...

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 Patents(China)
IPC IPC(8): C08B37/14
Inventor 周玉恒蔡爱华林卫军覃香香
Owner GUANGXI INST OF BOTANY THE CHINESE ACAD OF SCI
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