阅读说明：本技术 一种高压均质法用于木质素分散液的制备方法 (Preparation method of lignin dispersion liquid by high-pressure homogenization method ) 是由 严辰玥 朱君 罗超 李伟 黄钢 于 2021-09-28 设计创作，主要内容包括：一种高压均质法用于木质素分散液的制备方法,其通过固体分散剂进行一次振动磨加工后,再进行二次液体分散剂高压均质,制备出纳米级分散木质素。该方法包括：(1)将木质素初筛后与固体分散剂一起经振动磨加工后,获得初级分散的木质素；(2)将该初级分散的木质素注入到含有液体分散剂的混合溶剂中,得到的木质素再通过高压均质法进行纳米化均质,制备出纳米级分散木质素。(A high-pressure homogenizing method for preparing lignin dispersion liquid is characterized in that a solid dispersing agent is subjected to primary vibration grinding processing, and then a secondary liquid dispersing agent is subjected to high-pressure homogenizing to prepare nano-grade dispersed lignin. The method comprises the following steps: (1) primarily screening lignin, and then processing the primarily screened lignin and a solid dispersing agent together by a vibration mill to obtain primarily dispersed lignin; (2) injecting the primarily dispersed lignin into a mixed solvent containing a liquid dispersant, and carrying out nano homogenization on the obtained lignin by a high-pressure homogenization method to prepare the nano-scale dispersed lignin.)

1. A method for preparing a lignin dispersion by a high-pressure homogenization method is characterized by comprising the following steps:

primarily screening lignin, and then processing the primarily-dispersed lignin and a solid dispersant by a vibration mill to obtain primarily-dispersed lignin, injecting the primarily-dispersed lignin into a mixed solvent containing a liquid dispersant, and performing nanocrystallization and homogenization on the obtained lignin by a high-pressure homogenization method to prepare nanoscale dispersed lignin;

the vibration grinding lignin processing method comprises the following steps of;

stirring and mixing the lignin and the solid dispersant, putting the mixed sample into a vibration mill, cooling to below zero ℃, wherein the processing time is 5-30 minutes each time, and repeating for 3-5 times.

2. The method of claim 1, wherein the high pressure homogenization is used for preparing the lignin dispersion, and the method comprises the following steps: the solid dispersant comprises: at least one of soluble starch, cyclodextrin and polyethylene glycol.

3. The method of claim 1, wherein the high pressure homogenization is used for preparing the lignin dispersion, and the method comprises the following steps: the preferable proportion of the solid dispersant to the lignin is as follows: and (5-20) mixing the dispersant and the lignin in a ratio of 1.

4. The method of claim 1, wherein the high pressure homogenization is used for preparing the lignin dispersion, and the method comprises the following steps: the liquid dispersant comprises: lignosulfonate dispersants, such AS dispersant AS-3, dispersant Reax-85A; sodium methylenenaphthalenesulfonate dispersants, such as dispersant MF and dispersant NNO. At least one of polyethylene glycol and polyoxyethylene ether as nonionic dispersant.

5. The method of claim 1, wherein the high pressure homogenization is used for preparing the lignin dispersion, and the method comprises the following steps: the mixed solvent is water/ethanol solution, and the volume ratio is 1: 1.

6. The method of claim 1, wherein the high pressure homogenization is used for preparing the lignin dispersion, and the method comprises the following steps: the preferable mixture ratio of the aqueous solution of the liquid dispersant is as follows: the dispersant and the water are 1 to (3-7).

7. The method of claim 1, wherein the high pressure homogenization is used for preparing the lignin dispersion, and the method comprises the following steps: the preferable proportion of the mixed solvent to the lignin is as follows: dispersing agent: lignin 1: (0.2-0.5).

8. The method of claim 1, wherein the high pressure homogenization is used for preparing the lignin dispersion, and the method comprises the following steps: the high-pressure homogenizing method has the homogenizing pressure of 800-1400 Pa. The homogenizing cycle times are 3-9.

Technical Field

The invention relates to the field of homogeneous preparation of lignin dispersion liquid materials, in particular to a preparation method of a lignin dispersion liquid by a high-pressure homogenization method.

Background

With the deep understanding of the problems of environmental pollution and resource limitation by human beings, the renewable utilization of raw materials also becomes a major subject of the modern economic and social development. In plants in nature, the lignin content is only lower than that of cellulose, but is not effectively utilized.

How to effectively decompose lignin is a key problem in recent scientific research. In plants, lignin monomers are polymerized and bonded in various forms, so that the plants are endowed with certain mechanical strength. However, the carbon-carbon polymerization method makes the lignin structure extremely compact and difficult to be destroyed. Not only affecting the separation and extraction of lignin, but also seriously reducing the yield.

There is a need in the art to develop an environmentally friendly and efficient preparation method, i.e. a process for preparing dispersed lignin by a high pressure homogenization method.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a preparation method of a lignin dispersion liquid by a high-pressure homogenization method. Injecting the primarily dispersed lignin into a mixed solvent containing a liquid dispersant, and carrying out nano homogenization on the obtained lignin by a high-pressure homogenization method to prepare the nano-scale dispersed lignin.

In order to achieve the purpose, the technical scheme of the invention prepares the lignin with the nanoscale particle size by a high-pressure homogenization method, thereby obtaining the final lignin raw material with uniform particle size and excellent performance.

The vibration grinding lignin processing method comprises the following steps:

stirring and mixing the lignin and the solid dispersant, putting the mixed sample into a vibration mill, cooling to below zero ℃, wherein the processing time is 5-30 minutes each time, and repeating for 3-5 times.

The solid dispersant comprises: soluble starch, cyclodextrin and polyethylene glycol.

The preferable proportion of the solid dispersant to the lignin is as follows: and (5-20) mixing the dispersant and the lignin in a ratio of 1.

The liquid dispersant comprises: lignosulfonate dispersants, such AS dispersant AS-3, dispersant Reax-85A; sodium methylenenaphthalenesulfonate dispersants, such as dispersant MF and dispersant NNO. Nonionic dispersants polyethylene glycol, polyoxyethylene ether, and the like.

The mixed solvent is water/ethanol solution, and the volume ratio is 1: 1.

The preferable mixture ratio of the aqueous solution of the liquid dispersant is as follows: the dispersant and the water are 1 to (3-7).

The preferable proportion of the mixed solvent to the lignin is as follows: dispersing agent: lignin 1: (0.2 to 0.5)

The high-pressure homogenizing method has the homogenizing pressure of 800-1400 Pa. The homogenizing cycle times are 3-9.

Compared with the prior art, the invention has the following beneficial effects:

the invention has the advantages that:

(1) the invention can greatly enhance the extraction capacity of lignin.

(2) The preparation method is simple, and the performance of the obtained product is obviously higher than that of the product in the existing market.

Detailed Description

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way. It should be noted that variations and modifications can be made by persons skilled in the art without departing from the spirit of the invention. All falling within the scope of the present invention.

Example 1

The vibration grinding lignin processing method comprises the following steps:

1. uniformly stirring and mixing soluble starch and lignin in a volume ratio of 1:5 until the color is uniform to obtain a mixture A;

2. loading the prepared mixture A into a vibration mill, setting the working temperature to be-3 ℃ and the working time to be 5 minutes, starting the vibration mill, and repeating the operation for 5 times after stopping the vibration mill to obtain a mixture B;

3. mixing deionized water and an ethanol solution in a volume ratio of 1:1 to prepare an ethanol solution;

4. mixing the prepared ethanol solution with Reax-85A in a volume ratio of 4:1 to prepare a mixed solvent X;

5. mixing the prepared powder mixture B with a mixed solvent X in a volume ratio of 0.2:1 to prepare a mixture C;

6. feeding the mixture C into a high-pressure homogenizer, setting the pressure amplification to 800 Pa, starting the high-pressure homogenizer, and repeating the operation for 3 times after the high-pressure homogenizer is completely and automatically stopped.

The lignin dispersion D90, which was tested to give a homogeneous product, was 692 nm.

Example 2

The vibration grinding lignin processing method comprises the following steps:

1. uniformly stirring and mixing cyclodextrin and lignin in a volume ratio of 1:10 until the chromaticity is uniform to obtain a mixture A;

2. loading the prepared mixture A into a vibration mill, setting the working temperature to be-3 ℃ and the working time to be 10 minutes, starting the vibration mill, and repeating the operation for 5 times after stopping the vibration mill to obtain a mixture B;

3. mixing deionized water and an ethanol solution in a volume ratio of 1:1 to prepare an ethanol solution;

4. mixing the prepared ethanol solution with AS-3 in a volume ratio of 5:1 to prepare a mixed solvent X;

5. mixing the prepared powder mixture B with a mixed solvent X in a volume ratio of 0.3:1 to prepare a mixture C;

6. feeding the mixture C into a high-pressure homogenizer, setting the pressure increase to 1000 Pa, starting the high-pressure homogenizer, and repeating the operation for 5 times after the high-pressure homogenizer is completely and automatically stopped.

The lignin dispersion D90, which was tested to give a homogeneous product, was 831 nm.

Example 3

The vibration grinding lignin processing method comprises the following steps:

1. uniformly stirring and mixing polyethylene glycol and lignin in a volume ratio of 1:15 until the chromaticity is uniform to obtain a mixture A;

2. loading the prepared mixture A into a vibration mill, setting the working temperature to be-3 ℃ and the working time to be 15 minutes, starting the vibration mill, and repeating the operation for 5 times after stopping the vibration mill to obtain a mixture B;

3. mixing deionized water and an ethanol solution in a volume ratio of 1:1 to prepare an ethanol solution;

4. mixing the prepared ethanol solution with NMO at a volume ratio of 6:1 to prepare a mixed solvent X;

5. mixing the prepared powder mixture B with a mixed solvent X in a volume ratio of 0.4:1 to prepare a mixture C;

6. feeding the mixture C into a high-pressure homogenizer, setting the pressure increase to 1200 Pa, starting the high-pressure homogenizer, and repeating the operation for 7 times after the high-pressure homogenizer is completely and automatically stopped.

The test shows that the lignin dispersion D90 with uniform product is 911 nm.

Example 4

The vibration grinding lignin processing method comprises the following steps:

1. uniformly stirring and mixing polyethylene glycol and lignin in a volume ratio of 1:30 until the chromaticity is uniform to obtain a mixture A;

2. loading the prepared mixture A into a vibration mill, setting the working temperature to be-3 ℃ and the working time to be 30 minutes, starting the vibration mill, and repeating the operation for 5 times after stopping the vibration mill to obtain a mixture B;

3. mixing deionized water and an ethanol solution in a volume ratio of 1:1 to prepare an ethanol solution;

4. mixing the prepared ethanol solution with polyoxyethylene ether at a volume ratio of 7:1 to prepare a mixed solvent X;

5. mixing the prepared powder mixture B with a mixed solvent X in a volume ratio of 0.5:1 to prepare a mixture C;

6. feeding the mixture C into a high-pressure homogenizer, setting the pressure increase to 1400 Pa, starting the high-pressure homogenizer, and repeating the operation for 9 times after the high-pressure homogenizer is completely and automatically stopped.

The lignin dispersion D90, which gave a homogeneous product, was tested to be 659 nm.