CN111320704A - Preparation method of low-whiteness cellulose ether - Google Patents
Preparation method of low-whiteness cellulose ether Download PDFInfo
- Publication number
- CN111320704A CN111320704A CN202010338465.3A CN202010338465A CN111320704A CN 111320704 A CN111320704 A CN 111320704A CN 202010338465 A CN202010338465 A CN 202010338465A CN 111320704 A CN111320704 A CN 111320704A
- Authority
- CN
- China
- Prior art keywords
- cooking
- cellulose ether
- fiber
- solid
- alkali liquor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08B—POLYSACCHARIDES; DERIVATIVES THEREOF
- C08B11/00—Preparation of cellulose ethers
- C08B11/02—Alkyl or cycloalkyl ethers
- C08B11/04—Alkyl or cycloalkyl ethers with substituted hydrocarbon radicals
- C08B11/08—Alkyl or cycloalkyl ethers with substituted hydrocarbon radicals with hydroxylated hydrocarbon radicals; Esters, ethers, or acetals thereof
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08B—POLYSACCHARIDES; DERIVATIVES THEREOF
- C08B11/00—Preparation of cellulose ethers
- C08B11/20—Post-etherification treatments of chemical or physical type, e.g. mixed etherification in two steps, including purification
- C08B11/22—Isolation
Landscapes
- Chemical & Material Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Biochemistry (AREA)
- Materials Engineering (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Polysaccharides And Polysaccharide Derivatives (AREA)
Abstract
A preparation method of low-whiteness cellulose ether belongs to the technical field of fiber processing. The preparation method is characterized by comprising the following preparation steps in sequence: crushing: crushing the fiber material to a particle size of 50-150 meshes; and (3) cooking: soaking the fiber micro powder obtained in the step 2) into an alkali liquor with the mass concentration of 1.5-15%, and cooking for 30-90 minutes at the cooking temperature of 150-260 ℃; and etherifying and rinsing to obtain the product. The main improvement of the invention lies in that the whole cellulose ether step sequence is adjusted, and in the production method, the steps of stewing, etherification and rinsing adopt the prior process conditions and material ratio of the cellulose ether to obtain ideal preparation effect.
Description
Technical Field
A preparation method of low-whiteness cellulose ether belongs to the technical field of fiber processing.
Background
Cellulose ether is a high molecular compound which can be dissolved in water, dilute alkali solution and organic solvent, has thermoplasticity and excellent performance, and is widely used in the industries of buildings, cement, petroleum, food, textile, detergent, coating, medicine, paper making, electronic components and the like. The basic steps of a conventional cellulose ether preparation process are: cooking, bleaching, crushing, etherification and rinsing. Wherein the cooking process is to heat the fiber in alkali liquor to over 100 ℃ for reaction; the fiber material after cooking and bleaching is subjected to a crushing process. Wherein the boiled fiber needs to be subjected to multiple operations of temperature rise, rinsing, temperature reduction, liquid removal and the like to avoid the influence of alkali liquor on the bleaching process. The bleached fiber material can avoid the bleaching agent from corroding the crusher, and the operations of heating, rinsing, cooling, removing liquid and the like can be carried out for many times, so that the etherification reaction can be carried out after the crushing.
The inventor of the invention considers that the operations of steaming, bleaching, rinsing, liquid removal and the like which are continuously repeated in the traditional preparation process of the cellulose ether greatly prolong the production process and ensure that the preparation efficiency of the cellulose ether cannot be greatly improved. Moreover, a large amount of alkali-containing sewage and salt-containing sewage are generated in the process; resulting in large dosage of alkali liquor, high energy consumption and high production and sewage treatment costs.
Disclosure of Invention
The technical problem to be solved by the invention is as follows: overcomes the defects of the prior art and provides a preparation method of cellulose ether with low alkali consumption and less sewage.
The technical scheme adopted by the invention for solving the technical problems is as follows: the preparation method of the low-whiteness cellulose ether is characterized by sequentially comprising the following steps:
1) crushing: crushing the fiber material into fiber micro powder with the particle size of 50-150 meshes;
2) and (3) cooking: soaking the fiber micro powder obtained in the step 1) into an alkali liquor with the mass concentration of 1.5-15%, and cooking for 20-90 minutes at the cooking temperature of 100-260 ℃;
3) etherification: improving the mass concentration of the alkali liquor in the system to 25-70% on the basis of the step 3), adding a solvent and an etherifying agent, and carrying out etherification reaction;
4) rinsing: and after the etherification reaction is finished, carrying out solid-liquid separation to obtain solid and liquid, and rinsing the solid obtained by the solid-liquid separation.
The main improvement of the invention lies in that the whole cellulose ether step sequence is adjusted, and in the production method, the steps of stewing, etherification and rinsing adopt the prior process conditions and material ratio of the cellulose ether to obtain ideal preparation effect. Compared with the prior art, the preparation method can obtain the similar product with higher viscosity, thereby achieving the prior effect with less addition amount when in use.
According to the preparation method, the fiber material is firstly crushed into the micro powder, and the inventor finds that the fiber material in the micro powder state can achieve a good degumming effect and can more thoroughly elute impurities only by cooking. The product with whiteness completely meeting the industry requirement of building, cement, petroleum and the like with low whiteness can be obtained without bleaching.
In the invention, the fiber micro powder is directly cooked, and the main purpose of the cooking is to further expand and loosen the fiber micro powder, thereby being more beneficial to the efficient and stable performance of etherification reaction. The adjustable range of the alkali liquor concentration during cooking can be larger, and the fault tolerance rate is higher. The greater the concentration of alkali lye in a certain range, the more the fibre can be bulked in a shorter time. The concentration of lye is lower during cooking in the conventional process because the alkali in the fiber needs to be rinsed out completely after cooking in the process. Obviously, the greater the lye concentration, the greater the amount of rinse water required. However, in the invention, the concentration of the alkali liquor is increased to reach the etherification condition by adding alkali or concentrating part of water on the basis of the cooking liquor directly after cooking, so that the rinsing cost is not required to be considered, and the concentration of the cooked alkali liquor can be increased as much as possible without damaging cellulose.
In addition, because the object of the invention is fiber micropowder, and the function of the cooking is only to expand and loosen the fiber, the alkali liquor concentration actually needed for achieving the purpose is lower. That is, in the present invention, the cooking can be performed at a lower alkali solution concentration. However, alkali is directly added on the basis of the cooking liquor after cooking to improve the alkali liquor concentration to reach the etherification condition, no matter the concentration of the cooking liquor is high or low, alkali liquor waste is not caused or the rinsing cost is increased, so that the alkali liquor mass concentration is preferably 10-15% during cooking.
Preferably, the fiber material in the step 1) is cotton linters.
Preferably, the crushing in the step 1) is to add the fiber material and alkali liquor into a wet crusher simultaneously, and crush the fiber material to obtain the fiber slurry with the particle size of 50-150 meshes. The crushing in the invention is preferably carried out by wet crushing, the alkali liquor needed in the cooking process is mixed with the fiber material in advance, and the alkali liquor and the fiber are fully contacted through physical stress while the wet crushing is carried out to obtain the fiber slurry, so that the fiber is degummed more quickly. Water and alkali are directly added into the fiber pulp to reach the concentration of the boiled alkali liquor. After the wet crushing is adopted, overheating and dust cannot be generated in the crushing process, the noise is lower, the production is safer, no dust pollution exists, and the operation environment is optimized.
In the wet crushing process, the proportion of the fiber material and the alkali liquor is not a key factor, and the fiber material in a wet state can also achieve the effects of reducing noise, removing dust and the like. The proportion (which can be set between 10:5 and 200) of the fiber material and the alkali liquor in the crushing in the step 1) is low, and the fault-tolerant capability is high. But in order to increase the fluidity of the slurry, the material transportation cost is reduced. Preferably, the mass ratio of the fiber material to the alkali liquor in the step 1) is 1: 1.3-6.
Preferably, the cooking in step 2) is performed by steaming the fiber soaked in the alkali liquor by using a rotary spherical digester.
Preferably, the alkali in the step 3) is NaOH, and the alkali liquor in the steps 3) and 4) is NaOH solution.
Preferably, the water phase of the liquid subjected to solid-liquid separation in the step 4) is directly cooled to-5-10 ℃ after desolventizing, then the solid-liquid separation is carried out to obtain alkali and a mixed solution, and the mixed solution is concentrated and crystallized to realize desalination. In the etherification reaction system, the concentration of alkali in a higher-temperature water phase obtained after desolventizing (the desolventizing comprises distilling to remove an organic solvent and/or an etherifying agent) is higher, the water phase is saturated or nearly saturated, and the concentration of generated salt is lower. At the moment, the aqueous phase is concentrated and crystallized, and the purity of salt in the obtained solid material can reach more than 85 percent without further treatment, so that the purity is greatly improved.
Preferably, the cooking pressure in the step 2) is 0.3 MPa-0.9 MPa. Because cooking in high-concentration lye can be realized in the present preparation method, the required cooking pressure and cooking temperature can be carried out under lower conditions. More preferably, the cooking pressure in the step 2) is 0.3 MPa-0.4 MPa; the cooking temperature is 110-140 ℃.
Compared with the prior art, the invention has the beneficial effects that: the preparation method of the invention saves the bleaching and rinsing processes before and after the cooking, and simultaneously improves the efficiency of each step, thereby greatly improving the overall production efficiency. The production time required by one batch of cellulose ether with the same yield is only 70% -80% of the time required by the traditional preparation method. In addition, in the preparation method, because the reaction conditions of the steps can be carried out under milder conditions, under the conditions of lower temperature and pressure and fewer production links, under the preferable preparation conditions, the energy consumption required by a batch of cellulose ether with the same yield is only 52-60% of the energy consumption required by the traditional preparation method. Meanwhile, compared with the traditional preparation method, the preparation method disclosed by the invention has the advantages that the water consumption is reduced by 40-45%, and the alkali consumption is reduced by 20-30%.
Detailed Description
The present invention is further illustrated by the following specific examples, wherein hydroxyethyl cellulose is prepared for comparison between examples and comparative examples, because the present invention is not adjusted for the step of etherification, and the reaction raw materials and reaction conditions of etherification can still follow the conditions of conventional preparation methods. With example 1 being the best practice.
Example 1
1) Crushing: simultaneously adding a fiber material (cotton linter) and water into a wet grinder, grinding the fiber material to the particle size of 150 meshes to obtain fiber slurry, wherein the ratio of the fiber material to the water is 1: 3;
2) and (3) cooking: soaking the fiber micro powder obtained in the step 1) into NaOH solution with the mass concentration of 14%, and cooking for 35 minutes at the cooking temperature of 120 ℃ and the cooking pressure of 0.13 MPa;
3) etherification: directly concentrating on the basis of the step 2), improving the mass concentration of alkali liquor in a reaction system to 60%, cooling to 23 ℃, adding an etherifying agent ethylene oxide which is 1.2 times of the mass of the fiber micro powder, and carrying out etherification reaction;
4) rinsing: and after the etherification reaction is finished, carrying out solid-liquid separation, rinsing the solid obtained by the solid-liquid separation to obtain hydroxyethyl cellulose, distilling the liquid obtained by the solid-liquid separation to remove ethylene oxide, directly cooling the water phase to 0 ℃, carrying out solid-liquid separation to obtain NaOH and a mixed solution with the purity of 98.3%, and concentrating and crystallizing the mixed solution to realize desalination. In the embodiment, the steam consumption for producing one ton of hydroxyethyl cellulose is 3.6 tons, the electricity consumption is 975 degrees, and the cellulose yield is 1.47 percent (calculated according to gossypol). The obtained hydroxyethylcellulose was a yellowish powder, and the viscosity of a 2% aqueous solution (20 ℃) of the obtained hydroxyethylcellulose was determined by sampling to be 5660 mPas, with an ash content of 1.2%.
Example 2
1) Crushing: simultaneously adding a fiber material (cotton linter) and water into a wet grinder, grinding the fiber material to obtain a fiber slurry, wherein the ratio of the fiber material to the water is 1: 6;
2) and (3) cooking: soaking the fiber micro powder obtained in the step 1) into NaOH solution with the mass concentration of 15%, and cooking for 30 minutes at the cooking temperature of 110 ℃ and the cooking pressure of 0.13 MPa;
3) etherification: directly concentrating on the basis of the step 2), improving the mass concentration of alkali liquor in a reaction system to 30%, cooling to 22 ℃, adding an etherifying agent ethylene oxide which is 1.1 times of the mass of the fiber micro powder, and carrying out etherification reaction;
4) rinsing: and after the etherification reaction is finished, carrying out solid-liquid separation, rinsing the solid obtained by the solid-liquid separation to obtain hydroxyethyl cellulose, distilling the liquid obtained by the solid-liquid separation to remove ethylene oxide, directly cooling the water phase to-5 ℃, carrying out solid-liquid separation to obtain NaOH and a mixed solution with the purity of 98.3%, and concentrating and crystallizing the mixed solution to realize desalination. In the embodiment, the steam consumption for producing one ton of hydroxyethyl cellulose is 3.8 tons, the electricity consumption is 981 ℃, and the cellulose yield is 1.45 percent (calculated according to gossypol). The obtained hydroxyethylcellulose was a yellowish powder, and the viscosity of a 2% aqueous solution (20 ℃) of the obtained hydroxyethylcellulose was determined by sampling to be 5652 mPas, with an ash content of 1.3%.
Example 3
1) Crushing: simultaneously adding fiber materials (cotton linters) and water into a wet grinder, grinding the fiber materials to obtain fiber pulp with the particle size of 150 meshes, wherein the ratio of the fiber materials to the water is 1: 1.3;
2) and (3) cooking: soaking the fiber micro powder obtained in the step 1) into NaOH solution with the mass concentration of 10%, and cooking for 40 minutes at the cooking temperature of 140 ℃ and the cooking pressure of 0.15 MPa;
3) etherification: directly adding NaOH to improve the mass concentration of the alkali liquor in the reaction system to 45% on the basis of the step 2), cooling to 20 ℃, adding an etherifying agent ethylene oxide of which the mass is 1.3 times that of the fiber micro powder, and carrying out etherification reaction;
4) rinsing: and after the etherification reaction is finished, carrying out solid-liquid separation, rinsing the solid obtained by the solid-liquid separation to obtain hydroxyethyl cellulose, distilling the liquid obtained by the solid-liquid separation to remove ethylene oxide, directly cooling the water phase to 5 ℃, carrying out solid-liquid separation to obtain NaOH and a mixed solution with the purity of 98.1%, and concentrating and crystallizing the mixed solution to realize desalination. In the embodiment, the steam consumption for producing one ton of hydroxyethyl cellulose is 3.9 tons, the electricity consumption is 983 degrees, and the cellulose yield is 1.41 percent (calculated according to gossypol). The obtained hydroxyethylcellulose was a yellowish powder, and the viscosity of a 2% aqueous solution (20 ℃) of the obtained hydroxyethylcellulose was 5597 mPas by sampling and measuring, and the ash content was 2.0%.
Example 4
1) Crushing: simultaneously adding a fiber material (cotton linter) and water into a wet grinder, grinding the fiber material to obtain a fiber slurry with the particle size of 50 meshes, wherein the ratio of the fiber material to the water is 10: 5;
2) and (3) cooking: soaking the fiber micro powder obtained in the step 1) into NaOH solution with the mass concentration of 1.5%, and cooking for 90 minutes at the cooking temperature of 260 ℃ and the cooking pressure of 0.9 MPa;
3) etherification: directly adding NaOH to improve the mass concentration of the alkali liquor in the reaction system to 25% on the basis of the step 2), cooling to 50 ℃, adding an etherifying agent ethylene oxide of which the mass is 1.0 time that of the fiber micro powder, and carrying out etherification reaction;
4) rinsing: and after the etherification reaction is finished, carrying out solid-liquid separation, rinsing the solid obtained by the solid-liquid separation to obtain hydroxyethyl cellulose, distilling the liquid obtained by the solid-liquid separation to remove ethylene oxide, directly cooling the water phase to 10 ℃, carrying out solid-liquid separation to obtain NaOH and a mixed solution with the purity of 99%, and concentrating and crystallizing the mixed solution to realize desalination. In the embodiment, the steam consumption for producing one ton of hydroxyethyl cellulose is 4.1 tons, the electricity consumption is 991 ℃, and the cellulose yield is 1.39% (calculated according to gossypol). The obtained hydroxyethylcellulose was a yellowish powder, and the viscosity of a 2% aqueous solution (20 ℃ C.) of the obtained hydroxyethylcellulose was determined by sampling to be 5432 mPas, and the ash content was 2.6%.
Example 5
1) Crushing: simultaneously adding fiber materials (cotton linters) and water into a wet grinder, grinding the fiber materials to a particle size of 66 meshes to obtain fiber slurry, wherein the ratio of the fiber materials to the water is 10: 200;
2) and (3) cooking: soaking the fiber micro powder obtained in the step 1) into a NaOH solution with the mass concentration of 2%, and cooking for 85 minutes at the cooking temperature of 240 ℃ and the cooking pressure of 0.8 MPa;
3) etherification: directly adding NaOH to improve the mass concentration of the alkali liquor in the reaction system to 70% on the basis of the step 2), cooling to 45 ℃, adding an etherifying agent ethylene oxide of which the mass is 1.2 times that of the fiber micro powder, and carrying out etherification reaction;
4) rinsing: and after the etherification reaction is finished, carrying out solid-liquid separation, rinsing the solid obtained by the solid-liquid separation to obtain hydroxyethyl cellulose, distilling the liquid obtained by the solid-liquid separation to remove ethylene oxide, directly cooling the water phase to 0 ℃, carrying out solid-liquid separation to obtain NaOH and a mixed solution with the purity of 98%, and concentrating and crystallizing the mixed solution to realize desalination. In the present example, the steam consumption for producing one ton of hydroxyethyl cellulose is 4.0 ton, the electricity consumption is 989 ℃, and the cellulose yield is 1.39% (calculated according to gossypol). The obtained hydroxyethylcellulose was a yellowish powder, and the viscosity of a 2% aqueous solution (20 ℃ C.) of the obtained hydroxyethylcellulose was determined by sampling to be 5416 mPas, and the ash content was 3.1%.
Example 6
1) Crushing: putting a fiber material (cotton linter) into a dry-method grinder, and grinding the fiber material to obtain fiber powder with the particle size of 50-150 meshes;
2) and (3) cooking: soaking the fiber micro powder obtained in the step 1) into NaOH solution with the mass concentration of 6%, and cooking for 50 minutes at the cooking temperature of 160 ℃ and the cooking pressure of 0.4 MPa;
3) etherification: directly adding NaOH to improve the mass concentration of the alkali liquor in the reaction system to 55% on the basis of the step 2), cooling to 30 ℃, adding an etherifying agent ethylene oxide of which the mass is 1.1 times that of the fiber micro powder, and carrying out etherification reaction;
4) rinsing: and after the etherification reaction is finished, carrying out solid-liquid separation, rinsing the solid obtained by the solid-liquid separation to obtain hydroxyethyl cellulose, distilling the liquid obtained by the solid-liquid separation to remove ethylene oxide, then directly cooling the water phase to-5-10 ℃, carrying out solid-liquid separation to obtain alkali and a mixed solution, and concentrating and crystallizing the mixed solution to realize desalination. In the embodiment, the steam consumption for producing one ton of hydroxyethyl cellulose is 4.1 tons, the electricity consumption is 990 ℃, and the cellulose yield is 1.41 percent (calculated according to gossypol). The obtained hydroxyethylcellulose was a yellowish powder, and a 2% aqueous solution (20 ℃ C.) of the obtained hydroxyethylcellulose was sampled and determined to have a viscosity of 5298 mPas and an ash content of 3.7%.
The foregoing is directed to preferred embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow. However, any simple modification, equivalent change and modification of the above embodiments according to the technical essence of the present invention are within the protection scope of the technical solution of the present invention.
Claims (8)
1. A preparation method of low-whiteness cellulose ether is characterized by sequentially comprising the following steps:
1) crushing: crushing the fiber material into fiber micro powder with the particle size of 50-150 meshes;
2) and (3) cooking: soaking the fiber micro powder obtained in the step 1) into an alkali liquor with the mass concentration of 1.5-15%, and cooking for 20-90 minutes at the cooking temperature of 100-260 ℃;
3) etherification: improving the mass concentration of the alkali liquor in the system to 25-70% on the basis of the step 3), adding a solvent and an etherifying agent, and carrying out etherification reaction;
4) rinsing: and after the etherification reaction is finished, carrying out solid-liquid separation to obtain solid and liquid, and rinsing the solid obtained by the solid-liquid separation.
2. The method for preparing a low whiteness cellulose ether according to claim 1, wherein the method comprises the following steps: the fiber material in the step 1) is cotton linter.
3. The method for preparing a low whiteness cellulose ether according to claim 1, wherein the method comprises the following steps: the crushing in the step 1) is to add the fiber material and alkali liquor into a wet crusher simultaneously, and crush the fiber material to obtain fiber slurry with the particle size of 50-150 meshes.
4. A process for preparing a low whiteness cellulose ether according to claim 3, wherein: the mass ratio of the fiber material to the alkali liquor in the step 1) is 1: 3-6.
5. The method for preparing a low whiteness cellulose ether according to claim 1, wherein the method comprises the following steps: the cooking in the step 2) is the cooking of the fibers soaked in the alkali liquor through a spherical digester.
6. The method for preparing a low whiteness cellulose ether according to claim 1, wherein the method comprises the following steps: the alkali in the step 3) is NaOH, and the alkali liquor in the step 2) and the step 3) is NaOH solution.
7. The method for preparing a low whiteness cellulose ether according to claim 1, wherein the method comprises the following steps: directly cooling the water phase after the liquid subjected to solid-liquid separation in the step 4) is desolventized to-5-10 ℃, then carrying out solid-liquid separation to obtain alkali and a mixed solution, and concentrating and crystallizing the mixed solution to realize desalination.
8. The method for preparing a low whiteness cellulose ether according to claim 1, wherein the method comprises the following steps: the cooking pressure in the step 2) is 0.3 MPa-0.9 MPa.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010338465.3A CN111320704A (en) | 2020-04-26 | 2020-04-26 | Preparation method of low-whiteness cellulose ether |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010338465.3A CN111320704A (en) | 2020-04-26 | 2020-04-26 | Preparation method of low-whiteness cellulose ether |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111320704A true CN111320704A (en) | 2020-06-23 |
Family
ID=71164618
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010338465.3A Pending CN111320704A (en) | 2020-04-26 | 2020-04-26 | Preparation method of low-whiteness cellulose ether |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111320704A (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102312386A (en) * | 2011-08-29 | 2012-01-11 | 山东海龙股份有限公司 | Boiling method for preparing dissolving pulp by use of bleached chemical paper pulp |
| CN105821701A (en) * | 2016-04-08 | 2016-08-03 | 安徽雪龙纤维科技股份有限公司 | Cotton pulp and preparation method thereof, as well as carboxymethylcellulose and preparation method thereof |
| CN106519043A (en) * | 2016-11-19 | 2017-03-22 | 王芹 | Cellulose ether production technology |
-
2020
- 2020-04-26 CN CN202010338465.3A patent/CN111320704A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102312386A (en) * | 2011-08-29 | 2012-01-11 | 山东海龙股份有限公司 | Boiling method for preparing dissolving pulp by use of bleached chemical paper pulp |
| CN105821701A (en) * | 2016-04-08 | 2016-08-03 | 安徽雪龙纤维科技股份有限公司 | Cotton pulp and preparation method thereof, as well as carboxymethylcellulose and preparation method thereof |
| CN106519043A (en) * | 2016-11-19 | 2017-03-22 | 王芹 | Cellulose ether production technology |
Non-Patent Citations (2)
| Title |
|---|
| 汪多仁: "《有机食品表面活性剂（第1版）》", 30 April 2009, 科学技术文献出版社 * |
| 邵自强等: "《硝化纤维素结构与性能（第1版）》", 30 June 2011, 国防工业出版社 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP7149332B2 (en) | Method for producing cellulose, low-dispersion hemicellulose and lignin-dissociated polyphenols from fibrous biomass | |
| CN102212976B (en) | Method for separating bagasse cellulose from lignin | |
| CN109810232B (en) | Method for papermaking and comprehensive utilization of biomass | |
| CN102747637B (en) | Process for producing cellulose by residues of pomace after pectin extraction | |
| CN109653012B (en) | Method for preparing dissolving pulp by using straws or energy plants | |
| CN103233383A (en) | Production process of purified cotton with super-high viscosity | |
| CN103266358B (en) | Method for degumming ramie | |
| CN108179646A (en) | With the method for plant fiber material production xylose, high-boiling alcohol lignin and fiber | |
| CN108729285B (en) | Method for extracting bagasse hemicellulose through microwave-puffing | |
| CN107303578A (en) | It is a kind of to comprehensively utilize the method that straw prevents and treats industrial pollution | |
| CN103122592A (en) | Method for preparing microcrystalline cellulose from waste cotton | |
| CN105249481A (en) | Method for preparing high-swelling-property dietary fibers from residues generated after folium mori extraction | |
| CN107629130B (en) | Method for preparing microcrystalline cellulose by using cotton stalk bark | |
| CN111472186A (en) | Method for preparing high-quality crop straw dissolving pulp through hydrothermal pretreatment | |
| JP2011135869A (en) | Method for saccharifying cellulose | |
| CN103266357A (en) | Production technology of refining cottons | |
| CN111320705A (en) | Preparation method of high-viscosity cellulose ether | |
| CN111320704A (en) | Preparation method of low-whiteness cellulose ether | |
| CN115637603B (en) | Method for preparing pulp from waste pure cotton fabric, product obtained by method and application of pulp | |
| CN109653009B (en) | Preparation method for producing dissolving pulp from xylose residues | |
| CN111020714B (en) | Green production method of bamboo fiber | |
| CN103880976A (en) | Microwave-assisted extraction method of beet pectin | |
| CN110584137B (en) | Method for preparing insoluble dietary fiber by using apple pomace | |
| CN108330723B (en) | Method for extracting cellulose by utilizing amorpha fruticosa planted in saline-alkali soil | |
| CN106192359A (en) | A kind of production technology of linen cotton |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20200623 |
|
| WD01 | Invention patent application deemed withdrawn after publication |