CN114605562B - Desalting method in sodium carboxymethylcellulose fiber production process - Google Patents
Desalting method in sodium carboxymethylcellulose fiber production process Download PDFInfo
- Publication number
- CN114605562B CN114605562B CN202210154962.7A CN202210154962A CN114605562B CN 114605562 B CN114605562 B CN 114605562B CN 202210154962 A CN202210154962 A CN 202210154962A CN 114605562 B CN114605562 B CN 114605562B
- Authority
- CN
- China
- Prior art keywords
- fiber
- sodium
- salt
- solution
- sodium carboxymethylcellulose
- 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.)
- Active
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
- C08B11/20—Post-etherification treatments of chemical or physical type, e.g. mixed etherification in two steps, including purification
- C08B11/22—Isolation
-
- 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
- C08B11/10—Alkyl or cycloalkyl ethers with substituted hydrocarbon radicals substituted with acid radicals
- C08B11/12—Alkyl or cycloalkyl ethers with substituted hydrocarbon radicals substituted with acid radicals substituted with carboxylic radicals, e.g. carboxymethylcellulose [CMC]
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Biochemistry (AREA)
- Materials Engineering (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Polysaccharides And Polysaccharide Derivatives (AREA)
- Materials For Medical Uses (AREA)
- Artificial Filaments (AREA)
Abstract
The invention belongs to the technical field of sodium carboxymethyl cellulose fibers, and particularly relates to a desalting method in the production process of sodium carboxymethyl cellulose fibers. The invention adopts the hydrolyzed collagen as salting-out agent, and the hydrolyzed collagen and the crude sodium carboxymethylcellulose fiber product form intermolecular force due to hydrogen bond action and Van der Waals force, and have good compatibility; the salt concentration required by salting out is achieved by heating, so that salting out reaction is generated, the solubility of hydrolyzed collagen is reduced, the hydrolyzed collagen is separated out, and the salt generated by alkalization, etherification and neutralization reaction is separated from the surface of sodium carboxymethyl cellulose fiber combined with the hydrolyzed collagen. A small amount of salt can be attached to the crude sodium carboxymethylcellulose fiber product again after salting out, but the adhesive force is very weak, and the salt can be separated by vibrating after being placed in a vibrating screen, so that the desalting efficiency is high, and the process is simple and easy to operate.
Description
Technical Field
The invention belongs to the technical field of sodium carboxymethyl cellulose fibers, and particularly relates to a desalting method in the production process of sodium carboxymethyl cellulose fibers.
Background
The natural cellulose is polysaccharide with the widest distribution and highest content in the natural world, and has very rich sources. The cellulose is modified by means of etherification, esterification, graft copolymerization and the like, so that a series of cellulose derivatives can be obtained. Sodium carboxymethyl cellulose (Na-CMC) is cellulose ether obtained by carboxymethyl cellulose, is odorless, tasteless and nontoxic, and has strong hygroscopicity and stability to light and heat, and the solution is neutral or slightly alkaline white or slightly yellow powder. The cellulose fiber is hydrophilic, has certain water absorbability, but has limited water absorbability, and is easy to adhere to skin in the use process, so that the cellulose fiber is usually prepared into sodium carboxymethyl cellulose fiber, the water absorbability is greatly increased, and then the cellulose fiber is prepared into dressing. The dressing prepared by the method has excellent mechanical property and water absorption property, forms gel after absorbing water, can block invasion of external microorganisms while maintaining the moist environment of the wound surface, is easy to remove from the wound surface, does not adhere to the wound surface, and is beneficial to healing of the wound surface.
The cellulose fiber is prepared into sodium carboxymethyl cellulose fiber, which is generally prepared by reacting cellulose fiber with strong alkali and chloroacetic acid or chloroacetic acid salt under certain conditions, and can be divided into two steps, namely an alkalization reaction and an etherification reaction, wherein the two reactions can be carried out sequentially or can be integrated into one step to be carried out simultaneously. The cellulose fiber has higher crystallinity and is difficult to participate in the reaction, so that the cellulose fiber firstly reacts with strong alkali to generate alkali cellulose with better reaction performance, then subsequently reacts with chloroacetic acid or chloroacetate to generate carboxymethylation, and finally the cellulose fiber is neutralized, washed and dried to prepare the sodium carboxymethyl cellulose fiber.
In the process of manufacturing sodium carboxymethyl cellulose fibers, a large amount of salts such as sodium chloride, sodium glycolate and the like are generated, and some of the salts are attached to the surfaces of the fibers and some of the salts are mixed in fiber gaps, so that the purity of the sodium carboxymethyl cellulose fibers is seriously affected.
In the patent number of CN201310312117.9, the name of the method is that the etherified product enters a washing kettle for neutralization washing, then a centrifugal machine is used for separating liquid, solids enter a second washing kettle for washing, a squeezer is used for squeezing the separated liquid after washing, solids enter a third washing kettle for washing, the separated liquid is squeezed by the squeezer after washing, the solids enter a fourth washing kettle for washing, a centrifugal machine is used for separating the liquid after washing, and the solids enter a drying process, so that the purity of sodium carboxymethyl cellulose is improved, but the method is not suitable for sodium carboxymethyl cellulose fibers, because part of salt is mixed in fiber gaps in the production process, and the sodium carboxymethyl cellulose fibers are difficult to remove by washing.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides a desalting method in the production process of sodium carboxymethylcellulose fibers, which adopts hydrolyzed collagen as a salting-out agent, and salt generated by alkalization, etherification and neutralization reactions is separated from the surface of the sodium carboxymethylcellulose fibers by salting-out reaction, so that the subsequent recovery of sodium salts such as sodium chloride, sodium glycolate and the like is facilitated.
In order to solve the technical problems, the invention adopts the following technical scheme:
a method for desalting sodium carboxymethylcellulose in the production process of sodium carboxymethylcellulose comprises alkalization, addition of hydrolyzed collagen, etherification, salting-out and post-treatment.
S1, alkalization
The cellulose fiber is placed in alkaline ethanol for alkalization treatment, the alkalization time is 30-40min, and the temperature is 20-55 ℃.
Preferably, the alkaline ethanol is an alcohol solution of sodium hydroxide, and the mass fraction of the alkaline ethanol is 30% -35%.
Preferably, the fineness of the cellulose fiber is 1.1-2.0 dtex, and the length is 0.6-10 cm.
S2, adding hydrolytic collagen
And (3) placing the alkalized cellulose fibers into an etherification reaction pot, and spraying a premixed collagen solution while stirring to ensure that the collagen solution is uniformly adhered to the alkalized cellulose fibers.
Preferably, the collagen solution is an aqueous solution of hydrolyzed collagen, and the ratio of water to hydrolyzed collagen in the collagen solution is 75-85:10.
Preferably, the collagen solution is added in an amount of 8-10% of the cellulose fibers.
In order to ensure that the hydrolyzed collagen is uniformly attached to the alkalized cellulose fibers, the hydrolyzed collagen is added before the etherification step, because the sodium salt generated after the etherification has an interfering effect, which seriously affects the attaching effect of the hydrolyzed collagen.
S3, etherification
Adding an etherifying agent into the etherification reaction pot, heating to 63-67 ℃, and stirring for reaction for 60-70min.
Preferably, the etherifying agent is a mixed solution of 95% ethanol solution and chloroacetic acid; the ratio of the 95% ethanol solution to the chloroacetic acid is 10:18-22.
Preferably, the ratio of the addition amount of the etherifying agent to the cellulose fiber is 40-45:10.
S4, salting out
Heating the etherification reaction kettle to 80-85 ℃ and stirring, starting to evaporate the mixed solution of water and ethanol in the etherification reaction kettle, and discharging the evaporated mixed solution into condensation recovery equipment through an exhaust hole of the etherification reaction kettle; and after the mixed solution of water and ethanol in the etherification reaction pot is completely evaporated, salting out is completed, and a crude carboxymethyl cellulose sodium fiber is obtained.
The mixed solution of ethanol and water is evaporated by heating to achieve the salt concentration required for salting-out in the etherification reaction pot.
The hydrolyzed collagen is collagen polypeptide with smaller molecular weight generated by the hydrolysis of collagen, is soluble in water, contains glycine, alanine, glutamic acid, arginine, hydroxyproline and the like, has good acid and alkali resistance, and has strong salting-out sensitivity; the carboxymethyl cellulose sodium macromolecular chain contains a large number of carboxyl groups and hydroxyl groups, and is easy to form hydrogen bonds and Van der Waals force together with hydrophilic groups such as amino groups, hydroxyl groups, carboxyl groups and the like contained in hydrolyzed collagen.
When salting out, the etherification reaction pot is a mixture of a mixed solution of water and ethanol, hydrolyzed collagen, salt and crude carboxymethyl cellulose sodium fiber, in the mixture, the hydrolyzed collagen and the crude carboxymethyl cellulose sodium fiber form intermolecular forces due to hydrogen bond action and Van der Waals force, the hydrolyzed collagen and the crude carboxymethyl cellulose sodium fiber have good compatibility, the salt is only attached to the surface or the gap of the crude carboxymethyl cellulose sodium fiber, and the binding force between the hydrolyzed collagen and the crude carboxymethyl cellulose sodium fiber is far higher than the adhesive force between the salt and the crude carboxymethyl cellulose sodium fiber; most of the mixed solution of water and ethanol is evaporated after heating, the concentration of salt is increased along with the evaporation of the mixed solution, and when the concentration of salt is higher than 15%, salting-out phenomenon occurs, namely, the hydration film layer on the surface of hydrolyzed collagen is destroyed, and meanwhile, the electric charge on the surface is neutralized in a large amount, so that the solubility of the hydrolyzed collagen is reduced, the hydrolyzed collagen is separated out, and the salt is separated from and falls off from the crude sodium carboxymethyl cellulose fiber combined with the hydrolyzed collagen.
S5, post-treatment
And taking out the crude sodium carboxymethylcellulose fiber, putting the crude sodium carboxymethylcellulose fiber into a vibrating screen to start vibrating, and sieving salt out of the screen holes of the vibrating screen to obtain sodium carboxymethylcellulose fiber.
Preferably, the vibrating screen is a flat screen or a cylindrical screen; the mesh number of the vibrating screen is 300-500 meshes.
Preferably, the vibration frequency of the vibration is 900 times/min.
Because the fiber has a certain length, the salt in the fiber is not easy to leak out of the meshes of the vibrating screen, and the salt is in tiny particles, so that the salt is easy to leak out of the meshes of the vibrating screen through vibration, and further the separation of the salt and the fiber can be realized.
By adopting the technical scheme, the invention has the following technical effects:
1. the salt removal method in the production process of the sodium carboxymethyl cellulose fiber provided by the invention adopts the hydrolyzed collagen as a salting-out agent, and the salt generated by the alkalization, etherification and neutralization reaction falls off from the surface of the sodium carboxymethyl cellulose fiber through salting-out reaction, so that the subsequent recovery of sodium salts such as sodium chloride, sodium glycolate and the like is facilitated, the salt removal efficiency is high, the process is simple and easy to operate, and the salt content of the sodium carboxymethyl cellulose fiber after the salt removal is 0.2-0.25%.
2. The hydrolyzed collagen is added before the etherification step, so that the sodium salt generated after the etherification is prevented from interfering, the adhesion effect of the hydrolyzed collagen is seriously influenced, and the hydrolyzed collagen is ensured to be uniformly adhered to the alkalized cellulose fibers.
3. The mixed solution of ethanol and water is evaporated in a heating mode, so that the salt concentration required by salting-out phenomenon in the etherification reaction pot is achieved, and the mixed solution of ethanol and water is discharged into condensation recovery equipment through an exhaust hole of the etherification reaction pot after being gasified.
4. The hydrolyzed collagen is collagen polypeptide with smaller molecular weight generated by the hydrolysis of collagen, is soluble in water, contains glycine, alanine, glutamic acid, arginine, hydroxyproline and the like, has good acid and alkali resistance, and has strong salting-out sensitivity; the carboxymethyl cellulose sodium macromolecular chain contains a large number of carboxyl groups and hydroxyl groups, and is easy to form hydrogen bonds and Van der Waals force together with hydrophilic groups such as amino groups, hydroxyl groups, carboxyl groups and the like contained in hydrolyzed collagen.
5. When salting out, the etherification reaction pot is a mixture of a mixed solution of water and ethanol, hydrolyzed collagen, salt and crude carboxymethyl cellulose sodium fiber, in the mixture, the hydrolyzed collagen and the crude carboxymethyl cellulose sodium fiber form intermolecular forces due to hydrogen bond action and Van der Waals force, the hydrolyzed collagen and the crude carboxymethyl cellulose sodium fiber have good compatibility, the salt is only attached to the surface or the gap of the crude carboxymethyl cellulose sodium fiber, and the binding force between the hydrolyzed collagen and the crude carboxymethyl cellulose sodium fiber is far higher than the adhesive force between the salt and the crude carboxymethyl cellulose sodium fiber; most of the mixed solution of water and ethanol is evaporated after heating, the concentration of salt is increased along with the evaporation of the mixed solution, and when the concentration of salt is higher than 15%, salting-out phenomenon occurs, namely, the hydration film layer on the surface of hydrolyzed collagen is destroyed, and meanwhile, the electric charge on the surface is neutralized in a large amount, so that the solubility of the hydrolyzed collagen is reduced, the hydrolyzed collagen is separated out, and the salt is separated from and falls off from the crude sodium carboxymethyl cellulose fiber combined with the hydrolyzed collagen.
6. After salting out, a small amount of salt can be attached to the crude sodium carboxymethylcellulose fiber again, but the adhesive force is weak, and the crude sodium carboxymethylcellulose fiber can be separated by vibrating after being placed in a vibrating screen.
7. Because the crude sodium carboxymethylcellulose fiber has a certain length, salt in the fiber is mostly fine particles and is easy to leak out of the mesh of the vibrating screen through vibration, and further separation of the salt and the fiber can be realized.
Detailed Description
The invention will be further illustrated with reference to specific examples.
Example 1 a method for desalting sodium carboxymethylcellulose fiber in a production process, comprising the following steps:
s1, alkalization
The cellulose fiber is placed in alkaline ethanol for alkalization treatment, the alkalization time is 30min, and the temperature is 35 ℃.
The alkaline ethanol is an alcohol solution of sodium hydroxide, and the mass fraction of the alkaline ethanol is 30%.
The titer of the cellulose fiber is 1.5dtex, and the length is 4.8cm.
S2, adding hydrolytic collagen
And (3) placing the alkalized cellulose fibers into an etherification reaction pot, and spraying a premixed collagen solution while stirring to ensure that the collagen solution is uniformly adhered to the alkalized cellulose fibers.
The collagen solution is an aqueous solution of hydrolyzed collagen, wherein the ratio of water to hydrolyzed collagen is 80:10.
The addition amount of the collagen solution is 9% of the cellulose fiber.
S3, etherification
Adding an etherifying agent into the etherification reaction kettle, heating to 65 ℃, and stirring for reaction for 60min.
The etherifying agent is a mixed solution of 95% ethanol solution and chloroacetic acid; the ratio of the 95% ethanol solution to the chloroacetic acid is 10:20.
The ratio of the addition amount of the etherifying agent to the cellulose fiber is 42:10.
S4, salting out
Heating the etherification reaction kettle to 85 ℃ and stirring, starting to evaporate the mixed solution of water and ethanol in the etherification reaction kettle, and discharging the evaporated mixed solution into condensation recovery equipment through an exhaust hole of the etherification reaction kettle; and after the mixed solution of water and ethanol in the etherification reaction pot is completely evaporated, salting out is completed, and a crude carboxymethyl cellulose sodium fiber is obtained. .
The mixed solution of ethanol and water is evaporated by heating to achieve the salt concentration required for salting-out in the etherification reaction pot.
S5, post-treatment
And taking out the crude sodium carboxymethylcellulose fiber, putting the crude sodium carboxymethylcellulose fiber into a vibrating screen to start vibrating, and sieving salt out of the screen holes of the vibrating screen to obtain sodium carboxymethylcellulose fiber.
The vibrating screen is a plane screen or a cylinder screen; the mesh number of the vibrating screen is 400 meshes.
The vibration frequency of the vibration is 900 times/min.
Because the fiber has a certain length, the salt in the fiber is not easy to leak out of the meshes of the vibrating screen, and the salt is in tiny particles, so that the salt is easy to leak out of the meshes of the vibrating screen through vibration, and further the separation of the salt and the fiber can be realized.
The salt content of the sodium carboxymethylcellulose fiber prepared in example 1 was 0.2%.
Example 2 a method for desalting sodium carboxymethylcellulose fiber during production, comprising the steps of:
s1, alkalization
The cellulose fiber is placed in alkaline ethanol for alkalization treatment, the alkalization time is 35min, and the temperature is 55 ℃.
The alkaline ethanol is an alcohol solution of sodium hydroxide, and the mass fraction of the alkaline ethanol is 33%.
The titer of the cellulose fiber is 1.1dtex, and the length is 10cm.
S2, adding hydrolytic collagen
And (3) placing the alkalized cellulose fibers into an etherification reaction pot, and spraying a premixed collagen solution while stirring to ensure that the collagen solution is uniformly adhered to the alkalized cellulose fibers.
The collagen solution is an aqueous solution of hydrolyzed collagen, wherein the ratio of water to hydrolyzed collagen is 75:10.
The addition amount of the collagen solution is 8% of the cellulose fiber.
S3, etherification
Adding an etherifying agent into the etherification reaction kettle, heating to 63 ℃, and stirring for reaction for 65min.
The etherifying agent is a mixed solution of 95% ethanol solution and chloroacetic acid; the ratio of the 95% ethanol solution to the chloroacetic acid is 10:18.
The ratio of the addition amount of the etherifying agent to the cellulose fiber is 40:10.
S4, salting out
Heating the etherification reaction kettle to 80 ℃ and stirring, starting to evaporate the mixed solution of water and ethanol in the etherification reaction kettle, and discharging the evaporated mixed solution into condensation recovery equipment through an exhaust hole of the etherification reaction kettle; and after the mixed solution of water and ethanol in the etherification reaction pot is completely evaporated, salting out is completed, and a crude carboxymethyl cellulose sodium fiber is obtained. .
The mixed solution of ethanol and water is evaporated by heating to achieve the salt concentration required for salting-out in the etherification reaction pot.
S5, post-treatment
And taking out the crude sodium carboxymethylcellulose fiber, putting the crude sodium carboxymethylcellulose fiber into a vibrating screen to start vibrating, and sieving salt out of the screen holes of the vibrating screen to obtain sodium carboxymethylcellulose fiber.
The vibrating screen is a plane screen or a cylinder screen; the mesh number of the vibrating screen is 300 meshes.
The vibration frequency of the vibration is 900 times/min.
Because the fiber has a certain length, the salt in the fiber is not easy to leak out of the meshes of the vibrating screen, and the salt is in tiny particles, so that the salt is easy to leak out of the meshes of the vibrating screen through vibration, and further the separation of the salt and the fiber can be realized.
The salt content of the sodium carboxymethylcellulose fiber prepared in example 2 was 0.23%.
Example 3 a method for desalting sodium carboxymethylcellulose fiber during production, comprising the steps of:
s1, alkalization
The cellulose fiber is placed in alkaline ethanol for alkalization treatment, the alkalization time is 40min, and the temperature is 20 ℃.
The alkaline ethanol is an alcohol solution of sodium hydroxide, and the mass fraction of the alkaline ethanol is 35%.
The titer of the cellulose fiber is 2.0dtex, and the length is 0.6cm.
S2, adding hydrolytic collagen
And (3) placing the alkalized cellulose fibers into an etherification reaction pot, and spraying a premixed collagen solution while stirring to ensure that the collagen solution is uniformly adhered to the alkalized cellulose fibers.
The collagen solution is an aqueous solution of hydrolyzed collagen, wherein the ratio of water to hydrolyzed collagen is 85:10.
The addition amount of the collagen solution is 10% of that of cellulose fiber.
S3, etherification
Adding an etherifying agent into the etherification reaction kettle, heating to 67 ℃, and stirring for reaction for 70min.
The etherifying agent is a mixed solution of 95% ethanol solution and chloroacetic acid; the ratio of the 95% ethanol solution to the chloroacetic acid is 10:22.
The ratio of the addition amount of the etherifying agent to the cellulose fiber is 45:10.
S4, salting out
Heating the etherification reaction kettle to 85 ℃ and stirring, starting to evaporate the mixed solution of water and ethanol in the etherification reaction kettle, and discharging the evaporated mixed solution into condensation recovery equipment through an exhaust hole of the etherification reaction kettle; and after the mixed solution of water and ethanol in the etherification reaction pot is completely evaporated, salting out is completed, and a crude carboxymethyl cellulose sodium fiber is obtained.
The mixed solution of ethanol and water is evaporated by heating to achieve the salt concentration required for salting-out in the etherification reaction pot.
S5, post-treatment
And taking out the crude sodium carboxymethylcellulose fiber, putting the crude sodium carboxymethylcellulose fiber into a vibrating screen to start vibrating, and sieving salt out of the screen holes of the vibrating screen to obtain sodium carboxymethylcellulose fiber.
The vibrating screen is a plane screen or a cylinder screen; the mesh number of the vibrating screen is 500 meshes.
The vibration frequency of the vibration is 900 times/min.
Because the fiber has a certain length, the salt in the fiber is not easy to leak out of the meshes of the vibrating screen, and the salt is in tiny particles, so that the salt is easy to leak out of the meshes of the vibrating screen through vibration, and further the separation of the salt and the fiber can be realized.
The sodium carboxymethylcellulose fiber prepared by using example 3 has a salt content of 0.25%.
Comparative example 1
Representative example 1 was selected, the step of adding hydrolyzed collagen was removed, and the rest was identical to example 1, as comparative example 1, specifically as follows:
s1, alkalization
The cellulose fiber is placed in alkaline ethanol for alkalization treatment, the alkalization time is 30min, and the temperature is 35 ℃.
The alkaline ethanol is an alcohol solution of sodium hydroxide, and the mass fraction of the alkaline ethanol is 30%.
The titer of the cellulose fiber is 1.5dtex, and the length is 4.8cm.
S2, etherification
Adding an etherifying agent into the etherification reaction kettle, heating to 65 ℃, and stirring for reaction for 60min.
The etherifying agent is a mixed solution of 95% ethanol solution and chloroacetic acid; the ratio of the 95% ethanol solution to the chloroacetic acid is 10:20.
The ratio of the addition amount of the etherifying agent to the cellulose fiber is 42:10.
S3, evaporating
The temperature of the etherification reaction kettle is raised to 85 ℃, the mixed solution of water and ethanol in the etherification reaction kettle begins to evaporate, and the gasified mixed solution is discharged into condensation recovery equipment through an exhaust hole of the etherification reaction kettle; and (3) after the mixed solution of water and ethanol in the etherification reaction pot is completely evaporated, obtaining a crude product of sodium carboxymethylcellulose fiber.
S4, post-treatment
And taking out the crude sodium carboxymethylcellulose fiber, putting the crude sodium carboxymethylcellulose fiber into a vibrating screen to start vibrating, and sieving salt out of the screen holes of the vibrating screen to obtain sodium carboxymethylcellulose fiber.
The vibrating screen is a plane screen or a cylinder screen; the mesh number of the vibrating screen is 400 meshes.
The vibration frequency of the vibration is 900 times/min.
The salt content of the sodium carboxymethyl cellulose fiber prepared in comparative example 1 was 1.56%.
As can be seen from comparative example 1, the step of adding hydrolyzed collagen is omitted, the desalting effect is slightly poor, the example 1 of adding hydrolyzed collagen has the binding force between the hydrolyzed collagen and the crude sodium carboxymethylcellulose fiber product which is far higher than the adhesive force between salt and the crude sodium carboxymethylcellulose fiber product, the hydrolyzed collagen is separated out through salting-out reaction, the salt is separated from and falls off from the crude sodium carboxymethylcellulose fiber product combined with the hydrolyzed collagen, and the desalting effect is better.
Comparative example 2
Representative example 1 was selected, steps S2 and S3 were sequentially exchanged, and the rest was identical to example 1, as comparative example 2, specifically as follows:
s1, alkalization
The cellulose fiber is placed in alkaline ethanol for alkalization treatment, the alkalization time is 30min, and the temperature is 35 ℃.
The alkaline ethanol is an alcohol solution of sodium hydroxide, and the mass fraction of the alkaline ethanol is 30%.
The titer of the cellulose fiber is 1.5dtex, and the length is 4.8cm.
S2, etherification
Adding an etherifying agent into the etherification reaction kettle, heating to 65 ℃, and stirring for reaction for 60min.
The etherifying agent is a mixed solution of 95% ethanol solution and chloroacetic acid; the ratio of the 95% ethanol solution to the chloroacetic acid is 10:20.
The ratio of the addition amount of the etherifying agent to the cellulose fiber is 42:10.
S3, adding hydrolytic collagen
And (3) placing the alkalized cellulose fibers into an etherification reaction pot, and spraying a premixed collagen solution while stirring to ensure that the collagen solution is uniformly adhered to the alkalized cellulose fibers.
The collagen solution is an aqueous solution of hydrolyzed collagen, wherein the ratio of water to hydrolyzed collagen is 80:10.
The addition amount of the collagen solution is 9% of the cellulose fiber.
S4, salting out
The temperature of the etherification reaction kettle is raised to 85 ℃, the mixed solution of water and ethanol in the etherification reaction kettle begins to evaporate, and the gasified mixed solution is discharged into condensation recovery equipment through an exhaust hole of the etherification reaction kettle; and after the mixed solution of water and ethanol in the etherification reaction pot is completely evaporated, salting out is completed, and a crude carboxymethyl cellulose sodium fiber is obtained.
The mixed solution of ethanol and water is evaporated by heating to achieve the salt concentration required for salting-out in the etherification reaction pot.
S5, post-treatment
And taking out the crude sodium carboxymethylcellulose fiber, putting the crude sodium carboxymethylcellulose fiber into a vibrating screen to start vibrating, and sieving salt out of the screen holes of the vibrating screen to obtain sodium carboxymethylcellulose fiber.
The vibrating screen is a plane screen or a cylinder screen; the mesh number of the vibrating screen is 400 meshes.
The vibration frequency of the vibration is 900 times/min.
The salt content of the sodium carboxymethyl cellulose fiber prepared by comparative example 2 was 1.64%.
The hydrolyzed collagen is added before the etherification step, so that the sodium salt generated after the etherification has an interference effect, the adhesion effect of the hydrolyzed collagen is seriously influenced, and the hydrolyzed collagen is ensured to be uniformly adhered to the alkalized cellulose fibers, thereby achieving the ideal desalting effect; and after etherification, hydrolyzed collagen is added, and the existence of sodium salt as impurities influences the adhesion effect of the hydrolyzed collagen, so that the desalting effect is slightly poor.
Salt content detection methods of examples and comparative examples:
taking 3.0g of each of the sodium carboxymethylcellulose fibers of examples 1-3 and comparative examples 1-2, precisely weighing, placing in a 150ml beaker, adding 30ml of water and 3ml of 30% hydrogen peroxide solution, heating in a water bath for 20 minutes, continuously stirring, cooling to room temperature, adding 60ml of water and 6ml of nitric acid, titrating with silver nitrate titration solution (0.05 mol/L), continuously stirring during titration, and indicating the titration end point by a silver electrode potential method. Each 1ml of silver nitrate titrant (0.05 mol/L) corresponds to 2.922mg of sodium salt.
Table 1 shows the salt content test results of examples 1-3 and comparative examples 1-2.
TABLE 1
| Examples/comparative examples | Consumption of silver nitrate titrant (ml) | Salt content% |
| Example 1 | 2.05 | 0.20 |
| Example 2 | 2.36 | 0.23 |
| Example 3 | 2.57 | 0.25 |
| Comparative example 1 | 16.02 | 1.56 |
| Comparative example 2 | 16.84 | 1.64 |
The proportions are mass proportions, and the percentages are mass percentages, unless otherwise specified; the raw materials are all commercially available.
Finally, it should be noted that: the foregoing description is only a preferred embodiment of the present invention, and is not intended to limit the present invention, but although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that modifications may be made to the technical solutions described in the foregoing embodiments, or equivalents may be substituted for some of the technical features thereof. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (8)
1. A desalting method in the production process of sodium carboxymethylcellulose fibers, which is characterized by comprising the steps of alkalizing, adding hydrolyzed collagen, etherifying, salting out and post-treating;
adding hydrolyzed collagen, putting the alkalized cellulose fibers into an etherification reaction pot, and spraying a premixed collagen solution while stirring;
salting out, namely heating the etherification reaction kettle to 80-85 ℃ and stirring, and evaporating a mixed solution of water and ethanol in the etherification reaction kettle; and after the mixed solution of water and ethanol in the etherification reaction pot is completely evaporated, salting out is completed, and a crude carboxymethyl cellulose sodium fiber is obtained.
2. The method for desalting sodium carboxymethylcellulose fiber in the production process according to claim 1, wherein the alkalization is carried out by placing cellulose fiber in alkaline ethanol for alkalization treatment, wherein the alkalization time is 30-40min, and the temperature is 20-55 ℃;
the alkaline ethanol is an alcohol solution of sodium hydroxide, and the mass fraction is 30% -35%;
the fineness of the cellulose fiber is 1.1-2.0 dtex, and the length is 0.6-10 cm.
3. The method for desalting sodium carboxymethylcellulose fiber in production process according to claim 1, wherein the etherification is carried out by adding etherifying agent into etherification reaction pot, heating to 63-67 deg.C, stirring and reacting for 60-70min.
4. The method for removing salt in the production process of sodium carboxymethyl cellulose fiber according to claim 1, wherein the post-treatment is carried out by taking out the crude sodium carboxymethyl cellulose fiber, putting into a vibrating screen, starting to vibrate, and sieving salt out of the screen holes of the vibrating screen to obtain sodium carboxymethyl cellulose fiber.
5. The method for desalting sodium carboxymethylcellulose fiber produced according to claim 1, wherein the collagen solution is an aqueous solution of hydrolyzed collagen, and the ratio of water to hydrolyzed collagen in the collagen solution is 75-85:10.
6. The method for desalting sodium carboxymethylcellulose fiber produced according to claim 1, wherein the collagen solution is added in an amount of 8-10% of the cellulose fiber.
7. The method for desalting sodium carboxymethylcellulose fiber produced according to claim 4, wherein the etherifying agent is a mixed solution of 95% ethanol solution and chloroacetic acid; the ratio of the 95% ethanol solution to the chloroacetic acid is 10:18-22.
8. The method for desalting sodium carboxymethylcellulose fiber produced according to claim 4, wherein the ratio of the etherifying agent to the cellulose fiber is 40-45:10.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210154962.7A CN114605562B (en) | 2022-02-21 | 2022-02-21 | Desalting method in sodium carboxymethylcellulose fiber production process |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210154962.7A CN114605562B (en) | 2022-02-21 | 2022-02-21 | Desalting method in sodium carboxymethylcellulose fiber production process |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114605562A CN114605562A (en) | 2022-06-10 |
| CN114605562B true CN114605562B (en) | 2023-05-16 |
Family
ID=81859249
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210154962.7A Active CN114605562B (en) | 2022-02-21 | 2022-02-21 | Desalting method in sodium carboxymethylcellulose fiber production process |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114605562B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116695438B (en) * | 2023-08-08 | 2023-10-20 | 潍坊广栗新材料科技有限公司 | Preparation method of carboxymethyl cellulose long fiber with good hydrophilicity |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101942028B (en) * | 2010-09-30 | 2012-02-01 | 华南理工大学 | Method for producing potassium carboxymethylcellulose |
| CN102887956B (en) * | 2012-10-22 | 2015-06-03 | 河北业之源化工有限公司 | Method for preparing technical grade sodium carboxymethylcellulose with high viscosity and high salt resistance |
-
2022
- 2022-02-21 CN CN202210154962.7A patent/CN114605562B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN114605562A (en) | 2022-06-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN114605562B (en) | Desalting method in sodium carboxymethylcellulose fiber production process | |
| CN106478825B (en) | Method for preparing oxidized cellulose for hemostasis in ramie oxidation degumming process | |
| WO2020232863A1 (en) | Method for preparing antibacterial and anti-wrinkle hydrogel and use thereof in textiles | |
| CN105169454A (en) | Composite alginate hydrogel dressing as well as preparation method and application thereof | |
| CN102286252A (en) | Process for producing gelatin by using acid method | |
| CN111518296B (en) | Preparation method of chitosan membrane material | |
| CN108976440B (en) | Method for preparing hydrogel from bagasse hemicellulose | |
| CN103554303B (en) | A kind of method of purifying cm-chitosan | |
| del Carmen Borja-Urzola et al. | Chitosan from shrimp residues with a saturated solution of calcium chloride in methanol and water | |
| CN110804773B (en) | Anionic-cationic polyelectrolyte composite material and salt inhibition preparation process thereof | |
| JPS6219897B2 (en) | ||
| CN101177461B (en) | Preparation of quaternary ammonium N-carboxyetbyl chitosan | |
| CN102886066A (en) | Preparation method of calcium-containing soluble hemostatic material | |
| Liu et al. | Removal of copper by modified chitosan adsorptive membrane | |
| CN107823700A (en) | The preparation method of hemostasis Cellulose/Chitosan complex microsphere | |
| CN101362807A (en) | Process for preparation of cyclodextrin aminoacid derivates | |
| JP3057446B1 (en) | Soluble wound healing hemostatic cellulosic fiber, method for producing the same, and method for hemostatic healing of wound using the same | |
| CN107417801B (en) | Injectable hydrogel and preparation method and application thereof | |
| CN106474524A (en) | A kind of degradable starch sthptic sponge and preparation method thereof | |
| FI67860C (en) | PHOSPHONMETHYLSUBSTITUENT INNEHAOLLANDE VATTENLOESLIGA CELLULOSABLANDETRAR OCH FOERFARANDE FOER FRAMSTAELLNING AV DEM | |
| CN106421886A (en) | Hydrogel dressing for repairing wounds and preparation method of hydrogel dressing | |
| CN108395563B (en) | Preparation method of bacterial cellulose powder | |
| CN112125984A (en) | Preparation method of carboxymethyl chitosan | |
| CN115636882B (en) | Preparation method of lithium carboxymethyl cellulose | |
| JP4868428B2 (en) | Manufacturing method of high purity chitin slurry |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |