CN110452304A - A kind of hydroxypropyl methyl cellulose processing technology - Google Patents
A kind of hydroxypropyl methyl cellulose processing technology Download PDFInfo
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- CN110452304A CN110452304A CN201910771042.8A CN201910771042A CN110452304A CN 110452304 A CN110452304 A CN 110452304A CN 201910771042 A CN201910771042 A CN 201910771042A CN 110452304 A CN110452304 A CN 110452304A
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- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08B—POLYSACCHARIDES; DERIVATIVES THEREOF
- C08B11/00—Preparation of cellulose ethers
- C08B11/193—Mixed ethers, i.e. ethers with two or more different etherifying groups
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Abstract
The invention discloses a kind of processing technologys of hydroxypropyl methyl cellulose, include the following steps: step 1, reaction kettle deoxidation；Step 2, alkalization, etherificate；Step 3, washing；Step 4, post-processing；Step 5, recycling.Alkalization and etherificate are carried out simultaneously in same equipment, reduce equipment investment by hydroxypropyl methyl cellulose processing technology of the invention, the reaction time is substantially reduced, correspondingly reduces the labor intensity of worker, clean operating environment, it is with short production cycle, improve production efficiency and yield.During alkalizing and etherification reaction in addition to the lye that dosage is added, the etherifying agent of next step is added together, they are used as solvent at this time, thus amount of liquid is big in reaction kettle, and solid-to-liquid ratio is reasonable, causes purified cotton alkalization uniform, completely, degree of substitution is high and uniform, stable product quality for etherificate.
Description
Technical field
The invention belongs to cellulose preparation technical fields, and in particular to a kind of hydroxypropyl methyl cellulose processing technology.
Background technique
Hydroxypropyl methyl cellulose belongs to nonionic cellulose compound ether, is a kind of food additives, is commonly used for emulsifying
Agent, thickener, suspending agent and animal gelatin substitute.Hydroxypropyl methyl cellulose is as sluggish, viscoelasticity polymerization
Object has medically played significant role.It often makees lubrication section in ophthalmology, and auxiliary material or excipient can be served as in oral drugs
Agent.Hydroxypropyl methyl cellulose production in the prior art is aged, then under given conditions using squeezing after wood pulp caustic dip liquid
Start two step etherification reactions (propylene oxide hydroxypropyl words and chloromethanes methylation), appropriate salt is then added in 90 DEG C of hot water
Acid and oxalic acid washing material, using dehydration, drying, crushing, final sieving obtains finished product.Processing technology is more many and diverse, production
Period is long, and labour cost is larger, and more using equipment, ultimately causes product cost height.
Summary of the invention
In view of this, can be solved the main purpose of the present invention is to provide a kind of hydroxypropyl methyl cellulose processing technology
Hydroxypropyl methyl cellulose processing technology is many and diverse in the prior art, and the production cycle is long, and labour cost is big, uses asking more than equipment
Topic.
In order to achieve the above objectives, the technical scheme of the present invention is realized as follows:
A kind of processing technology of hydroxypropyl methyl cellulose, includes the following steps:
Step 1, reaction kettle deoxidation；
Step 2, alkalization, etherificate；
Step 3, washing；
Step 4, post-processing；
Step 5, recycling.
In a preferred embodiment, reaction kettle deoxidation in the step 1 are as follows: be passed through N to reaction kettle2, displace
Oxygen, until oxygen content≤0.3% (volume), continues logical N2, make reactor pressure 0.1MPa.
In a preferred embodiment, it alkalizes, be etherified in the step 2 are as follows: by 15~20 parts of wood pulp of 100 mesh
It mixes and is put into reaction kettle with 10~15 parts of lye, carry out quaternization；By 10~12 parts of dimethyl ether, 5~8 parts of propylene oxide,
12~15 parts of chloromethanes and pure water mixing, are fabricated to etherifying agent；Etherifying agent is passed through using using hunger-type continuous charging mode
High pressure constant flow pump is added in reaction kettle, carries out etherification reaction；Alkalization and etherification reaction successively occur in a kettle, is produced
Object A.
In a preferred embodiment, it is washed in the step 3 are as follows: make one or more of hydrochloric acid, oxalic acid
It at cleaning solution, is put into washing kettle, product A is washed in washing kettle.
In a preferred embodiment, it is post-processed in the step 4 are as follows: the product A after step 3 is washed passes through
It is filtered, washed, dries and hydroxypropyl methyl cellulose is made in crushing.
In a preferred embodiment, recycled in the step 5 are as follows: dimethyl ether and chloromethanes in gaseous form into
Enter recovery system, carries out recycling and reusing.
In a preferred embodiment, lye described in the step 2 is sodium hydroxide, potassium hydroxide, hydroxide
There is one kind in lithium aqueous solution, the concentration of lye is 30%~60%, and optimal is 40%~50%.
In a preferred embodiment, 50 DEG C~60 DEG C of alkalization temperature, reaction time 0.5h in the step 2
~2h, 60 DEG C~90 DEG C of etherification temperature, the reaction time is 2h~10h, and optimal is 3h~5h.
In a preferred embodiment, temperature is 80 DEG C~95 DEG C in washing kettle in the step 3.
In a preferred embodiment, it is right when alkalization and etherification reaction successively occurring in the step 2 reaction kettle
Substance in reaction kettle is stirred.
Hydroxypropyl methyl cellulose processing technology of the invention has the following beneficial effects: alkalization and is etherified same
It is successively carried out in equipment, reduces equipment investment, substantially reduce the reaction time, correspondingly reduce the labor intensity of worker, it is clean
Net operating environment, it is with short production cycle, improve production efficiency and yield.
During alkalizing and etherification reaction in addition to the lye that dosage is added, the lower etherificate walked is added by high pressure constant flow pump
Agent, they are used as solvent at this time, thus amount of liquid is big in reaction kettle, and solid-to-liquid ratio is reasonable, lead to purified cotton alkalization uniformly, ether
Change completely, degree of substitution is high and uniform, stable product quality.
Detailed description of the invention
Fig. 1 is the processing technology road according to the hydroxypropyl methyl cellulose processing technology in a kind of embodiment of the disclosure
Line.
Specific embodiment
Hydroxypropyl methyl cellulose processing technology of the invention is made below with reference to the embodiment of the present invention further detailed
Explanation.
It should be noted that in the absence of conflict, the features in the embodiments and the embodiments of the present application can phase
Mutually combination.Below in conjunction with embodiment, the present invention will be described in detail.
It should be noted that term used herein above is merely to describe specific embodiment, and be not intended to restricted root
According to the illustrative embodiments of the application.As used herein, unless the context clearly indicates otherwise, otherwise singular
Also it is intended to include plural form, additionally, it should be understood that, when in the present specification using term "comprising" and/or " packet
Include " when, indicate existing characteristics, step, operation, device, component and/or their combination.
It should be noted that the description and claims of this application and term " first " in above-mentioned attached drawing, "
Two " etc. be to be used to distinguish similar objects, without being used to describe a particular order or precedence order.It should be understood that using in this way
Data be interchangeable under appropriate circumstances, so that presently filed embodiment described herein for example can be in addition to herein
Sequence other than those of diagram or description is implemented.In addition, term " includes " and " having " and their any deformation, it is intended that
Be to cover it is non-exclusive include, for example, containing the process, method, system, product or equipment of a series of steps or units not
Those of be necessarily limited to be clearly listed step or unit, but may include be not clearly listed or for these processes, side
The intrinsic other step or units of method, product or equipment.
For ease of description, spatially relative term can be used herein, as " ... on ", " ... top ",
" ... upper surface ", " above " etc., for describing such as a device shown in the figure or feature and other devices or spy
The spatial relation of sign.It should be understood that spatially relative term is intended to comprising the orientation in addition to device described in figure
Except different direction in use or operation.For example, being described as if the device in attached drawing is squeezed " in other devices
It will be positioned as " under other devices or construction after part or construction top " or the device of " on other devices or construction "
Side " or " under other devices or construction ".Thus, exemplary term " ... top " may include " ... top " and
" in ... lower section " two kinds of orientation.The device can also be positioned with other different modes and (is rotated by 90 ° or in other orientation), and
And respective explanations are made to the opposite description in space used herein above.
As described in Figure 1, a kind of processing technology of hydroxypropyl methyl cellulose of the present invention, includes the following steps:
Step 1, reaction kettle deoxidation；
Step 2, alkalization, etherificate；
Step 3, washing；
Step 4, post-processing；
Step 5, recycling.
Alkalization and etherificate are successively carried out in same equipment, reduces equipment investment, substantially reduces reaction time, phase
The labor intensity of worker should be reduced, clean operating environment is with short production cycle, improves production efficiency and yield.It is alkalizing
During with etherification reaction in addition to the lye that dosage is added, it is additionally added the etherifying agent of lower step, they are used as solvent at this time, because
And amount of liquid is big in reaction kettle, solid-to-liquid ratio is reasonable, and purified cotton is caused to be alkalized uniformly, and completely, degree of substitution is high and uniform for etherificate, produces
Quality is stablized.
Reaction kettle deoxidation in step 1 are as follows: be passed through N to reaction kettle2, oxygen is displaced, until oxygen content≤0.3% (body
Product), continue logical N2, make reactor pressure 0.1MPa.Reaction kettle deoxidation can prevent from aoxidizing in alkalization, etherification procedure
Reaction.
It alkalizes, be etherified in step 2 are as follows: 15 parts~20 parts of wood pulp of 100 mesh are mixed with 10 parts~15 parts lye and is put into instead
It answers in kettle, carries out quaternization；By 10 parts~12 parts dimethyl ether, 5~8 parts of propylene oxide, 12 parts~15 parts chloromethanes and pure water
Mixing, is fabricated to etherifying agent；Etherifying agent is added to reaction by high pressure constant flow pump using using hunger-type continuous charging mode
In kettle, etherification reaction is carried out；Alkalization and etherification reaction successively occur in a kettle, obtains product A.Directly add in a kettle
Enter wood pulp, lye, quaternization complete after add dimethyl ether, chloromethanes and propylene oxide, it is successively complete in same equipment
At alkalization and etherification reaction.Using hunger-type PNEUMATICALLY CONTROLLED PERISTALTIC SOLIDS, i.e., etherifying agent is added to reaction kettle by high pressure constant flow pump
In, the etherifying agent of addition participates in reacting at once, so that adding procedure etherifying agent is kept undersaturated condition, until final etherification reaction is complete
At.Hunger-type PNEUMATICALLY CONTROLLED PERISTALTIC SOLIDS improves the feed way in production process, for flammability hazard material by disposably adding originally
Enter to be changed to a small amount of mode that is continuously added to, improves production security.Temperature, pressure control in reaction process are also all realized
DCS is automatically controlled and long-range monitoring, compared with traditional mode of production side in terms of the feasibility of production, reliability, stability, safety
Formula is significantly improved.
It is washed in step 3 are as follows: cleaning solution is made in one or more of hydrochloric acid, oxalic acid, is put into washing kettle, will be produced
Object A is washed in washing kettle.Due to product A in alkalization, contact lye in etherification procedure, in alkalinity, hydrochloric acid can or oxalic acid to production
Object A is neutralized.
It is post-processed in step 4 are as follows: the product A after step 3 is washed is filtered, washed, dry and hydroxyl is made in crushing
Propyl methocel.By washing, product be hydroxypropyl methyl cellulose suspension, then by filtering will be in suspension
Hydroxypropyl methyl cellulose particle filtering come out, then to hydroxypropyl methyl cellulose carry out hot-air seasoning, through crushing, most
Throughout one's life at hydroxypropyl methyl cellulose.
It is recycled in step 5 are as follows: dimethyl ether and chloromethanes enter recovery system in gaseous form, carry out recycling and reusing.It returns
The gas of receipts system recycling is returned in reaction kettle by condensation, is participated in alkalization and etherification reaction, is improved the utilization rate of raw material,
Environmental pollution or personal injury are caused prevented also from gas discharging.
To guarantee that wood pulp is sufficiently alkalized, and keep lye surplus after reaction as few as possible, lye is hydrogen-oxygen in step 2
Change sodium, potassium hydroxide, have one kind in lithium hydroxide aqueous solution, concentration of lye is 30%~60%, and optimal is 40%~50%.
Lye is few after reaction, the amount for neutralizing the hydrochloric acid that lye is added when can also reduce washing.To improve raw material availability, can reduce
Product cost.
50 DEG C~60 DEG C of alkalization temperature in step 2, the reaction time be 0.5h~2h, 60 DEG C~90 DEG C of etherification temperature, instead
It is 2h~10h between seasonable, optimal is 3h~5h.Quaternization temperature is higher, and alkalization time is longer, obtains hydroxypropyl methyl fiber
Plain viscosity is lower, but too low temperature and less time can make reaction not exclusively influence the purity of hydroxypropyl methyl cellulose.
Temperature is 80 DEG C~95 DEG C in washing kettle in step 3, can make the foreign particle and alkali in hydroxypropyl methyl cellulose
Liquid is washed thoroughly displacement, obtains the hydroxypropyl methyl cellulose of high-purity.
It is right when alkalization and etherification reaction occurring simultaneously in step 2 reaction kettle to guarantee the uniformity and adequacy reacted
Substance in reaction kettle is stirred.
By above-mentioned specific embodiment, 2910,2906,2208 type hydroxypropyl methyl cellulose of Chinese Pharmacopoeia can be obtained,
Specific targets are as follows:
1. character: white or off-white color threadiness or particulate powder, it is odorless；
2. pH value: 5.0-8.0；
3. insoluble matter in water :≤0.5%；
4. loss on drying :≤5.0%；
5. residue on ignition :≤1.5%；
6. heavy metal :≤20mg/kg；
8. arsenic :≤0.0002%；
9. substituent group content:
10. viscosity: 15~50mPa.s (2910,2906), 60000~85000mPa.s (2208).
Embodiment one: N is passed through to reaction kettle2, oxygen is displaced, until oxygen content≤0.3% (volume), continues logical N2, make
Reactor pressure is 0.1MPa.18 parts of wood pulp of 100 mesh are mixed with 12 parts of lye and is put into reaction kettle, quaternization is carried out；
10 parts of dimethyl ether, 6 parts of propylene oxide, 14 parts of chloromethanes and pure water are mixed, etherifying agent is fabricated to；Using continuous using hunger-type
Etherifying agent is added in reaction kettle by feed way by high pressure constant flow pump, carries out etherification reaction.Lye is sodium hydroxide, hydrogen-oxygen
There is one kind in change potassium, lithium hydroxide aqueous solution, the concentration of lye is 45%；Alkalization and etherificate successively occur in a kettle
Reaction, alkalization temperature temperature are 60 DEG C, reaction time 2h, and 90 DEG C of etherification temperature, reaction time 5h obtains product A.By salt
Acid, liquid alkaline and sodium hypochlorite mixing, are made cleaning solution, are put into washing kettle, product A is washed in washing kettle, in washing kettle
Temperature is 85 DEG C.Product A after washing is filtered, washed, dry and hydroxypropyl methyl cellulose is made in crushing.Dimethyl ether and
Chloromethanes enters recovery system in gaseous form, carries out recycling and reusing.
Through analyzing, final hydroxypropyl methyl cellulose finished product obtained in above-described embodiment is that 2910 type hydroxypropyl methyls are fine
Dimension element.
Embodiment two: N is passed through to reaction kettle2, oxygen is displaced, until oxygen content≤0.3% (volume), continues logical N2, make
Reactor pressure is 0.1MPa.15 parts of wood pulp of 100 mesh are mixed with 15 parts of lye and is put into reaction kettle, quaternization is carried out；
10 parts of dimethyl ether, 6 parts of propylene oxide, 13 parts of chloromethanes and pure water are mixed, etherifying agent is fabricated to；Using continuous using hunger-type
Etherifying agent is added in reaction kettle by feed way by high pressure constant flow pump, carries out etherification reaction.Lye is sodium hydroxide, hydrogen-oxygen
There is one kind in change potassium, lithium hydroxide aqueous solution, the concentration of lye is 50%；Occur to alkalize and be etherified simultaneously in a kettle
Reaction, alkalization temperature are 60 DEG C, reaction time 2h, and 90 DEG C of etherification temperature, reaction time 5h obtains product A.By hydrochloric acid,
Liquid alkaline and sodium hypochlorite mixing, are made cleaning solution, are put into washing kettle, product A is washed in washing kettle, temperature in washing kettle
It is 85 DEG C.Product A after washing is filtered, washed, dry and hydroxypropyl methyl cellulose is made in crushing.Dimethyl ether and chloromethane
Alkane enters recovery system in gaseous form, carries out recycling and reusing.
Through analyzing, final hydroxypropyl methyl cellulose finished product obtained in above-described embodiment is that 2906 type hydroxypropyl methyls are fine
Dimension element.
Embodiment three: N is passed through to reaction kettle2, oxygen is displaced, until oxygen content≤0.3% (volume), continues logical N2, make
Reactor pressure is 0.1MPa.20 parts of wood pulp of 100 mesh are mixed with 10 parts of lye and is put into reaction kettle, quaternization is carried out；
12 parts of dimethyl ether, 6 parts of propylene oxide, 14 parts of chloromethanes and pure water are mixed, etherifying agent is fabricated to；Using continuous using hunger-type
Etherifying agent is added in reaction kettle by feed way by high pressure constant flow pump, carries out etherification reaction.Lye is sodium hydroxide, hydrogen-oxygen
There is one kind in change potassium, lithium hydroxide aqueous solution, the concentration of lye is 40%；Occur to alkalize and be etherified simultaneously in a kettle
Reaction, alkalization temperature are 50 DEG C, reaction time 0.5h, and 60 DEG C of etherification temperature, reaction time 2h obtains product A.By salt
Acid, liquid alkaline and sodium hypochlorite mixing, are made cleaning solution, are put into washing kettle, product A is washed in washing kettle, in washing kettle
Temperature is 85 DEG C.Product A after washing is filtered, washed, dry and hydroxypropyl methyl cellulose is made in crushing.Dimethyl ether and
Chloromethanes enters recovery system in gaseous form, carries out recycling and reusing.
Through analyzing, final hydroxypropyl methyl cellulose finished product obtained in above-described embodiment is that 2208 type hydroxypropyl methyls are fine
Dimension element.
The foregoing is only a preferred embodiment of the present invention, is not intended to limit the scope of the present invention.
Claims (10)
1. a kind of processing technology of hydroxypropyl methyl cellulose, which comprises the steps of:
Step 1, reaction kettle deoxidation；
Step 2, alkalization, etherificate；
Step 3, washing；
Step 4, post-processing；
Step 5, recycling.
2. the processing technology of hydroxypropyl methyl cellulose according to claim 1, it is characterised in that: anti-in the step 1
Answer kettle deoxidation are as follows: be passed through N to reaction kettle2, oxygen is displaced, until oxygen content≤0.3%(volume), continue logical N2, make reaction kettle
Pressure is 0.1MPa.
3. the processing technology of hydroxypropyl methyl cellulose according to claim 1, it is characterised in that: alkali in the step 2
Change, etherificate are as follows: 15 parts ~ 20 parts of wood pulp of 100 mesh are mixed and are put into reaction kettle with 10 parts ~ 15 parts lye, quaternization is carried out；
10 parts ~ 12 parts dimethyl ether, 5 parts ~ 8 parts propylene oxide, 12 parts ~ 15 parts chloromethanes and pure water are mixed, etherifying agent is fabricated to；Using
Etherifying agent is added in reaction kettle by high pressure constant flow pump using hunger-type continuous charging mode, carries out etherification reaction；Anti-
It answers and alkalization and etherification reaction successively occurs in kettle, obtain product A.
4. the processing technology of hydroxypropyl methyl cellulose according to claim 1, it is characterised in that: washed in the step 3
It washs are as follows: cleaning solution is made in one or more of hydrochloric acid, oxalic acid, is put into washing kettle, product A is washed in washing kettle.
5. the processing technology of hydroxypropyl methyl cellulose according to claim 1, it is characterised in that: after in the step 4
Processing are as follows: the product A after step 3 is washed is filtered, washed, dry and hydroxypropyl methyl cellulose is made in crushing.
6. the processing technology of hydroxypropyl methyl cellulose according to claim 1, it is characterised in that: returned in the step 5
It receives are as follows: dimethyl ether and chloromethanes enter recovery system in gaseous form, carry out recycling and reusing.
7. the processing technology of hydroxypropyl methyl cellulose according to claim 3, it is characterised in that: institute in the step 2
Lye is stated as the one kind that has in sodium hydroxide, potassium hydroxide, lithium hydroxide aqueous solution, the concentration of lye is 30% ~ 60%, optimal
It is 40% ~ 50%.
8. the processing technology of hydroxypropyl methyl cellulose according to claim 3, it is characterised in that: alkali in the step 2
Change temperature 50 C~60 DEG C, the reaction time is 0.5h~2h, and 60 DEG C~90 DEG C of etherification temperature, the reaction time is 2h~10h, most
Excellent is 3h ~ 5h.
9. the processing technology of hydroxypropyl methyl cellulose according to claim 4, it is characterised in that: washed in the step 3
Washing temperature in kettle is 80 DEG C ~ 95 DEG C.
10. the processing technology of hydroxypropyl methyl cellulose according to claim 3, it is characterised in that: the step 2 is anti-
It answers in kettle when alkalization and etherification reaction successively occurs, the substance in reaction kettle is stirred.
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| CN201910771042.8A CN110452304A (en) | 2019-08-20 | 2019-08-20 | A kind of hydroxypropyl methyl cellulose processing technology |
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Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3544556A (en) * | 1965-12-30 | 1970-12-01 | Kalle Ag | Process for the preparation of cellulose ethers |
| CN103555225A (en) * | 2013-10-11 | 2014-02-05 | 湖州光博生物科技有限公司 | Preparation method for silver ion anti-bacterial glue |
| CN109336984A (en) * | 2018-09-18 | 2019-02-15 | 宁夏宸宇精细化学品有限责任公司 | High viscosity hydroxypropyl methyl cellulose and preparation method thereof |
-
2019
- 2019-08-20 CN CN201910771042.8A patent/CN110452304A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3544556A (en) * | 1965-12-30 | 1970-12-01 | Kalle Ag | Process for the preparation of cellulose ethers |
| CN103555225A (en) * | 2013-10-11 | 2014-02-05 | 湖州光博生物科技有限公司 | Preparation method for silver ion anti-bacterial glue |
| CN109336984A (en) * | 2018-09-18 | 2019-02-15 | 宁夏宸宇精细化学品有限责任公司 | High viscosity hydroxypropyl methyl cellulose and preparation method thereof |
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Application publication date: 20191115 |