CN104153229B - A kind of preparation method of bamboo dissolving pulp - Google Patents
A kind of preparation method of bamboo dissolving pulp Download PDFInfo
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- CN104153229B CN104153229B CN201410339894.7A CN201410339894A CN104153229B CN 104153229 B CN104153229 B CN 104153229B CN 201410339894 A CN201410339894 A CN 201410339894A CN 104153229 B CN104153229 B CN 104153229B
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Abstract
The invention discloses a kind of preparation method of bamboo dissolving pulp, this method uses following production process using bamboo as raw material：Raw material including bamboo chip after acetic acid,diluted prehydrolysis, prehydrolysis carries out sulphate cook, slurry and carries out oxygen delignification, the cold alkali density processing of slurry progress, D0‑(EP)‑D1Bleaching obtains dissolving pulp product.Obtained dissolving pulp brightness is more than 90%ISO, and chemical cellulose content is more than 92%, inherent viscosity 959ml/g, hemi-cellulose content 3.23%, content of ashes 0.11%, and the yield of dissolving pulp is 38%.38 percentage points are at least improved compared to current conventional process (yield 30% 35%), this has very big economic benefit in dissolving pulp production.
Description
Technical field
The present invention relates to pulping process technical field, and in particular to a kind of bamboo fibre dissolving pulp and its production technology.
Background technology
Dissolving pulp is also known as spoelalty pulp, or refined stock, and its main application is used as producing the viscose rayon of textile raw material, simultaneously
Be also glassine paper, pharmaceuticals industry sterilising filtration paper, acetate fiber (cigarette crosses mouth rod raw material), nitrocellulose, carboxymethyl cellulose,
The raw material of the products such as microcrystalline cellulose, cellulose ether.Dissolving pulp is a kind of purer and uniform high-quality chemical pulp, its alpha fibre
Cellulose content is 90%~98%.The traditional raw material for producing dissolving pulp is needlebush and cotton linter, but because domestic timber resources is supplied
Should be not enough, and cotton linter price is larger with market fluctuation, so for a long time, domestic dissolving pulp depends on import.It is molten
The maximum consumption of solution slurry is to prepare viscose rayon to produce artificial silk, as textile material.As domestic market is fine to viscose glue
The rapid growth of demand is tieed up, the yield of dissolving pulp will also keep the trend of a growth.
Although the performance indications that required dissolving pulp is prepared for different product are different, its basic demand is consistent
, i.e., alpha-cellulose content is high and the degree of polymerization is homogeneous, and poly-pentose and impurity content are low.The other raw material production dissolvings of research and utilization
Slurry, can not only solve the problem of dissolving pulp supply is nervous, can also reduce the felling to trees, environmental protection.Bamboo is one
Long fibre lignin raw material is planted, because its chemical composition is close with needlebush, and has the spy that growth cycle is short, yield is high
Point, so being considered as a kind of raw material of the production dissolving pulp of high-quality.In industrial production, although the production technology of dissolving pulp is
Through very ripe, but the product yield that production is obtained is difficult to more than 30%-35% all the time, and this significantly limit enterprise and produces
The control of cost and the increase of profit.So while dissolving pulp product quality is kept, how research improves the yield of product
It is very significant.
The content of the invention
Instant invention overcomes the deficiencies in the prior art, there is provided the preparation of a kind of product yield height, the measured bamboo dissolved pulp of matter
Method.In order to solve the above technical problems, the present invention provides following technical scheme.
A kind of preparation method of bamboo dissolving pulp, comprises the following steps：
(1) bamboo chip is used into dilute acid prehydrolysis, the condition of prehydrolysis is：Diluted acid mass concentration 0.1%-10%, solid-to-liquid ratio
1:5-1:10,130-180 DEG C of temperature, heating-up time 60-150min, soaking time 15-120min；
(2) raw material after prehydrolysis carries out sulphate cook by washing, and conditions of cooking is：Solid-to-liquid ratio 1:5-1:10, steam
Boil 160-180 DEG C of temperature, heating-up time 60-90min, soaking time 30-120min, the mass ratio of sodium hydroxide and bamboo chip is
The mass ratio of 15%-20%, vulcanized sodium and bamboo chip is 4%-8%；The heating-up time refers to be risen to needed for boiling temperature from 80 DEG C
The time wanted；
(3) slurry carries out oxygen delignification, and technique is as follows：By slurry concentration control in 8%-15%, reaction temperature is
80-105 DEG C, the reaction time is 50-90min, and oxygen pressure is 500-800KPa, and sodium hydroxide mass concentration is 1.5%-3%, sulfuric acid
Magnesium mass concentration 0.15%-0.3%；
(4) slurry carries out cold alkali density processing, and technique is as follows：By slurry concentration control in 8%-15%, reaction temperature is
25-50 DEG C, the reaction time is 50-70min, and sodium hydroxide mass concentration is 3%-8%；
(5) slurry carries out D0-(EP)-D1Bleaching, technique is as follows：By slurry concentration control in 8%-15%, reaction temperature
Spend for 60-80 DEG C, the reaction time is 50-200min, Chlorine is 3%-6%, hydrogen peroxide use with respect to oven dry stock
For 0.2-0.4%, sodium hydroxide concentration is 1.0-3.0%.
Diluted acid used is acetic acid in step (1).Preferably, the mass concentration of acetic acid is 0.1%-5%.
Temperature described in step (1) is 140-170 DEG C, and the heating-up time is 60-120min, and soaking time is 15-90min.
The boiling reagent that sulfate process is used in step (2) is sodium hydroxide and vulcanized sodium, wherein sodium hydroxide and bamboo
The mass ratio of piece is 17%-20%, and the mass ratio of vulcanized sodium and bamboo chip is 5%-7%.
Boiling temperature is 160-170 DEG C in step (2), and the heating-up time is 70-90min, and soaking time is 30-90min.
Chemical reagent in step (3) added by oxygen delignification is oxygen, sodium hydroxide, magnesium sulfate, and oxygen pressure is 600-
700KPa, sodium hydroxide mass concentration is 2%-3%, magnesium sulfate mass concentration 0.2%-0.3%；The slurry concentration of oxygen delignification
For 10%-15%, reaction temperature is 90-105 DEG C.
The reaction paste concentration of cold alkali density processing is 10%-15% in step (4), and reaction temperature is 30-50 DEG C, reaction
Time is 50-70min, and sodium hydroxide mass concentration is 5%-8%.
Bleaching uses D in step (5)0-(EP)-D1Three sections of drifts.D represents ClO 2 bleaching, (EP) represent alkali
Property hydrogen peroxide bleaching.The hydrogen peroxide use is 0.3%, sodium hydroxide concentration 1.5%.
Compared with existing dissolving pulp production technology, the advantage of the invention is that：
(1) the dissolving pulp product yield obtained is high, and more other techniques are higher by least 3%-8%.
(2) bamboo chip carries out prehydrolysis using acetic acid,diluted.Compared with traditional dilute sulfuric acid prehydrolysis, there are following 2 benefits：
1st, the acidity of acetic acid is weak compared with sulfuric acid, reduces the corrosion to equipment；2nd, prehydrolysis reaction causes the removing of hemicellulose acetyl group,
Acetic acid can be inherently produced, it can be extracted to serve as the catalysis acid of prehydrolysis reaction, realize following for reagent
Ring is utilized.
(3) addition of acetic acid is reasonable.The addition of certain mass strength acetic acid has been catalyzed the elimination reaction of hemicellulose, drop
Temperature required for low reaction, shortens the reaction time, reduces the energy consumption of preprocessing process.
(4) technological parameter of prehydrolysis and subsequent sulphuric acid salt digestion process sets reasonable, it is ensured that the yield of product.Dissolving
The yield of slurry final products depends primarily on the reaction controlling of prehydrolysis and sulphate cook, and the removing of hemicellulose and lignin needs
Corresponding balance is reached during the two, could not only ensure cooking quality but also yield can be made to reach highest.
(5) oxygen delignification, cold alkali density, D0-(EP)-D1The technological parameter of process sets reasonable, it is ensured that the performance of product
Index reaches requirement.
Embodiment
The invention will be further described with reference to embodiments, but the scope of protection of present invention is not limited to
This.
Embodiment 1
A kind of preparation method of bamboo dissolving pulp, improves implementation steps as follows：Bamboo chip passes through acetic acid,diluted prehydrolysis, sulfate
Boiling, oxygen delignification, cold alkali density, D0-(EP)-D1Bleaching obtains dissolving pulp product.Concrete technology is as shown in table 1.
The technological process of the dissolving pulp of table 1.
The whiteness of the dissolving pulp of gained is 92.24%ISO, and alpha-cellulose is 93.16%, and inherent viscosity is 959ml/g, is gathered
Pentose content is 5.23%, and content of ashes is 0.17%, and yield is 37.26%.
Embodiment 2
As described in Example 1, except that the temperature of prehydrolysis is 170 DEG C, the soaking time of sulphate cook is
60min.The whiteness of the dissolving pulp of gained is 91.6%ISO, and alpha-cellulose is 95.74%, and inherent viscosity is 714ml/g, poly- penta
Sugared content is 4.11%, and content of ashes is 0.11%, and yield is 31.12%.
Embodiment 3
As described in Example 1, except that the temperature of prehydrolysis is 150 DEG C, the soaking time of sulphate cook is
60min.The whiteness of the dissolving pulp of gained is 89.84%ISO, and alpha-cellulose is 87.12%, and inherent viscosity is 951ml/g, poly- penta
Sugared content is 10.01%, and content of ashes is 0.19%, and yield is 38.31%.
Embodiment 4
As described in Example 1, except that the temperature of prehydrolysis is 140 DEG C, the soaking time of sulphate cook is
60min.The whiteness of the dissolving pulp of gained is 90.84%ISO, and alpha-cellulose is 83.12%, and inherent viscosity is 923ml/g, poly- penta
Sugared content is 12.01%, and content of ashes is 0.21%, and yield is 40.31%.
Embodiment 5
As described in Example 1, except that the soaking time of sulphate cook is 60min.The dissolving pulp of gained it is white
Spend for 90.84%ISO, alpha-cellulose is 92.12%, and inherent viscosity is 906ml/g, and hemi-cellulose content is 5.12%, and ash content contains
Measure as 0.11%, yield is 36.31%.
Embodiment 6
As described in Example 1, except that the soaking time of sulphate cook is 90min.The dissolving pulp of gained it is white
Spend for 92.84%ISO, alpha-cellulose is 92.12%, and inherent viscosity is 900ml/g, and hemi-cellulose content is 5.01%, and ash content contains
Measure as 0.11%, yield is 36.31%.
Embodiment 7
As described in Example 1, except that the soaking time of sulphate cook is 120min.The dissolving pulp of gained it is white
Spend for 91.84%ISO, alpha-cellulose is 92.12%, and inherent viscosity is 951ml/g, and hemi-cellulose content is 4.01%, and ash content contains
Measure as 0.11%, yield is 36.11%.
Embodiment 8
As described in Example 1, except that the consumption of acetic acid is 0.1%, the soaking time of sulphate cook is
60min.The whiteness of the dissolving pulp of gained is 89.84%ISO, and alpha-cellulose is 90.12%, and inherent viscosity is 931ml/g, poly- penta
Sugared content is 6.01%, and content of ashes is 0.15%, and yield is 37.31%.
Embodiment 9
As described in Example 1, except that sodium hydroxide is 20% to the percentage of raw material in sulphate cook step,
Vulcanized sodium is 8% to the percentage of raw material, and the soaking time of sulphate cook is 60min.The whiteness of the dissolving pulp of gained is
93.84%ISO, alpha-cellulose is 96.12%, and inherent viscosity is 551ml/g, and hemi-cellulose content is 3.01%, and content of ashes is
0.09%, yield is 30.31%.
Embodiment 10
As described in Example 1, except that sodium hydroxide is 15% to the percentage of raw material in sulphate cook step,
Vulcanized sodium is 4% to the percentage of raw material, and the soaking time of sulphate cook is 60min.The whiteness of the dissolving pulp of gained is
82.84%ISO, alpha-cellulose is 81.12%, and inherent viscosity is 1001ml/g, and hemi-cellulose content is 15.01%, content of ashes
For 0.19%, yield is 42.31%.
Embodiment 11
As described in Example 1, except that prehydrolysis temperature is 140 DEG C, the heating-up time is 120min, sulphate cook
Soaking time be 60min.The whiteness of the dissolving pulp of gained is 89.84%ISO, and alpha-cellulose is 91.12%, and inherent viscosity is
901ml/g, hemi-cellulose content is 6.01%, and content of ashes is 0.15%, and yield is 37.31%.
Embodiment 12
As described in Example 1, except that prehydrolysis temperature is 140 DEG C, soaking time is 120min, sulphate cook
Soaking time be 60min.The whiteness of the dissolving pulp of gained is 92.84%ISO, and alpha-cellulose is 93.12%, and inherent viscosity is
851ml/g, hemi-cellulose content is 6.11%, and content of ashes is 0.15%, and yield is 36.31%.
Embodiment 13
As described in Example 1, except that the boiling temperature of sulphate cook is 170 DEG C, soaking time is 60min.
The whiteness of the dissolving pulp of gained is 91.84%ISO, and alpha-cellulose is 94.12%, and inherent viscosity is 801ml/g, hemi-cellulose content
For 5.11%, content of ashes is 0.12%, and yield is 35.32%.
Embodiment 14
As described in Example 1, except that the soaking time of sulphate cook is 60min, bleaching stage chlorine dioxide
Consumption be 6%.The whiteness of the dissolving pulp of gained is 93.84%ISO, and alpha-cellulose is 95.12%, and inherent viscosity is 851ml/
G, hemi-cellulose content is 3.91%, and content of ashes is 0.11%, and yield is 35.82%.
Embodiment 15
As described in Example 1, except that the soaking time of sulphate cook is 60min, bleaching stage chlorine dioxide
Consumption be 3%.The whiteness of the dissolving pulp of gained is 85.84%ISO, and alpha-cellulose is 88.12%, and inherent viscosity is
1051ml/g, hemi-cellulose content is 9.91%, and content of ashes is 0.17%, and yield is 38.82%.
Claims (9)
1. a kind of preparation method of bamboo dissolving pulp, it is characterised in that comprise the following steps：
(1) bamboo chip is used into dilute acid prehydrolysis, the condition of prehydrolysis is：Diluted acid mass concentration 0.1%-10%, solid-to-liquid ratio 1:5-
1:10,130-180 DEG C of temperature, heating-up time 60-150min, soaking time 15-120min；
(2) raw material after prehydrolysis carries out sulphate cook by washing, and conditions of cooking is：Solid-to-liquid ratio 1:5-1:10, boiling temperature
The mass ratio of 160-180 DEG C of degree, heating-up time 60-90min, soaking time 30-120min, sodium hydroxide and bamboo chip is 15%-
20%, the mass ratio of vulcanized sodium and bamboo chip is 4%-8%；The heating-up time refer to from 80 DEG C rise to required for boiling temperature when
Between；
(3) slurry carries out oxygen delignification, and technique is as follows：By slurry concentration control in 8%-15%, reaction temperature is 80-
105 DEG C, the reaction time is 50-90min, and oxygen pressure is 500-800KPa, and sodium hydroxide mass concentration is 1.5%-3.0%, sulfuric acid
Magnesium mass concentration 0.15%-0.3%；
(4) slurry carries out cold alkali density processing, and technique is as follows：By slurry concentration control in 8%-15%, reaction temperature is 25-50
DEG C, the reaction time is 50-70min, and sodium hydroxide mass concentration is 3%-8%；
(5) slurry carries out D0-(EP)-D1Bleaching, technique is as follows：By slurry concentration control in 8%-15%, reaction temperature is
60-80 DEG C, the reaction time is 50-200min, and Chlorine is 3%-6% with respect to oven dry stock, and hydrogen peroxide use is
0.2-0.4%, sodium hydroxide concentration is 1.0-3.0%.
2. according to the method described in claim 1, it is characterised in that diluted acid used is acetic acid in step (1).
3. method according to claim 2, it is characterised in that the mass concentration of acetic acid is 0.1%-5%.
4. the method according to claim 1 or 2 or 3, it is characterised in that temperature described in step (1) is 140-170 DEG C,
Heating-up time is 60-120min, and soaking time is 15-90min.
5. the method according to claim 1 or 2 or 3, it is characterised in that the quality of sodium hydroxide and bamboo chip in step (2)
Than for 17%-20%, the mass ratio of vulcanized sodium and bamboo chip is 5%-7%.
6. the method according to claim 1 or 2 or 3, it is characterised in that boiling temperature is 160-170 DEG C in step (2),
Heating-up time is 70-90min, and soaking time is 30-90min.
7. the method according to claim 1 or 2 or 3, it is characterised in that the slurry concentration of oxygen delignification is in step (3)
10%-15%, reaction temperature is 90-105 DEG C, and oxygen pressure is 600-700KPa, and sodium hydroxide mass concentration is 2%-3%, sulfuric acid
Magnesium mass concentration 0.2%-0.3%.
8. the method according to claim 1 or 2 or 3, it is characterised in that the reaction slurry of cold alkali density processing in step (4)
Material concentration is 10%-15%, and reaction temperature is 30-50 DEG C, and the reaction time is 50-70min, and sodium hydroxide mass concentration is 5%-
8%.
9. the method according to claim 1 or 2 or 3, it is characterised in that hydrogen peroxide use is described in step (5)
0.3%, sodium hydroxide concentration 1.5%.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
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| RU2763878C1 (en) * | 2020-11-30 | 2022-01-11 | Акционерное общество "Научно-производственное объединение "БИОТЕХКОМПОЗИТ" | Method for obtaining cellulose for chemical processing from cellulose-containing raw materials |
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| CN104863004B (en) * | 2015-04-23 | 2017-04-12 | 中国制浆造纸研究院 | Cotton brei pulp preparation and pollution treatment method |
| CN106436412A (en) * | 2015-08-08 | 2017-02-22 | 四川信联融创实业有限公司 | Preparation method of unbleached neosinocalamus affinis paper pulp |
| CN107696194A (en) * | 2017-11-24 | 2018-02-16 | 广西博白焕发工艺品有限公司 | It is a kind of to retain the blue or green bamboo cane processing method of the natural bamboo of bamboo |
| CN108867130A (en) * | 2018-04-26 | 2018-11-23 | 天津科技大学 | The pulping process of high yield pulp1 needlebush dissolving pulp and its dissolving pulp of preparation |
| CN108951254A (en) * | 2018-07-09 | 2018-12-07 | 广西大学 | A kind of method that bamboo hemicellulose efficiently separates |
| CN112431055A (en) * | 2020-11-16 | 2021-03-02 | 陕西科技大学 | Novel process for preparing dissolving pulp from chemical pulp for papermaking |
| CN112482069B (en) * | 2020-11-24 | 2022-09-23 | 中国林业科学研究院林产化学工业研究所 | Method for preparing high-yield dissolving pulp by using eutectic solvent |
| CN116761914A (en) * | 2021-01-22 | 2023-09-15 | 东丽株式会社 | Wet nonwoven fabric sheet |
| CN113319959B (en) * | 2021-05-27 | 2022-07-15 | 南京林业大学 | Preparation method of microfibrillated bamboo wood |
| CN114606788A (en) * | 2022-03-07 | 2022-06-10 | 华南理工大学 | Method for synchronously preparing dissolving pulp and furfural from wood fibers |
| CN114808512B (en) * | 2022-04-26 | 2023-07-04 | 赣南师范大学 | Bamboo dissolving pulp suitable for alkali urea system and preparation method thereof |
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| CN1410627A (en) * | 2002-09-16 | 2003-04-16 | 成都春天绿竹资源开发有限责任公司 | Production technology of pure natural antibacterial bamboo paste |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1410627A (en) * | 2002-09-16 | 2003-04-16 | 成都春天绿竹资源开发有限责任公司 | Production technology of pure natural antibacterial bamboo paste |
Non-Patent Citations (1)
| Title |
|---|
| 竹子生产溶解浆;李洪才等;《国际造纸》;20120815;第31卷(第4期);1.1-1.4，2.2-2.3，表1，表7 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2763878C1 (en) * | 2020-11-30 | 2022-01-11 | Акционерное общество "Научно-производственное объединение "БИОТЕХКОМПОЗИТ" | Method for obtaining cellulose for chemical processing from cellulose-containing raw materials |
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