CN1166553A - Process for deflingification and/or bleaching of paper pulp - Google Patents
Process for deflingification and/or bleaching of paper pulp Download PDFInfo
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- CN1166553A CN1166553A CN 97110725 CN97110725A CN1166553A CN 1166553 A CN1166553 A CN 1166553A CN 97110725 CN97110725 CN 97110725 CN 97110725 A CN97110725 A CN 97110725A CN 1166553 A CN1166553 A CN 1166553A
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- acid
- paper pulp
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- peroxide
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- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/10—Bleaching ; Apparatus therefor
- D21C9/1026—Other features in bleaching processes
- D21C9/1036—Use of compounds accelerating or improving the efficiency of the processes
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/10—Bleaching ; Apparatus therefor
- D21C9/16—Bleaching ; Apparatus therefor with per compounds
- D21C9/166—Bleaching ; Apparatus therefor with per compounds with peracids
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- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Wood Science & Technology (AREA)
- Paper (AREA)
Abstract
The invention relates to process for the improvement in the selectivity of the delignification and/or bleaching of a preferably chemical paper pulp by means of a peroxyacid, according to which the pulp is treated with an aqueous solution of this organic peroxyacid in the presence of at least one ancillary agent for viscosity protection, selected from inorganic acids of phosphorus and their alkali metal salts, preferably pyrophosphoric acid, sodium pyrophosphates and their ammonium salts.
Description
The present invention relates to the paper pulp that contains lignin be carried out improving one's methods of selectivity delignification and/or bleaching by organic peroxide acid; Wherein, this paper pulp is handled with this organic peroxy aqueous acid in the presence of auxiliary agent.
Knew already that a series of delignification and/or bleaching processing were applicable to and particularly are applicable to the chemical pulp that obtains by the boiling to cellulosic-based material by paper pulp in the presence of chemical reactor, use oxidizing chemical in these processing sections.Usually, first section the purpose that is used for the chemical pulp bleaching schedule is to improve the delignification that does not float paper pulp that directly obtains from steaming stage.This first delignification stages normally is used in the chlorine that applies in the acid medium, chlorine dioxide or brown stock is carried out with the two mixture, so that react with the residual lignin in the paper pulp, and produce can extracting goes out from this paper pulp by the dissolution in processing section subsequently product.
Owing to relate to the various reasons of enhancement of environment, now used the more favourable no chlorine chemistry reactant of environment is replaced chloride chemical reactor in large quantities.For example, in Japanese patent application 55/94811, described by the processing of oxygen delignification to sulfate pulp, this method is included in the existence of additive such as diethylene-triamine pentaacetic acid (DTPA) and uses the peracetic acid section down.
According to European patent application EP-A-578305, paper pulp is handled with peroxy acid in the presence of the stabilizing agent that is selected from phosphonic acids and salt thereof, and this method has the effect that improves delignification selectivity.
Usually, have chelating agent and/or stabilizing agent in delignification stages, make it to avoid the obvious degradation of cellulose chain in the paper pulp, this degraded is to cause cellulose viscosity main reasons for decrease.Although these protectant effects are undeniable, their effect can not reach enough degree, and is especially all the more so for the production quality pulp.
After delignification stages, usually by a kind of or some kinds especially be selected from chlorine dioxide, ozone, the oxidant of hydrogen peroxide and peracetic acid is bleached this paper pulp.These bleaching operations are carried out in the presence of cellulosic protective agent usually, to avoid cellulosic degraded, described protective agent such as magnesium sulfate.
Yet because cellulosic palliating degradation degree is still very high, therefore, the method for Miao Shuing can not make it to obtain enough high-quality paper pulp in the prior art.
Therefore, the applicant has attempted to eliminate this shortcoming.
Therefore; theme of the present invention is the delignification and/or the method for bleaching of paper pulp; this method comprises at least one processing section by organic peroxide acid; it is characterized in that; described processing is carried out in the presence of a kind of or the some kinds of auxiliary agents that are used for the protection sheet slurry viscosity, and described auxiliary agent is selected from the inorganic acid of phosphorus and their salt.
The inorganic acid of phosphorus refers to the acid that does not contain C; The inorganic acid that can mention is for example phosphorous acid, phosphoric acid, pyrophosphoric acid and polyphosphoric acid.
The inorganic acid salt of phosphorus refers to phosphoric acid, wherein, and with one or more conversion salify, especially alkali metal salt of these acidic functionalities.
The paper pulp of the available any kind of of this method (theme of the present invention) carries out, no matter they are chemical pulps, mechanical pulp still is a reuse paper pulp; For example so-called " sulfate pulp " paper pulp.
Paper pulp refers to the material of any cellulose base fiber that obtains from timber, belongs to for example different types of pine tree, fir or dragon spruce no matter they are so-called " needles "; Still so-called " broad-leaved " belongs to, for example different types of hornbeam, white poplar, beech, birch, white poplar, Oak Tree or eucalyptus or their mixture.These paper pulp also can be from various so-called annual plants such as different types of mestha, Corchorus, and bamboo obtains in the reed; Or for example obtain millet straw such as wheat straw or straw or the bagasse from the part plant.In addition, also can pass through reuse paper such as newspaper, magazine paper, packing board, newsprint and writing paper and the copy paper that especially forms office waste, data are handled the processing again of the broken in output paper and the paper-making process and are obtained paper pulp.
Organic peroxide acid refers to, and wherein at least one carboxyl functional group is changed into percarboxylic acids or the polycarboxylic acid of carboxylic group-C (O)-O-OH by peroxide.The example of this class peroxy acid that can mention particularly, the alkanoic acid of crossing that contains 1-10 carbon atom, the single peroxide alkanedioic acid that contains 1-10 carbon atom, the single peroxide alkene bisgallic acid that contains 1-10 carbon atom, the diperoxy alkanedioic acid that contains 1-10 carbon atom, wherein aryl is represented the peroxide aryl dicarboxylic acid or the diperoxy aryl-dicarboxylic acids of phenyl or naphthyl group.The example of these aromatic acids that can mention is benzoyl hydroperoxide, single peroxide phthalic acid, diperoxy phthalic acid or peroxide naphthoic acid.
In first preferred embodiment of the present invention, the auxiliary agent of protection sheet slurry viscosity is a pyrophosphoric acid, sodium pyrophosphate, triphosphoric acid or sodium tripolyphosphate.
In second preferred embodiment of the present invention, organic peroxide acid is selected from: performic acid, peracetic acid, 1,6-diperoxy adipic acid, 1, the single peroxide butene dioic acid of 4-, 1, single peroxysuccinic acid of 4-and benzylhydroperoxide.
Prepare peroxy acid according to the procedure known to those skilled in the art.Peracetic acid or can react acquisition according to following balanced type particularly by aqueous hydrogen peroxide solution and acetate:
Employed peroxy acid or can be pure perhaps preferably can be to contain this peroxide aqueous acid that at least 4% weight randomly is mixed with corresponding organic acid and/or hydrogen peroxide.The preferred peracetic acid aqueous solution that uses, this solution or when balance the mixture of hydrogen peroxide and acetate, perhaps obtain by azeotropic distillation.
In the 3rd preferred embodiment of the present invention, organic peroxide acid is the peracetic acid aqueous solution that contains the described peroxy acid of at least 4% weight, the especially aqueous solution when balance, and this solution also contains hydrogen peroxide in addition, with the weight ratio that causes hydrogen peroxide/peracetic acid greater than 0.5, especially greater than 1.
These solution that can obtain from the market comprise for example following percentage by weight:
| Peracetic acid | 6.2％ | 4.2％ | 15.2％ | 5.2％ | 15.6％ | 16.5％ | 4.4％ |
| Hydrogen peroxide | 22％ | 28.5％ | 23％ | 14.1％ | 14.6％ | 10％ | 37％ |
This peroxy acid also can produce on the spot.
This peroxy acid solution can contain the strong acid of at least 0.1% weight, as, sulfuric acid, nitric acid, phosphoric acid, methanesulfonic acid, or these sour mixtures and about at the most 3% weight.In addition, also can by with mixture and the heterogeneous acid catalyst of hydrogen peroxide and acid for example sulfonated polystyrene contact and make peroxy acid.
According to another embodiment of the invention, can be with sodium metasilicate and/or magnesium salts or magnesium compound such as magnesia, magnesium carbonate, magnesium sulfate or magnesium chloride add in the paper pulp.
Preferably between 20 ℃ and 140 ℃, especially between 50 ℃ and 120 ℃, preferably between 70 ℃ and 90 ℃, and under pressure, preferably, especially, handle with this peroxy acid being lower than 5 crust being less than or equal to about 10 crust.Particularly, the pressurization of reactor available air, or with containing greater than 21% oxygen, especially the gas of at least 80% oxygen pressurizes.
The PH of this section of handling with peroxy acid can be acid, neutral or alkaline, but preferably selects PH between 5 and 9, more preferably between 7 and 8.5.The time of this processing section will be less than 4 hours, preferably less than 2 hours, especially less than 60 minutes.In a preferred alternative of the present invention, the processing of using peroxy acid is at first at 40-100 ℃, and PH2-7, especially 4-6 carried out less than 4 hours, especially less than 2 hours, were preferably 1 hour or shorter; Then, under the washing this paper pulp is not alkalized to PH8-12 in the middle of have, especially at 9.5-12, and 60-120 ℃ of placement less than 4 hours.
Usually, the paper pulp of representing with dry substance is as the criterion, and paper pulp per ton will use the peroxy acid of 3kg at least, preferably uses the peroxy acid of 8kg at least.
This processing can be carried out in the presence of the silicate of cellulosic protective agent such as magnesium salts and alkali metal and alkaline-earth metal.
Usually, need not before the organic peroxide acid processing section, to add washing or decontamination pretreatment section by acidic aqueous solution.The purpose of this washing or pretreatment section is that extracting goes out the impurity that exists with the metal ion form from paper pulp; Described metal ion is harmful to the good process of bleaching and/or delignification operation usually.
According to the present invention, by the delignification of peroxy acid normally to the oxygen delignification of the delignification of paper pulp commonly used and/or bleaching Duan Ruyong ozone or additional with the delignification of chlorine dioxide and/or bleaching section.In addition, also can use the peracetic acid that is present in the bleaching liquid (peroxy acid residue), handle for example bleaching the upstream of delignification stages.
According to the preferred embodiment of the invention, produce in the cleaning solution of peroxy acid from the processing section of paper pulp subsequently.
By the following examples, can understand the present invention better, these given embodiment also do not mean that the present invention is had any qualification.
Embodiment 1
When equilibrium state, with peracetic acid sulfate pulp to be handled, the initial Kappa number of described slurries is 24.2, the viscosity of representing with the degree of polymerization (Dp) is 1480.With respect to dry pulp, the charge amount of peracetic acid and hydrogen peroxide is 3% weight; Then, at 90 ℃ paper pulp is contacted 2 hours with the auxiliary agent that is 0.5% weight with respect to paper pulp, is used for viscosity protection.After this is handled, wash paper pulp with water, in alkaline medium, contact 1 hour in 90 ℃ then, and water carries out final washing again with the soda that with respect to dry pulp is 3% weight.The characteristic value of the paper pulp that so obtains is as follows:
Table 1
| Complexant | Kappa number | Dp (degree of polymerization) |
| - | 13.8 | 1016 |
| EDTA | 16.1 | 1009 |
| DTPA | 14.5 | 1055 |
| DEQUEST2010 | 13.4 | 1350 |
| Pyrophosphate | 12.9 | 1300 |
1) has found that when comparing with contrast test, sodium pyrophosphate has better delignification to paper pulp, and can not produce significantly loss the physical property of the paper pulp represented with Dp.
2) also find in addition, the chelating agent that is used for metal ion that has the amino carboxylic acid structure and use in the processing with hydrogen peroxide usually has adverse influence as EDTA (ethylene diaminetetraacetic acid) and DTPA (diethylene-triamine pentaacetic acid) to delignification.
3) also find at last, can advantageously use sodium pyrophosphate, rather than contain 1-hydroxy ethylene amino-1-dimethylene phosphoric acid HEDP (as the product of selling with trade name Dequest2010) of 40%.
Embodiment 2-5
In the following embodiments, use following various inorganic polyphosphate:
-sodium polyphosphate, pyrophosphoric acid, three polyphosphoric acid, five sodium and calgon.
Handled paper pulp has following characteristic:
-Kappa number: 24.2
-the degree of polymerization: 1510.
This processing is carried out in following mode with following solution:
The peracetic acid of-3% weight,
The hydrogen peroxide of-3.4% weight.
This solution is heated to 90 ℃, and with 10% the dense processing of slurry 3 hours.The percent by volume that following table 2 has been summarized with the auxiliary agent that is used for the viscosity protection is the various values that function obtains, and Kappa number is wherein arranged, the degree of polymerization, the percentage of the percentage of the hydrogen peroxide that is consumed and the peracetic acid that is consumed.
Table 2
| Additive | Auxiliary agent % | Kappa number | Dpv | The H that is consumed 2O 2 | The peracetic acid % that is consumed | |
| Comparative Examples | 0 | 10.1 | 504 | 1.7％ | 3 | |
| Embodiment 2 | Sodium pyrophosphate | 0.1 | 10.3 | 984 | 1.6％ | 3 |
| Sodium pyrophosphate | 0.2 | 10.4 | 1228 | 1.1％ | 3 | |
| Sodium pyrophosphate | 0.4 | 10.6 | 1367 | 0.9％ | 3 | |
| Sodium pyrophosphate | 0.5 | 10.6 | 1324 | 1.2％ | 3 | |
| Sodium pyrophosphate | 0.7 | 10.3 | 1318 | 1.1％ | 3 | |
| Embodiment 3 | Pyrophosphoric acid | 0.5 | 9.1 | 1165 | 1.4％ | 3 |
| Embodiment 4 | Sodium tripolyphosphate | 0.5 | 10.5 | 1327 | 1％ | 3 |
| Embodiment 5 | Calgon | 0.5 | 9 | 1240 | 1.2％ | 3 |
Embodiment 6
Condition according to following table 3 general introductions is handled.Carry out this processing charge amount with dry pulp the be as the criterion peracetic acid of 3% weight and the hydrogen peroxide of 3.3% weight.
Table 3
| Condition | Sodium pyrophosphate with 0.5% is handled | Comparative Examples (not having pyrophosphate) | ||
| Kappa number | Dpv | Kappa number | Dpv | |
| ?90℃，3h | 10.3 | 1324 | 10.1 | 504 |
| ?90℃，2h | 12.8 | 1300 | 13.8 | 1000 |
| ?110 ?℃，1h | 14.9 | 1244 | 15.6 | 1127 |
In the above-described embodiments, be pointed out that polyphosphate that all are tested and that be dissolved in the bleaching liquid has all provided good result.Wherein sodium pyrophosphate concentrates, the optimum amount of this material with respect to dry pulp between 0.2% and 0.5% weight.
Embodiment 7
In 90 ℃, PH equals 4, in the presence of sodium pyrophosphate, with peracetic acid and the hydrogen peroxide aqueous solution when the balance to initial Kappa number (KNo.) be 24 and the degree of polymerization (Dp) be that 1510 chemical pulp was handled 1 hour; For dry pulp, the charge amount of peracetic acid and hydrogen peroxide is respectively 3% and 3.3% weight; The charge amount of sodium pyrophosphate is 0.5% weight.
Then, this paper pulp is divided into two parts.
Soda with about 5% is handled first part of paper pulp, rises to 10.5 to cause PH, continues reaction 2 hours then.
Water washs second part of paper pulp (Comparative Examples), handles 1 hour with soda at 90 ℃ then.
Obtain following result:
Table 4
| Paper pulp before handling | First part of paper pulp (test) after the processing | Second part of paper pulp (contrast) after the processing | |
| Kappa number | 24 | 6.2 | 14.4 |
| Dp | 1510 | 1124 | 1487 |
Embodiment 8
Similar when following step to example 7, and when the magnesium sulfate by extra interpolation 0.2% improves the processing section of first part of paper pulp (test), obtain following result:
Table 5
| Paper pulp before handling | First part of paper pulp (test) after the processing | Second part of paper pulp (Comparative Examples) after the processing | |
| Kappa number | 24.8 | 8.6 | 16.7 |
| Dp | 1450 | 1195 | 1409 |
Embodiment 7 and 8 result have shown at first the extra advantage of handling then rising PH under without any the centre washing at acid PH with peroxy acid.This will increase delignification when keeping the acceptable degree of polymerization.
Claims (11)
1. the delignification of a paper pulp and/or method for bleaching; comprise at least one processing section by organic peroxide acid; it is characterized in that described processing section carries out in the presence of a kind of or the some kinds of auxiliary agents that are used for the protection sheet slurry viscosity, described auxiliary agent is selected from the inorganic acid of phosphorus and their salt.
2. according to the process of claim 1 wherein, the auxiliary agent that is used for the protection sheet slurry viscosity is a pyrophosphoric acid, sodium pyrophosphate, triphosphoric acid or sodium tripolyphosphate.
3. according to the method for claim 1 and 2, wherein, organic peroxide acid is selected from: performic acid, peracetic acid, 1,6-diperoxy adipic acid, 1, the single peroxide butene dioic acid of 4-, 1, single peroxysuccinic acid of 4-and benzylhydroperoxide.
4. according to the method for claim 3, wherein, organic peroxide acid is the peracetic acid aqueous solution that contains the described peroxy acid of at least 4% weight, especially the aqueous solution when balance, this solution also contains hydrogen peroxide in addition, with the weight ratio that causes hydrogen peroxide/peracetic acid greater than 0.5, especially greater than 1.
5. according to the method for one of claim 1-4, wherein, can be at described processing section with sodium metasilicate and/or magnesium salts or magnesium compound such as magnesia, magnesium carbonate, magnesium sulfate or magnesium chloride add in the paper pulp.
6. according to the method for one of claim 1-5, between 20 ℃ and 140 ℃, especially between 50 ℃ and 120 ℃, preferably under the temperature between 70 ℃ and 90 ℃, handle.
7. according to the method for claim 6,, especially under the pressure that is lower than 5 crust, handle being less than or equal to about 10 crust.
8. according to the method for claim 7, using air pressurized, or, especially handling in the reactor that the gas of at least 80% oxygen pressurizes with containing greater than 21% oxygen.
9. according to the method for claim 7 or 8, between 5 and 9, especially between 7 and 8.5, handle at pH value.
10. according to the method for claim 7 or 8, wherein, at first at 40-100 ℃, PH2-7, especially 4-6 carried out less than 4 hours, especially less than 2 hours, were preferably 1 hour or shorter peroxy acid processing; Then, under the washing this paper pulp is not alkalized to PH8-12 in the middle of have, especially at 9.5-12, and 60-120 ℃ of placement less than 4 hours.
11. the method according to one of claim 1-10 is characterized in that, produces in the cleaning solution of peroxy acid from pulp processing section subsequently.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR9604628 | 1996-04-12 | ||
| FR9604628A FR2747408B1 (en) | 1996-04-12 | 1996-04-12 | PROCESS FOR THE DELIGNIFICATION AND / OR BLEACHING OF A PULP |
| FR9612568 | 1996-10-15 | ||
| FR9612568A FR2754550B1 (en) | 1996-10-15 | 1996-10-15 | PROCESS FOR THE DELIGNIFICATION AND / OR BLEACHING OF A PULP |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN1166553A true CN1166553A (en) | 1997-12-03 |
Family
ID=26232649
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 97110725 Pending CN1166553A (en) | 1996-04-12 | 1997-04-11 | Process for deflingification and/or bleaching of paper pulp |
Country Status (4)
| Country | Link |
|---|---|
| EP (1) | EP0801170A1 (en) |
| JP (1) | JPH1037089A (en) |
| CN (1) | CN1166553A (en) |
| CA (1) | CA2202445A1 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100427676C (en) * | 2004-09-01 | 2008-10-22 | 曾繁寿 | Method of preparing paper pulp utilizing microwave technique |
| CN103145228A (en) * | 2013-03-06 | 2013-06-12 | 青岛大学 | Method for decoloring wastewater dyed by active dye |
| CN109736119A (en) * | 2019-02-27 | 2019-05-10 | 华南理工大学 | A kind of dioxde pulp bleaching process |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FI112958B (en) * | 1997-12-19 | 2004-02-13 | Kemira Oyj | Method for bleaching chemical pulp and use of bleaching solution |
| FR2776312B1 (en) * | 1998-03-18 | 2000-05-05 | Air Liquide | PROCESS FOR DESTRUCTION OF FLUORESCENT AGENTS CONTAINED IN OLD PAPER BY PERACETIC ACID |
| CN101265678B (en) * | 2008-04-30 | 2010-12-01 | 江西科技师范学院 | Hydrogen peroxide stabilizer composition in paper pulp bleaching |
| CA3122786A1 (en) * | 2021-06-18 | 2022-12-18 | Sixring Inc. | Temperature-controlled delignification of biomass |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| NL50696C (en) * | 1938-09-14 | |||
| FR1553704A (en) * | 1966-05-31 | 1969-01-17 | ||
| JP3046628B2 (en) * | 1991-01-23 | 2000-05-29 | 日本パーオキサイド株式会社 | Method for producing peracetic acid composition |
| BE1006057A3 (en) * | 1992-07-06 | 1994-05-03 | Solvay Interox | Method for delignification of chemical pulp. |
| RU2046869C1 (en) * | 1993-05-31 | 1995-10-27 | Акционерное общество открытого типа "Всероссийский научно-исследовательский институт целлюлозно-бумажной промышленности" | Method of bleached cellulose production |
-
1997
- 1997-04-08 EP EP97400799A patent/EP0801170A1/en not_active Withdrawn
- 1997-04-11 JP JP9415497A patent/JPH1037089A/en active Pending
- 1997-04-11 CA CA 2202445 patent/CA2202445A1/en not_active Abandoned
- 1997-04-11 CN CN 97110725 patent/CN1166553A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100427676C (en) * | 2004-09-01 | 2008-10-22 | 曾繁寿 | Method of preparing paper pulp utilizing microwave technique |
| CN103145228A (en) * | 2013-03-06 | 2013-06-12 | 青岛大学 | Method for decoloring wastewater dyed by active dye |
| CN109736119A (en) * | 2019-02-27 | 2019-05-10 | 华南理工大学 | A kind of dioxde pulp bleaching process |
| CN109736119B (en) * | 2019-02-27 | 2021-09-21 | 华南理工大学 | Paper pulp bleaching method |
Also Published As
| Publication number | Publication date |
|---|---|
| EP0801170A1 (en) | 1997-10-15 |
| JPH1037089A (en) | 1998-02-10 |
| CA2202445A1 (en) | 1997-10-12 |
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