EP0165867B1 - Verfahren zum Bleichen von mechanischer Pulpe mittels Wasserstoffperoxid - Google Patents

Verfahren zum Bleichen von mechanischer Pulpe mittels Wasserstoffperoxid Download PDF

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Publication number
EP0165867B1
EP0165867B1 EP85401182A EP85401182A EP0165867B1 EP 0165867 B1 EP0165867 B1 EP 0165867B1 EP 85401182 A EP85401182 A EP 85401182A EP 85401182 A EP85401182 A EP 85401182A EP 0165867 B1 EP0165867 B1 EP 0165867B1
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EP
European Patent Office
Prior art keywords
hydrogen peroxide
oxygen
bleaching
pulp
mechanical pulp
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.)
Expired
Application number
EP85401182A
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English (en)
French (fr)
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EP0165867A1 (de
Inventor
Dominique Lachenal
Claude Bourne
Christian De Choudens
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
Original Assignee
LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
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First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=9305255&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0165867(B1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude filed Critical LAir Liquide SA pour lEtude et lExploitation des Procedes Georges Claude
Priority to AT85401182T priority Critical patent/ATE31333T1/de
Publication of EP0165867A1 publication Critical patent/EP0165867A1/de
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Publication of EP0165867B1 publication Critical patent/EP0165867B1/de
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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
    • D21C9/16—Bleaching ; Apparatus therefor with per compounds
    • D21C9/163—Bleaching ; Apparatus therefor with per compounds with peroxides
    • 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
    • D21C9/1057—Multistage, with compounds cited in more than one sub-group D21C9/10, D21C9/12, D21C9/16

Definitions

  • the invention relates to a process for bleaching mechanical pulp with hydrogen peroxide.
  • the bleaching of a mechanical paper pulp consists in eliminating the colored groups from the pulp by oxidation or by reduction of these groups, without dissolving the constituents of the wood in the bleaching liquor. This operation is carried out industrially with hydrogen peroxide H 2 0 2 (P) or sodium or zinc hydrosulfite.
  • the use of hydrogen peroxide (P) makes it possible to reach whiteness levels higher than those obtained with h y drosulfite. It has therefore become widespread, where the objective is to prepare whiteness 80 pasta (ISO standard).
  • the bleaching is carried out either in a single stage with hydrogen peroxide, or in two stages, the first stage being a treatment with hydrogen peroxide and the second a treatment with hydrosulfite.
  • the medium is made alkaline by the addition of caustic soda.
  • the hydrogen peroxide rapidly decomposes into oxygen with transient formation of radical species ineffective in the bleaching process. This decomposition is catalyzed by the cations of transition metals present in the pulp.
  • bleaching chemical pulps consists in dissolving the residual lignin (delignification), in order to obtain cellulosic pulps free of lignin. It is therefore no longer a question of carrying out a moderate treatment on the colored groups of the paste, but of depolymerizing and dissolving the macromolecules carrying these colored groups.
  • oxygen is used to dissolve the lignin from the plant in order to obtain a chemical paste.
  • oxygen is not a bleaching agent for mechanical pulps.
  • DH ANDREWS AND RP SINGH indicate in the work entitled “The bleaching of pulp", editor TAPPI Press (1979), page 215, that oxygen in an alkaline medium causes yellowing of the mechanical pulp, which is consistent with what is known about the chemistry of lignin in the presence of oxygen.
  • oxygen is capable of enhancing the whitening action of hydrogen peroxide in the bleaching of mechanical pulps, whether the two reagents are used in sequence or simultaneously.
  • the process for bleaching mechanical pulp with hydrogen peroxide according to the invention is characterized in that, before or simultaneously to said peroxide treatment, the mechanical pulp is subjected to an oxygen pressure greater than or equal to atmospheric pressure.
  • oxygen pressure is meant both the use of oxygen at atmospheric pressure and under pressure, the latter being able to reach a few bars.
  • the action of oxygen can therefore be exerted, either from atmospheric oxygen which then acts on the dough, in particular by sweeping or licking, or from oxygen under pressure, for example that exerted under the effect the height of a column of dough in an ascending whitening tower.
  • oxygen can be used as a bleaching agent since, as we saw in the preamble, oxygen used alone in an alkaline medium has no bleaching action on a mechanical pulp.
  • the mechanical pulp is bleached with hydrogen peroxide under the usual industrial conditions, that is to say in an alkaline medium in the presence of stabilizing agents which can be sodium silicate, magnesium sulphate, the complexes usually used such as the sodium salts of diethylenetriaminopentacetic acid, at a temperature below 100 ° C. under an oxygen atmosphere.
  • stabilizing agents which can be sodium silicate, magnesium sulphate, the complexes usually used such as the sodium salts of diethylenetriaminopentacetic acid, at a temperature below 100 ° C. under an oxygen atmosphere.
  • the mechanical pulp containing the bleaching agents can be mixed with gaseous oxygen in a suitable mixer before being sent to the bleaching tower, preferably upward.
  • the pulp containing bleaching products is sent to an oxygen-containing tower or to any other type of reactor containing oxygen and where the bleaching of the pulp will take place or will continue. It is therefore a process which will be called P / O (sequence: peroxide hydrogen / oxygen) according to the usual internationally accepted codification.
  • the mechanical pulp made alkaline by the addition of sodium hydroxide or silicate is mixed with oxygen, then left under oxygen pressure at a temperature below 100 ° C. for the necessary time, which should not exceed four hours.
  • This operation is carried out in a suitable reactor which can be a tower.
  • the actual bleaching reagents are then added, in particular hydrogen peroxide.
  • the dough is placed under the usual bleaching conditions with hydrogen peroxide. This process will therefore be referenced O P according to the accepted codification.
  • test No. 1 the pulp is bleached in a single stage with an alkaline liquor of hydrogen peroxide under the following conditions (the reactant levels being expressed by weight of pure product relative to the weight of pulp counted in dry):
  • the paste and the alkaline liquor are introduced into an enclosure at the processing temperature. After this treatment, the dough is washed. Its whiteness is 72.2%. The consumption of hydrogen peroxide is 1.75%.
  • This test No. 1 corresponds to the sequence P.
  • test No. 2 the same unbleached mechanical pulp is treated with oxygen under the following conditions:
  • This test No. 2 therefore corresponds to the OP sequence.
  • test No. 4 The whiteness obtained after this P / O treatment is 72.3%, a gain of 1.7 points compared to test No. 3, in which no oxygen was introduced.
  • test No. 6 The same test is then repeated, this time subjecting the paste to a pressure of 2 bars throughout the treatment with hydrogen peroxide (test No. 6). After this P / O treatment, the whiteness obtained is 75.2%, a gain of 1.2 points compared to test no. 5 which does not include oxygen.
  • the reference 1 designates the paste which is sent to the mixer 2 where it simultaneously receives oxygen 3 and hydrogen peroxide 4 brought into the mixer 2 by the three-way valve 5.
  • the pasty mixture produced is sent through line 6 to reach the rising tower 7 where this mixture of paste and reagents remains for the time necessary for the reaction.
  • the bleached dough is collected in 8.
  • the height of the column of dough in tower 7 ensures sufficient oxygen pressure.
  • the method according to the invention can be used successfully for bleaching mechanical pulps.

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  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Wood Science & Technology (AREA)
  • Paper (AREA)
  • Detergent Compositions (AREA)

Claims (6)

1. Verfahren zum Bleichen von mechanischer Pulpe mittels Wasserstoffperoxid, dadurch gekennzeichnet, dass man vor oder gleichzeitig mit der Peroxidbehandlung die mechanische Pulpe einem Sauerstoffdruck höher als oder gleich wie derAmtosphärendruck unterzieht.
2. Verfahren nach Anspruch 1, dadurch gekennzeichnet, dass der Sauerstoffdruck unter 5 bar und vorzugsweise zwischen 2 und 3 bar liegt.
3. Verfahren nach einem der Ansprüche 1 oder 2, dadurch gekennzeichnet, dass, wenn der Sauerstoffdruck aufgebracht wird, der pH der Pulpe zwischen 9 und 12 und vorzugsweise zwischen 10 und 11 liegt.
4. Verfahren nach einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, dass, wenn der Sauerstoffdruck aufgebracht wird, die Temperatur zwischen 40 und 100°C, vorzugsweise zwischen 50 und 70°C liegt.
5. Verfahren nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, dass die Konsistenz der behandelten mechanischen Pulpe zwischen 8 und 30% und vorzugsweise zwischen 10 und 20% liegt.
6. Verfahren nach einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, dass die Wasserstoffperoxidbleichflüssigkeit eine übliche Flüssigkeit ist, die ausser Wasserstoffperoxid Soda, Natriumsilikat und übliche Komplexbildner enthält.
EP85401182A 1984-06-15 1985-06-14 Verfahren zum Bleichen von mechanischer Pulpe mittels Wasserstoffperoxid Expired EP0165867B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT85401182T ATE31333T1 (de) 1984-06-15 1985-06-14 Verfahren zum bleichen von mechanischer pulpe mittels wasserstoffperoxid.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8409718A FR2566015B1 (fr) 1984-06-15 1984-06-15 Procede de blanchiment de pate mecanique par le peroxyde d'hydrogene
FR8409718 1984-06-15

Publications (2)

Publication Number Publication Date
EP0165867A1 EP0165867A1 (de) 1985-12-27
EP0165867B1 true EP0165867B1 (de) 1987-12-09

Family

ID=9305255

Family Applications (1)

Application Number Title Priority Date Filing Date
EP85401182A Expired EP0165867B1 (de) 1984-06-15 1985-06-14 Verfahren zum Bleichen von mechanischer Pulpe mittels Wasserstoffperoxid

Country Status (7)

Country Link
US (1) US4756798A (de)
EP (1) EP0165867B1 (de)
JP (1) JP2504400B2 (de)
AT (1) ATE31333T1 (de)
CA (1) CA1259454A (de)
DE (1) DE3561165D1 (de)
FR (1) FR2566015B1 (de)

Families Citing this family (24)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ES2004389A6 (es) * 1986-03-21 1989-01-01 Air Prod & Chem Un metodo mejorado de deslignificacion y blanqueo secuenciales de pasta de papel lignocelulosica
US5011572A (en) * 1989-05-19 1991-04-30 Fmc Corporation Two stage process for the oxygen delignification of lignocellulosic fibers with peroxide reinforcement in the first stage
US5607546A (en) * 1990-02-13 1997-03-04 Molnlycke Ab CTMP-process
SE466060C (sv) 1990-02-13 1995-09-11 Moelnlycke Ab Absorberande kemitermomekanisk massa och framställning därav
AU642971B2 (en) * 1990-02-19 1993-11-04 Paper Australia Pty Ltd Bleaching of paper pulp
NZ237019A (en) * 1990-02-19 1992-11-25 Amcor Ltd Bleaching paper pulp by initially treating with oxygen and/or hydrogen peroxide and subsequently treating with a bleaching agent without intervening washing steps
BE1004674A3 (fr) * 1991-03-11 1993-01-12 Interox Internat Sa Procede pour le blanchiment d'une pate a papier chimique et application de ce procede au blanchiment d'une pate kraft.
CA2082557C (en) * 1992-02-24 1997-03-11 Charles W. Hankins Integrated pulping process of waste paper yielding tissue-grade paper fibers
SE500616C2 (sv) * 1993-06-08 1994-07-25 Kvaerner Pulping Tech Blekning av kemisk massa med peroxid vid övertryck
US6149766A (en) * 1993-06-08 2000-11-21 Kvaerner Pulping Technologies, A/B Process for peroxide bleaching of chemical pulp in a pressurized bleaching vessel
CA2157154A1 (en) * 1994-08-29 1996-03-01 Gordon Leary Bleaching of high-yield pulps with oxygen
DE69608910T2 (de) * 1995-12-07 2001-01-18 Beloit Technologies, Inc. Delignifizierung eines papierzellstoffs mittlerer konsistenz mittels sauerstoff
DE19626200C2 (de) * 1996-06-29 2001-02-01 Voith Sulzer Stoffaufbereitung Verfahren zur Erhöhung des Weißgrades von Altpapierfaserstoff
GB0004988D0 (en) 2000-03-01 2000-04-19 Unilever Plc Composition and method for bleaching a substrate
US6899790B2 (en) 2000-03-06 2005-05-31 Georgia-Pacific Corporation Method of providing papermaking fibers with durable curl
US6627041B2 (en) 2000-03-06 2003-09-30 Georgia-Pacific Corporation Method of bleaching and providing papermaking fibers with durable curl
US7297225B2 (en) * 2004-06-22 2007-11-20 Georgia-Pacific Consumer Products Lp Process for high temperature peroxide bleaching of pulp with cool discharge
US8138106B2 (en) 2005-09-30 2012-03-20 Rayonier Trs Holdings Inc. Cellulosic fibers with odor control characteristics
US20080087390A1 (en) * 2006-10-11 2008-04-17 Fort James Corporation Multi-step pulp bleaching
US8845860B2 (en) 2010-09-16 2014-09-30 Georgia-Pacific Consumer Products Lp High brightness pulps from lignin rich waste papers
TW201610265A (zh) 2014-05-20 2016-03-16 喬治亞太平洋消費者產品公司 非木材纖維之漂白及植物性雜質減量方法
TW201610261A (zh) 2014-05-20 2016-03-16 喬治亞太平洋消費者產品公司 非木材纖維之漂白及植物性雜質減量方法
TW201544652A (zh) * 2014-05-20 2015-12-01 Georgia Pacific Consumer Prod 非木材纖維之漂白及植物性雜質減量方法
CN108642943B (zh) * 2018-04-03 2021-03-19 中国林业科学研究院林产化学工业研究所 一种制备高白度高强度桉木化学机械浆的方法

Family Cites Families (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA632280A (en) * 1958-07-02 1961-12-05 Kimberly-Clark Corporation Manufacture of bleached cellulosic products resistant to brightness reversion
FI45574C (fi) * 1970-05-11 1972-07-10 Kymin Oy Kymmene Ab Menetelmä selluloosapitoisten aineiden valkaisemiseksi.
US3719552A (en) * 1971-06-18 1973-03-06 American Cyanamid Co Bleaching of lignocellulosic materials with oxygen in the presence of a peroxide
US4029543A (en) * 1971-12-14 1977-06-14 Mo Och Domsjo Mechanically freeing wood fibers in the presence of spent peroxide bleaching liquor
US3832276A (en) * 1973-03-07 1974-08-27 Int Paper Co Delignification and bleaching of a cellulose pulp slurry with oxygen
SE7502060L (sv) * 1975-02-24 1976-08-25 Alf Sa Sett vid framstellning av mekanisk pappersmassa
US4372812A (en) * 1978-04-07 1983-02-08 International Paper Company Chlorine free process for bleaching lignocellulosic pulp
US4410397A (en) * 1978-04-07 1983-10-18 International Paper Company Delignification and bleaching process and solution for lignocellulosic pulp with peroxide in the presence of metal additives
US4239643A (en) * 1979-01-02 1980-12-16 Monsanto Company Peroxide stabilization
FR2457339A1 (fr) * 1979-05-25 1980-12-19 Interox Procede pour la delignification et le blanchiment de pates cellulosiques chimiques et semi-chimiques
JPS59137591A (ja) * 1983-01-28 1984-08-07 王子製紙株式会社 リグノセルロ−ス物質の漂白方法
JPS59179892A (ja) * 1983-03-25 1984-10-12 王子製紙株式会社 リグノセルロ−ス物質の漂白方法
DE3428352A1 (de) * 1984-08-01 1986-02-13 Degussa Ag, 6000 Frankfurt Verfahren zur delignifizierung und bleiche von zellstoffen
US4568420B1 (en) * 1984-12-03 1999-03-02 Int Paper Co Multi-stage bleaching process including an enhanced oxidative extraction stage

Also Published As

Publication number Publication date
FR2566015B1 (fr) 1986-08-29
EP0165867A1 (de) 1985-12-27
JP2504400B2 (ja) 1996-06-05
ATE31333T1 (de) 1987-12-15
US4756798A (en) 1988-07-12
DE3561165D1 (en) 1988-01-21
CA1259454A (fr) 1989-09-19
FR2566015A1 (fr) 1985-12-20
JPS6112994A (ja) 1986-01-21

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