EP0407421B1 - Procede de reduction de chlorure residuelle dans des pates feuillus - Google Patents
Procede de reduction de chlorure residuelle dans des pates feuillus Download PDFInfo
- Publication number
- EP0407421B1 EP0407421B1 EP89903748A EP89903748A EP0407421B1 EP 0407421 B1 EP0407421 B1 EP 0407421B1 EP 89903748 A EP89903748 A EP 89903748A EP 89903748 A EP89903748 A EP 89903748A EP 0407421 B1 EP0407421 B1 EP 0407421B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- pulp
- enzyme
- chlorine
- bleaching
- bleached
- 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.)
- Revoked
Links
Classifications
-
- 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
- D21C9/12—Bleaching ; Apparatus therefor with halogens or halogen-containing compounds
- D21C9/14—Bleaching ; Apparatus therefor with halogens or halogen-containing compounds with ClO2 or chlorites
-
- 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
Definitions
- the present invention concerns a method for reducing residual chlorine content in hardwood pulp that has been previously bleached using chlorine chemicals.
- Cellulose pulp obtained by sulphate cooking in particular is brown, mainly owing to lignin remaining in the pulp.
- the present understanding is that this residual lignin is linked to hemicellulose with covalent bonds. Lignin is removed by bleaching, whereby the pulp is rendered usable for high-quality paper and cardboard products.
- Bleaching is usually accomplished in a multi-stage process in which the pulp is alternately treated with oxidizing, lignin-decomposing chemicals and with chemicals dissolving the substances generated as decomposition products.
- substances containing chlorine have been used for oxidizing chemicals, such as pure chlorine gas, chlorine dioxide or sodium or potassium hypochlorite, although other types of oxidizing bleaching agents containing no chlorine are also known.
- alkali solutions have been used for extraction chemicals removing the decomposition products.
- the object of the present invention is therefore to devise a problem solution by which the residual chlorine content of bleached cellulose pulp made of hardwood can be reduced from the present level.
- the invention is characterized in that the residual chlorine content is lowered by subjecting the pulp to enzyme treatment and chlorine chemical treatment during the bleaching process, whereby said enzyme which is used is hemicellulase, cellulase, esterase or a mixture of these.
- the enzyme treatment may be carried out at an arbitrary stage of the bleaching process.
- the pulp may be treated with enzyme in connection with one of the oxidizing steps or extraction steps (alkali steps) of the process or between the respective steps, prior to said bleaching steps, or not until after said steps.
- the enzyme to be used is hemicellulase, cellulase, esterase or a mixture of these, and as suitable enzyme products may be mentioned Multi Stamm L 250 and Multi Stamm K.
- the temperature of the enzyme treatment may be in the range of 10 to 90°C, preferably 40 to 70°C, and pH within the range of 3.0 to 7.5, preferably 4.0 to 6.0.
- a further object of the invention is the use of enzyme towards reducing the residual chlorine content of bleached cellulose pulp made from hardwood.
- Suitable enzymes include hemicellulases, cellulases and esterases or mixtures of these, e.g. the enzyme products Multifect L 250 and Multifect K.
- Use of the enzyme is implemented, according to the invention, in the manner set forth in the preceding description of the bleaching procedure.
- enzyme as taught by the invention relates to reduction of the residual chlorine content in bleached cellulose pulp meant to be processed into foodstuff packaging cardboard or paper. This is because the increasingly stricter provisions regarding residual chlorine concern particularly said cardboard and paper brands, which end up as waste for disposal in waste incineration plants, where the chlorine contained in them may, when it burns, produce highly toxic dioxin.
- the enzyme-treated pulp stock batch and the reference batch were next subjected to bleaching, which took place in five consecutive oxidizing and extracting steps.
- chlorine and chlorine dioxide were used for chemicals
- sodium hydroxide in the second step sodium hydroxide
- chlorine dioxide in the third step sodium hydroxide
- sodium hydroxide in the fourth step sodium hydroxide
- chlorine dioxide in the fifth step chlorine dioxide.
- Table Ib are presented the total chlorine quantities used in bleaching, and the results of measurement found with the bleached pulp batches.
- Bleached birch sulphate pulp was used in this experiment.
- the pulp had been bleached using for bleaching chemicals in the first step chlorine (90%) and chlorine dioxide (10%), in the second step sodium hydroxide and in the third step oxygen.
- the bleached pulp was subjected to enzyme treatment under identical conditions, and using the same enzyme, as in Example 1. After treatment, the pulp was washed with water and dried at room temperature. The residual chlorine content was measured both of the enzyme-treated pulp and of the untreated, original bleached sulphate pulp, the result 1.18 being found for the former and 1.56 mg/g for the latter. Thus, the residual chlorine content of bleached pulp could be substantially lowered by means of enzyme treatment.
- the test demonstrates that the desired result is attained with the invention also in case the cellulose pulp is first bleached and treated with enzyme only thereafter.
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Wood Science & Technology (AREA)
- Paper (AREA)
- Polysaccharides And Polysaccharide Derivatives (AREA)
- Investigating Or Analysing Biological Materials (AREA)
- Hard Magnetic Materials (AREA)
- Agricultural Chemicals And Associated Chemicals (AREA)
- Chemical And Physical Treatments For Wood And The Like (AREA)
- Preparation Of Compounds By Using Micro-Organisms (AREA)
- Detergent Compositions (AREA)
Claims (8)
- Procédé de réduction de la teneur en chlore résiduel dans une pâte de feuillus qui a été préalablement décolorée par des produits chimiques à base de chlore, caractérisé en ce qu'il consiste à soumettre ladite pâte à un traitement enzymatique et à un traitement chimique au chlore au cours du processus de décoloration, et en ce que ladite enzyme utilisée est une hémicellulase, une cellulase, une estérase ou un mélange de ces enzymes.
- Procédé selon la revendication 1, caractérisé en ce qu'il consiste à soumettre la pâte à un traitement enzymatique avant ou après le traitement de décoloration.
- Procédé selon la revendication 1, caractérisé en ce que le traitement enzymatique a lieu à une température comprise entre 10 et 90° C, de préférence entre 40 et 70° C, et à un pH compris entre 3,0 et 7,5, de préférence compris entre 4, 0 et 6,0.
- Procédé selon les revendications 2 et 3, caractérisé en ce qu'on ajoute l'enzyme susceptible d'agir à la pâte non décolorée, obtenue par lessivage au sulphate d'un bois de bouleau, après quoi l'on soumet la pâte à une décoloration comprenant des étapes successives d'oxydation et d'extraction, les produits chimiques employés pour la décoloration lors des étapes d'oxydation, d'une part, étant du chlore à l'état gazeux et/ou du dioxyde de chlore, et lors des étapes d'extraction, d'autre part, étant de la soude.
- Procédé selon la revendication 4, caractérisé en ce que ladite décoloration est une décoloration au chlore en cinq étapes.
- Procédé selon les revendications 2 à 4, caractérisé en ce que la pâte obtenue par lessivage au sulphate d'un bois de bouleau est décolorée lors d'étapes successives d'oxydation et d'extraction, en ce qu'on emploie lors de la première étape du chlore à l'état gazeux et/ou du dioxyde de chlore et lors de l'étape ultérieure d'extraction, de la soude, et en ce que, après la décoloration, on ajoute l'enzyme à la pâte en suspension résultant desdites étapes, ladite enzyme pouvant agir pendant une durée choisie.
- Utilisation d'une enzyme pour réduire la teneur en chlore résiduel d'une pâte de cellulose décolorée provenant d'un bois de feuillu, ladite enzyme étant une hémicellulase, une cellulase, une estérase, ou un mélange de ces enzymes.
- Utilisation d'une enzyme selon la revendication 7 en vue de la réduction de la teneur en chlore résiduel d'une pâte de cellulose décolorée qui est destinée à être traitée chimiquement pour constituer un emballage de produits alimentaires en carton ou en papier.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FI881192A FI81395B (fi) | 1988-03-14 | 1988-03-14 | Foerfarande foer blekning av cellulosamassa. |
FI881192 | 1988-03-14 | ||
PCT/FI1989/000045 WO1989008738A1 (fr) | 1988-03-14 | 1989-03-13 | Procede de blanchiment de pate de cellulose |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0407421A1 EP0407421A1 (fr) | 1991-01-16 |
EP0407421B1 true EP0407421B1 (fr) | 1996-03-13 |
Family
ID=8526077
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP89903748A Revoked EP0407421B1 (fr) | 1988-03-14 | 1989-03-13 | Procede de reduction de chlorure residuelle dans des pates feuillus |
Country Status (12)
Country | Link |
---|---|
EP (1) | EP0407421B1 (fr) |
JP (1) | JPH03505758A (fr) |
AT (1) | ATE135429T1 (fr) |
AU (1) | AU626846B2 (fr) |
BR (1) | BR8907314A (fr) |
CA (1) | CA1334581C (fr) |
DE (1) | DE68925967T2 (fr) |
DK (1) | DK175185B1 (fr) |
FI (1) | FI81395B (fr) |
NO (1) | NO174722C (fr) |
NZ (1) | NZ228308A (fr) |
WO (1) | WO1989008738A1 (fr) |
Families Citing this family (21)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5298405A (en) * | 1986-04-30 | 1994-03-29 | Alko Limited | Enzyme preparations with recombinantly-altered cellulose profiles and methods for their production |
FI90888B (fi) * | 1989-02-14 | 1993-12-31 | Enso Gutzeit Oy | Menetelmä selluloosamassan valkaisemiseksi |
FI86896B (fi) * | 1989-05-04 | 1992-07-15 | Enso Gutzeit Oy | Foerfarande foer blekning av cellulosamassa. |
DK420289D0 (da) * | 1989-08-25 | 1989-08-25 | Novo Nordisk As | Fremgangsmaade til behandling af lignocellulosepulp |
NZ235679A (en) * | 1989-10-18 | 1993-01-27 | Int Paper Co | Bleaching lignocellulosic pulp using (a) treatment with xylanase and (b) one or more chemical bleaching stages |
SE465320B (sv) * | 1990-01-10 | 1991-08-26 | Korsnaes Ab | Preparat som uppvisar enzymatisk delignifieringsaktivitet, saett att framstaella detsamma och tillaempningar daerav |
FI88315C (fi) * | 1990-04-04 | 1993-04-26 | Enso Gutzeit Oy | Foerfarande foer blekning av cellulosamassa |
US5837515A (en) * | 1990-05-16 | 1998-11-17 | Alko-Yhtiot Oy | Enzyme preparations and methods for their production |
GB9018426D0 (en) * | 1990-08-22 | 1990-10-03 | Sandoz Ltd | Improvements in or relating to novel compounds |
NZ239500A (en) * | 1990-08-24 | 1993-08-26 | Novo Nordisk As | Xylanases obtained from bacillus pumilus and use in a lignocellulosic chemical pulping process |
DE4129739A1 (de) * | 1990-09-11 | 1992-03-12 | Sandoz Ag | Chlorfreies bleichen von papierpulpe |
FI108800B (fi) * | 1991-05-07 | 2002-03-28 | Iogen Corp | Menetelmä ja laitteisto entsyymin käyttämiseksi paperimassan valmistuksessa ja valkaisussa |
US5498534A (en) * | 1992-03-25 | 1996-03-12 | The United States Of America As Represented By The Secretary Of Agriculture | Method of removing color from wood pulp using xylanase from streptomyces roseiscleroticus NRRL B-11019 |
US5369024A (en) * | 1992-03-25 | 1994-11-29 | The United States Of America As Represented By The Secretary Of Agriculture | Xylanase from streptomyces roseiscleroticus NRRL-11019 for removing color from kraft wood pulps |
US5935836A (en) * | 1994-07-29 | 1999-08-10 | Rohm Enzyme Finland Oy | Actinomadura xylanase sequences and methods of use |
US6300114B1 (en) | 1994-07-29 | 2001-10-09 | Rohm Enzyme Finland Oy | Sequences of xylanase and xylanase expression vectors |
US5871730A (en) * | 1994-07-29 | 1999-02-16 | Universite De Sherbrooke | Thermostable xylanase DNA, protein and methods of use |
US7816129B2 (en) | 1994-07-29 | 2010-10-19 | Ab Enzymes Gmbh | Production and secretion of proteins of bacterial origin in filamentous fungi |
AU2002229430A1 (en) | 2001-01-18 | 2002-07-30 | Iogen Bio-Products Corporation | Use of xylanase in pulp bleaching |
WO2003074780A1 (fr) * | 2002-03-06 | 2003-09-12 | Iogen Bio-Products Corporation | Traitement de pate chimique par des xylanases |
CN104963206A (zh) * | 2014-12-11 | 2015-10-07 | 华东理工常熟研究院有限公司 | 酶改性纸浆纤维、木塑复合材料及其制备方法 |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NZ216726A (en) * | 1985-07-15 | 1990-08-28 | Repligen Corp | Use of lignin-degrading enzymes from phanerochaete chrysosporium for treatment of wood pulp and e1 effluent |
ZA894239B (en) * | 1988-06-08 | 1990-03-28 | Int Paper Co | Enzymatic delignification of lignocellulosic material |
DE68914112T2 (de) * | 1988-11-23 | 1994-08-04 | Sandoz Ag | Benutzung von Enzymen von Aureobasidium Pullulans für das Bleichen von Zellstoff. |
-
1988
- 1988-03-14 FI FI881192A patent/FI81395B/fi not_active Application Discontinuation
-
1989
- 1989-03-13 EP EP89903748A patent/EP0407421B1/fr not_active Revoked
- 1989-03-13 BR BR898907314A patent/BR8907314A/pt not_active IP Right Cessation
- 1989-03-13 NZ NZ228308A patent/NZ228308A/xx unknown
- 1989-03-13 AU AU32923/89A patent/AU626846B2/en not_active Ceased
- 1989-03-13 JP JP1502856A patent/JPH03505758A/ja active Pending
- 1989-03-13 DE DE68925967T patent/DE68925967T2/de not_active Revoked
- 1989-03-13 CA CA000593523A patent/CA1334581C/fr not_active Expired - Lifetime
- 1989-03-13 WO PCT/FI1989/000045 patent/WO1989008738A1/fr not_active Application Discontinuation
- 1989-03-13 AT AT89903748T patent/ATE135429T1/de active
-
1990
- 1990-09-04 DK DK199002119A patent/DK175185B1/da not_active IP Right Cessation
- 1990-09-07 NO NO903913A patent/NO174722C/no not_active IP Right Cessation
Non-Patent Citations (2)
Title |
---|
Chauvet, J-M et al, "Assistance in bleaching of never-dried pulps by the use of xylanases, consequenses on pulp properties", Fourth International Symposium on Wood and Pulping Chemistry, April 27-30, 1987, Paris-Palais des Congrès, pages 325-327. * |
M.G. Paice et al: "Viscosity-Enhancing Bleaching of Hardwood Kraft Pulp with Xylanase from a Cloned Gene", Biotechnology and Bioengineering, Vol. 32, July 1988, pages 235-239. * |
Also Published As
Publication number | Publication date |
---|---|
DK211990D0 (da) | 1990-09-04 |
NO903913L (no) | 1990-09-07 |
DE68925967D1 (de) | 1996-04-18 |
DK211990A (da) | 1990-11-07 |
NO903913D0 (no) | 1990-09-07 |
FI81395B (fi) | 1990-06-29 |
FI881192A0 (fi) | 1988-03-14 |
AU626846B2 (en) | 1992-08-13 |
WO1989008738A1 (fr) | 1989-09-21 |
DE68925967T2 (de) | 1996-09-12 |
EP0407421A1 (fr) | 1991-01-16 |
NO174722C (no) | 1994-06-22 |
ATE135429T1 (de) | 1996-03-15 |
BR8907314A (pt) | 1991-03-19 |
DK175185B1 (da) | 2004-06-28 |
NO174722B (no) | 1994-03-14 |
NZ228308A (en) | 1990-06-26 |
FI881192A (fi) | 1989-09-15 |
CA1334581C (fr) | 1995-02-28 |
AU3292389A (en) | 1989-10-05 |
JPH03505758A (ja) | 1991-12-12 |
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