WO2005118950A1 - Procede de production d'une pate chimique - Google Patents

Procede de production d'une pate chimique Download PDF

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Publication number
WO2005118950A1
WO2005118950A1 PCT/AT2005/000171 AT2005000171W WO2005118950A1 WO 2005118950 A1 WO2005118950 A1 WO 2005118950A1 AT 2005000171 W AT2005000171 W AT 2005000171W WO 2005118950 A1 WO2005118950 A1 WO 2005118950A1
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WO
WIPO (PCT)
Prior art keywords
pulp
cellulose
weight
content
alkali
Prior art date
Application number
PCT/AT2005/000171
Other languages
German (de)
English (en)
Inventor
Herbert Sixta
Original Assignee
Lenzing Aktiengesellschaft
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Lenzing Aktiengesellschaft filed Critical Lenzing Aktiengesellschaft
Priority to CA2568594A priority Critical patent/CA2568594C/fr
Priority to EP05741840.2A priority patent/EP1753908B1/fr
Publication of WO2005118950A1 publication Critical patent/WO2005118950A1/fr
Priority to NO20065354A priority patent/NO338462B1/no

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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
    • D21C9/001—Modification of pulp properties
    • D21C9/002—Modification of pulp properties by chemical means; preparation of dewatered pulp, e.g. in sheet or bulk form, containing special additives
    • D21C9/004—Modification of pulp properties by chemical means; preparation of dewatered pulp, e.g. in sheet or bulk form, containing special additives inorganic compounds
    • 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
    • D21C11/00—Regeneration of pulp liquors or effluent waste waters
    • D21C11/0007—Recovery of by-products, i.e. compounds other than those necessary for pulping, for multiple uses or not otherwise provided for
    • 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
    • D21C3/00—Pulping cellulose-containing materials
    • D21C3/04—Pulping cellulose-containing materials with acids, acid salts or acid anhydrides
    • D21C3/06—Pulping cellulose-containing materials with acids, acid salts or acid anhydrides sulfur dioxide; sulfurous acid; bisulfites sulfites
    • 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

Definitions

  • the present invention relates to a method for producing a chemical pulp according to the preamble of patent claim 1.
  • the production of chemical pulps is now dominated by the acidic bisulfite digestion process and the pre-hydrolysis-Kraft process.
  • the acidic bisulfite digestion process is a very environmentally friendly technology due to the high yield and the good opportunities to utilize by-products and waste products or to use them for energy.
  • the known cleaning steps include the removal of non-cellulosic material, e.g. of extract substances, lignins and hemicelluloses, as well as the change in the molecular weight distribution towards a narrow, monomodal distribution with a minimum of low-molecular carbohydrates.
  • Alkaline extraction is usually used to remove short-chain carbohydrates from wood pulp and to produce highly reactive chemical pulps.
  • the pulp is treated with lye and then squeezed out.
  • cold alkali extraction CCE
  • hot alkali extraction HCE
  • the present invention has for its object to provide an improved process for the production of chemical pulps, in which the disadvantages described above when performing a cold and / or
  • Hot alkali extraction step can be avoided.
  • At least one alkaline extraction step in which the pulp is treated with lye and then pressed off
  • beta-cellulose is understood by the person skilled in the art to mean that portion in a cellulosic material which (in contrast to alpha-cellulose) is soluble in a 17.5% solution of NaOH at 20 ° C., but when the solution is acidified (in contrast to gamma cellulose) with 4.75M H 2 SO 4 fails again. It has now been found that a return of the alkali resulting from the pressing of the pulp to the alkaline treatment of the pulp and thus a significant reduction in the amount of fresh liquor required can be achieved if the content of beta-cellulose in the press liquor is reduced. Obviously, an increased content of beta-cellulose in the recycled alkali leads to a deterioration in the result of the alkali extraction. Surprisingly, it was found that, on the other hand, the content of gamma cellulose is less important in this context.
  • At least part of the recycled alkali is preferably treated by means of a membrane separation process.
  • the membrane separation process is preferably a nano or an ultrafiltration process.
  • membranes with a cut-off of ⁇ 2000 g / mol, in particular ⁇ 1000 g / mol are preferably used to carry out nanofiltration.
  • the ratio between retentate and permeate is set between 2 and 5, preferably between 4 and 5.
  • membranes with a cut-off of ⁇ 50,000 g / mol, in particular ⁇ 20,000 g / mol. This means that 100% of the beta cellulose and more than 10% of the gamma cellulose, preferably more than 30%, can be removed.
  • the ratio between retentate and permeate is set between 2 and 5, preferably between 4 and 5.
  • All or part of the permeate from the membrane separation process can be fed to the liquor tank, from which the liquor used to treat the pulp is removed.
  • beta-cellulose Another possibility for reducing the content of beta-cellulose is that at least part of the recycled alkali is treated thermally. That part of beta-cellulose, which (such as xylan) has no branched structures, is broken down into gamma-cellulose.
  • the thermal treatment is preferably carried out at a temperature of more than 50 ° C., preferably more than 70 ° C., for a period of 10 minutes to 300 minutes, preferably 30 minutes.
  • the press liquor is preferably treated both by means of a membrane separation process and thermally.
  • the press liquor can be pre-cleaned using a filter to remove undissolved particles.
  • a preferred embodiment of the process according to the invention is characterized in that the extraction step is a cold alkali extraction in which the treatment of the pulp with lye is carried out at a temperature of less than 50 ° C., preferably less than 25 ° C.
  • the treatment of the pulp with lye is preferably carried out at a consistency of more than 5% by weight, preferably 10% by weight> cellulose (based on the mass of the entire suspension), and at a concentration of the lye of more than 5% by weight. %, preferably 9% by weight (based on the mass of the solution).
  • a particularly interesting embodiment of a cold alkali extraction consists in that during the treatment of the pulp with the lye the consistency is brought to more than 10% by weight, preferably more than 30% by weight of cellulose, a lye content of less than 7% by weight. > Based on the solution is set and the solution is cooled to temperatures of less than -10 ° C, preferably -15 ° C to -20 ° C. This method is referred to below as "freeze purification".
  • This method is based on the phenomenon that water crystallizes out of the alkali lye when it freezes, which means that the remaining lye is more concentrated. As a result, the concentration of lye can be significantly reduced without impairing the cleaning effect.
  • a further preferred embodiment of the method according to the invention is characterized in that the extraction step is a hot alkali extraction in which the treatment of the pulp with lye is carried out at a temperature of more than 80 ° C, preferably 110 ° C.
  • the treatment of the pulp with lye is preferably carried out at a consistency of more than 5% by weight, preferably 10% by weight of cellulose (based on the mass of the entire suspension), and at a concentration of the lye of more than 3% by weight. , preferably more than 5% by weight (based on solution).
  • a particularly preferred embodiment of the method according to the invention is characterized in that the pulp is subjected to both a cold alkali extraction and a hot alkali extraction. This is particularly advantageous when processing pulps from an acidic bisulfite digestion.
  • washing steps or bleaching treatments can be carried out.
  • the amount of beta-cellulose in the alkali used to treat the pulp is less than 20 g / 1, preferably less than 5 g / 1 Liquor (ie liquor plus water contained in the pulp) is.
  • the gamma-cellulose content in the liquor used for the treatment of the pulp is advantageously less than 40 g / 1, preferably less than 20 g / 1 liquor.
  • the process according to the invention can be carried out advantageously in particular if an acid bisulfite process is used as the digestion process.
  • the present invention also relates to the use of a chemical pulp produced by the process according to the invention as a starting material for the production of lyocell moldings, cellulose acetate moldings and cellulose ethers.
  • “Lyocell shaped bodies” are to be understood as meaning cellulosic shaped bodies which are produced by the so-called amine oxide process, i.e. by dissolving pulp in an aqueous solution of a tertiary amine oxide, shaping the solution and precipitating from the shaped solution.
  • the pulp produced according to the invention should preferably have a viscosity of 350-550 ml / g, preferably 350-450 ml / g, a pentosan content of less than 2% by weight, preferably less than 1% by weight. % o, and have an R18 content of more than 94% by weight, preferably more than 95% by weight.
  • R 18 content as the residue that can be filtered off after treatment with 18% strength alkali (according to DIN 54355).
  • pulps which have been obtained by means of an acid bisulfite digestion and which have been purified by means of at least one cold and one hot alkali extraction give excellent values with regard to the strength properties of lyocell fibers produced therefrom.
  • Lyocell moldings produced in this way are characterized in particular by a significantly lower proportion of hemicelluloses.
  • the content of pentosan in the lyocell moldings according to the invention is preferably 1.5% by weight and less, particularly preferably 1% by weight and less.
  • the strength properties of Lyocell fibers produced in this way are in the same range as those of fibers from a pre-hydrolysis kraft pulp. This was previously not possible when using a pulp derived from an acidic bisulfite process. If the pulp produced according to the invention is used for the production of cellulose acetate moldings, it should preferably have a viscosity of more than 450 ml / g, preferably 500-600 ml / g, a pentosan content of less than 2% by weight, preferably less than 1% by weight. %, and an Rl 8 content of more than 95% by weight, preferably more than 96% by weight.
  • the pulp produced according to the invention is used for the production of cellulose ethers, in particular for the production of methyl cellulose, hydroxypropylmethyl cellulose and hydroxyethyl cellulose, it should preferably have a viscosity of 230-300 ml / g, preferably 250 ml / g, a pentosan content of less than 2% by weight. %, preferably less than 1% by weight, and an Rl 8 content of more than 94% by weight, preferably more than 95% by weight.
  • pulps from an acidic bisulfite digestion which were cleaned by means of both a cold alkali extraction and a hot alkali extraction without washing step between the two extraction steps (in this case, the remaining alkali from the cold alkali extraction serves as the alkali source in hot alkali extraction), ideal for the production of high-purity, low-molecular cellulose ethers.
  • FIG. 1 schematically shows a preferred embodiment of the method according to the invention using a cold alkali extraction.
  • Figure 2 shows the influence of the content of beta-cellulose and gamma-cellulose in the alkali used for alkali extraction on the residual pentosan content of a purified pulp.
  • an unbleached, washed pulp 1 obtained from hardwood by means of an acid bisulphite digestion is pressed in a press 2 to a consistency of more than 30% by weight, preferably 35% by weight.
  • the viscosity of the pulp is, for example, from 220 to 550 ml / g if it is to be used for the production of lyocell moldings or for the production of low-molecular, high-purity cellulose ethers, or 500 to 800 ml / g if it is used for the production of cellulose acetate should.
  • the squeezed liquid 3 which contains organic and inorganic substances from the spent sulfite liquor, is returned to the recovery circuit.
  • the press cake 4 after having been thinned to a consistency of approximately 5 to 15% by weight, preferably 10% by weight, with starchy press liquor, enters the cold-alkali cleaning station 5 (CCE tank).
  • the aqueous alkaline pulp suspension is thoroughly mixed in the CCE tank 5 with residence times of 10 to 120 min, preferably 50 min, and temperatures of 10 to 50 ° C, preferably 25 ° C.
  • the pulp suspension 6 treated in this way is then fed to the second press 7, in which the alkali-soluble short-chain carbohydrates are separated from the solid phase.
  • the cellulose consistency after pressing should be between 30 to 40% by weight, preferably 35% by weight.
  • the press cake 8 is scraped off, diluted to a lower consistency and fed to further process steps.
  • Such further process steps include, for example, a hot alkali extraction (with or without a washing step between the two alkali extraction steps), oxygen delignification and / or chlorine dioxide treatment and, if appropriate, bleaching treatments.
  • Part of the press liquor 9 is passed over a filter 10 in order to remove fibers and undissolved particles, and then treated in a membrane separation process by means of, for example, an ultra or nanofiltration device 11.
  • part of the press liquor 23 can be returned directly to the CCE tank 5.
  • the pressure operated membrane separation system removes the dissolved polymeric and oligomeric carbohydrate breakdown products.
  • the efficiency of the removal depends on the cut-off of the membrane system used. In the case of nanofiltration with cut-offs of ⁇ 1000 g / mol, significant fractions of gamma-cellulose are retained.
  • the permeate 12 (with a content of beta-cellulose of 0 g / 1 and a content of gamma-cellulose of ⁇ 30 g / 1) is returned via line 16 to the dewatered pulp in the CCE tank 5, it is made up by means of make -Up liquor 15 in a separate tank 14 (or alternatively in-line) strengthened.
  • This closed cycle enables the recovery of a considerable part of the alkali required for the cold alkali extraction.
  • the ratio between retentate and permeate is preferably kept between 2 and 5, in particular between 4 and 5. In the latter case, 80-83% NaOH recovery in the permeate can be achieved.
  • the retentate 13 with a hemicellulose content of more than 100 g / l is pumped to a mixing tank 16, in which reagents 17, e.g. surface-active substances and / or polyelectrolytes, are added in order to precipitate the high molecular weight fraction (beta-cellulose).
  • the phase separation can be completed in a sedimentation tank 18 or by other suitable measures (not shown here, e.g. microfiltration etc.).
  • the precipitate 19, which is characterized as a high molecular weight hemicellulose fraction (beta-cellulose), can be further purified to give different degrees of purity.
  • the beta-cellulose-free supernatant 20 can either be returned to the alkali extraction tank or used as a source of gamma-cellulose 21.
  • the proportion of beta-cellulose can be reduced by a thermal treatment 22 of the press liquor. With a thermal treatment of 30 minutes at 90 ° C, a 50% conversion of beta-cellulose to gamma-cellulose was observed.
  • Pulp was subjected to cold alkali extraction, with fresh liquor, a liquor containing 20 g / 1 gamma cellulose and a liquor containing 14 g / 1 beta cellulose and 24 g / 1 gamma cellulose, each in different concentrations were used.
  • the pentosan content of the treated pulp was determined.
  • Figure 2 shows the influence of the respective proportions of dissolved beta and gamma cellulose on the residual content of pentosan in the pulp.
  • UABD pulp An unbleached beech pulp (UBABD pulp) obtained by means of an acid bisulfite digestion was dewatered to a consistency of 35% by weight according to the method described with reference to FIG. 1 and a cold alkali extraction (100 g / 1 NaOH, 25 ° C., residence time 30 min).
  • the chemical properties of the starting pulp are described in the following table:
  • the alkaline pulp suspension was pressed to a consistency of 32% by weight.
  • the use of nanofiltration to reduce the content of beta-cellulose can significantly reduce the amount of fresh lye (NaOH make-up) required.
  • the necessary amount of fresh liquor can even increase by 409 kg NaOH / t otro pulp in the case of a target concentration of ⁇ 1 g / 1 beta-cellulose (example 3 c compared to example 3 a) or by 276 kg NaOH / t otro cellulose in the case of a target concentration of ⁇ 5 g / 1 beta cellulose (example 3f compared to example 3d) are reduced.
  • the transfer of lye to the HCE stage was measured and, provided that the pulp is dewatered to a consistency of 32%, was calculated to be 240 kg / t of dry cellulose.
  • Such low-viscosity cellulose ethers are suitable for use as coatings and protective colloids in emulsion polymerization reactions which require cellulose or cotton linters with an intrinsic viscosity of approximately 250 ml / g.
  • UBABD pulp was subjected to the following treatment and bleaching sequences: CCE-W-HCE / O-Z-P and HCE / O-W-CCE-Z-P, respectively.
  • CCE cold alkali extraction
  • W an intermediate wash
  • HCE hot alkali extraction
  • O an oxygen delignification
  • Z an ozone bleaching stage
  • P peroxide bleaching stage
  • E means a hot alkali extraction which is comparable to the HCE mentioned above, but is carried out under milder conditions.
  • the (E / O) -Z-P sequence was carried out under both standard (i.e. mild) and enhanced conditions.
  • the pulp was also processed according to the sequence CCE-W-HCE / OZP, but the alkali used for the CCE treatment was (a) with 20 g / 1 gamma-cellulose or (b) with 20 g / 1 beta -Cellulose contaminated.
  • the pulps were processed in a manner known per se to lyocell fibers with a titer of 1.3 dtex.
  • Beech sulfite EO-Z-P (standard) 0.80 1.26 34.2 10.0 Beech sulfite EO-Z-P (HCE finished) 0.76 1.24 35.1 11.0
  • lyocell fibers which have been produced from a UBABD pulp treated with both CCE and HCE have strengths which are comparable to those of the eucalyptus PHK pulp. These strengths are significantly higher than those achieved with UBABD pulp fibers made without CCE treatment.
  • the combination of a CCE and an HCE treatment results in UBABD pulps that can be used excellently for the production of Lyocell fibers, which fibers have strengths that were previously only achievable by using pre-hydrolysis Kraft pulps.
  • Fibers made from a pulp treated with a gamma-cellulose-contaminated CCE liquor according to case (a) above showed no significant deviation in strength.
  • a Lyocell fiber made from a pulp treated with a CCE liquor contaminated with beta-cellulose (case (b) above) has a lower strength.

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  • Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Wood Science & Technology (AREA)
  • Polysaccharides And Polysaccharide Derivatives (AREA)
  • Paper (AREA)

Abstract

L'invention concerne un procédé pour produire une pâte chimique, comprenant les étapes qui consistent : à obtenir une pâte de cellulose au moyen d'un procédé de désagrégation connu en soi ; à effectuer au moins une étape d'extraction alcaline, au cours de laquelle la pâte de cellulose est traitée au moyen d'une lessive, puis pressée ; à éventuellement effectuer des étapes supplémentaires de nettoyage et/ou de blanchiment de la pâte de cellulose. Selon l'invention, au moins une partie de la lessive qui reste après le processus de pressage lors de l'étape d'extraction alcaline peut être réutilisée pour traiter la pâte de cellulose. Le procédé selon l'invention est caractérisé en ce que la teneur en bêta-cellulose est réduite dans au moins une partie de la lessive réutilisée, avant le nouveau traitement de la pâte de cellulose.
PCT/AT2005/000171 2004-06-02 2005-05-20 Procede de production d'une pate chimique WO2005118950A1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
CA2568594A CA2568594C (fr) 2004-06-02 2005-05-20 Methode de production d'une pate pour transformation chimique
EP05741840.2A EP1753908B1 (fr) 2004-06-02 2005-05-20 Procede de production d'une pate chimique
NO20065354A NO338462B1 (no) 2004-06-02 2006-11-24 Framgangsmåte for framstilling av tremasse og anvendelse av samme

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
ATA953/2004 2004-06-02
AT9532004A AT413548B (de) 2004-06-02 2004-06-02 Verfahren zur herstellung eines chemiezellstoffes und seine verwendung

Publications (1)

Publication Number Publication Date
WO2005118950A1 true WO2005118950A1 (fr) 2005-12-15

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Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/AT2005/000171 WO2005118950A1 (fr) 2004-06-02 2005-05-20 Procede de production d'une pate chimique

Country Status (6)

Country Link
EP (1) EP1753908B1 (fr)
AT (1) AT413548B (fr)
CA (1) CA2568594C (fr)
NO (1) NO338462B1 (fr)
WO (1) WO2005118950A1 (fr)
ZA (1) ZA200610044B (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007128027A1 (fr) * 2006-05-10 2007-11-15 Lenzing Aktiengesellschaft Procédé de fabrication d'une pâte de cellulose
WO2007128024A1 (fr) * 2006-05-10 2007-11-15 Lenzing Aktiengesellschaft Procédé de fabrication d'une pâte de cellulose
WO2013159948A1 (fr) 2012-04-26 2013-10-31 Lenzing Aktiengesellschaft Séparateur de batterie
WO2014127828A1 (fr) 2013-02-22 2014-08-28 Lenzing Aktiengesellschaft Séparateur de batterie

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
AT503610B1 (de) * 2006-05-10 2012-03-15 Chemiefaser Lenzing Ag Verfahren zur herstellung eines zellstoffes
FI129086B (en) * 2012-09-14 2021-06-30 Teknologian Tutkimuskeskus Vtt Oy Method for producing soluble pulp
CN104611973A (zh) * 2013-11-04 2015-05-13 新疆光大山河化工科技有限公司 一种精制棉黑液处理工艺
EP3347522B1 (fr) * 2015-09-07 2020-06-17 Domsjö Fabriker AB Nouvelle pâte de dissolution
JP2017224611A (ja) * 2017-07-06 2017-12-21 レンツィング アクチェンゲゼルシャフト 電池セパレータ
SE1850733A1 (en) * 2018-06-15 2019-12-16 Valmet Oy Method and assembly for optimizing filtrate circulation in a kraft process
SE2250793A1 (en) * 2022-06-27 2023-12-28 Valmet Oy Method for processing cellulose pulp obtained from a kraft process

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3935022A (en) * 1973-07-23 1976-01-27 Hannes Sihtola Method for the removal of hemicellulose from hemicellulose-containing caustic liquors
US4270914A (en) * 1979-10-26 1981-06-02 Borregaard Industries Limited Process for controlling hemicellulose concentration during the mercerization of cellulose
US5589053A (en) * 1995-11-03 1996-12-31 Huron Tech Incorporated Electrolysis process for removal of caustic in hemicellulose caustic
WO1997023279A1 (fr) * 1995-12-23 1997-07-03 Krebs & Co. Ag Procede d'epuration d'un liquide pollue par des molecules filiformes

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3935022A (en) * 1973-07-23 1976-01-27 Hannes Sihtola Method for the removal of hemicellulose from hemicellulose-containing caustic liquors
US4270914A (en) * 1979-10-26 1981-06-02 Borregaard Industries Limited Process for controlling hemicellulose concentration during the mercerization of cellulose
US5589053A (en) * 1995-11-03 1996-12-31 Huron Tech Incorporated Electrolysis process for removal of caustic in hemicellulose caustic
WO1997023279A1 (fr) * 1995-12-23 1997-07-03 Krebs & Co. Ag Procede d'epuration d'un liquide pollue par des molecules filiformes

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007128027A1 (fr) * 2006-05-10 2007-11-15 Lenzing Aktiengesellschaft Procédé de fabrication d'une pâte de cellulose
WO2007128024A1 (fr) * 2006-05-10 2007-11-15 Lenzing Aktiengesellschaft Procédé de fabrication d'une pâte de cellulose
WO2013159948A1 (fr) 2012-04-26 2013-10-31 Lenzing Aktiengesellschaft Séparateur de batterie
WO2014127828A1 (fr) 2013-02-22 2014-08-28 Lenzing Aktiengesellschaft Séparateur de batterie

Also Published As

Publication number Publication date
ZA200610044B (en) 2008-02-27
ATA9532004A (de) 2005-08-15
CA2568594C (fr) 2013-07-16
NO20065354L (no) 2007-01-31
EP1753908B1 (fr) 2016-02-03
AT413548B (de) 2006-03-15
CA2568594A1 (fr) 2005-12-15
EP1753908A1 (fr) 2007-02-21
NO338462B1 (no) 2016-08-22

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