EP0325890B1 - Procédé de traitement d'une pâte cellulosique contenant de la lignine par l'ozone - Google Patents

Procédé de traitement d'une pâte cellulosique contenant de la lignine par l'ozone Download PDF

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Publication number
EP0325890B1
EP0325890B1 EP88810034A EP88810034A EP0325890B1 EP 0325890 B1 EP0325890 B1 EP 0325890B1 EP 88810034 A EP88810034 A EP 88810034A EP 88810034 A EP88810034 A EP 88810034A EP 0325890 B1 EP0325890 B1 EP 0325890B1
Authority
EP
European Patent Office
Prior art keywords
ozone
fatty acid
pulp
lignin
acid
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 - Lifetime
Application number
EP88810034A
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German (de)
English (en)
Other versions
EP0325890A1 (fr
Inventor
Horst H. Prof.-Dr. Nimz
Alex Dipl.-Ing. Berg
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.)
Acetocell GmbH and Co KG
Original Assignee
Acetocell GmbH and Co KG
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
Priority to EP88810034A priority Critical patent/EP0325890B1/fr
Application filed by Acetocell GmbH and Co KG filed Critical Acetocell GmbH and Co KG
Priority to ES198888810034T priority patent/ES2041828T3/es
Priority to AT88810034T priority patent/ATE90404T1/de
Priority to DE8888810034T priority patent/DE3881676D1/de
Priority to CA000588913A priority patent/CA1319472C/fr
Priority to BR898900299A priority patent/BR8900299A/pt
Priority to JP1017414A priority patent/JPH01221587A/ja
Publication of EP0325890A1 publication Critical patent/EP0325890A1/fr
Priority to US07/606,595 priority patent/US5074960A/en
Application granted granted Critical
Publication of EP0325890B1 publication Critical patent/EP0325890B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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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
    • D21C9/10—Bleaching ; Apparatus therefor
    • D21C9/147—Bleaching ; Apparatus therefor with oxygen or its allotropic modifications
    • D21C9/153—Bleaching ; Apparatus therefor with oxygen or its allotropic modifications with ozone
    • 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

Definitions

  • the invention relates to a method for treating lignin-containing cellulose mass, i.e. Ligno cellulose or pulp.
  • lignin-containing cellulose mass i.e. Ligno cellulose or pulp.
  • “Lignocelluloses” are understood here to mean the macromolecular substances which, in addition to cellulose, also contain hemicelluloses and lignin, such as e.g. is the case with wood.
  • the removal of lignin from cellulose or wood is also referred to as "delignification”.
  • the raw material consisting of wood or woody annual plants, usually in a mechanically crushed state, is chemically digested.
  • acetic acid is used instead of the conventional digestion chemicals based on sulfur compounds, which are problematic for disposal. This method, also known as the acetosol method, offers a significant reduction in environmental pollution compared to conventional methods.
  • the pulps obtained from the Acetosolv digestion can still contain up to 4% residual lignin, which usually has to be removed by a bleaching treatment.
  • hydrogen peroxide is added as the bleaching agent, which combines with the acetic acid to form peracetic acid, which is considered a selective lignin oxidizing agent.
  • this bleaching has so far only led to satisfactory degrees of whiteness with hardwood pulp, and even then only with a relatively high consumption of hydrogen peroxide:
  • several bleaching stages with bleaches containing chlorine are used to achieve high degrees of whiteness. As a result, chlorine-containing organic compounds are formed in the waste liquors, which lead to serious wastewater problems.
  • ozone In addition to hydrogen peroxide and oxygen, ozone has also been proposed as a chlorine-free bleach. Despite great efforts, however, ozone has not yet been used technically as a bleaching agent, because the reaction of ozone in water with hydroxyl ions generates hydroxyl radicals, which break down the cellulose molecules and thus lower the strength properties of the pulp and prejudice the use of ozone as Have established bleach in the pulp production.
  • ABIPC 6233 (Volume 54, No. 6, December 1983) describes a further investigation of the effect of sulfuric acid, acetic acid, chemical additives and process variables on the ozone bleaching of sulfate cellulose. Also in this publication, there are no indications of the suitability of concentrated C1 ⁇ 3 fatty acids or acetic acid as a selective solvent or extraction agent for oxidized lignin.
  • the inventive method for the treatment of cellulose mass with ozone has the features indicated in the characterizing part of claim 1.
  • ozone concentration is increased and, on the other hand, side reactions due to ozone decomposition products can be reduced.
  • low fatty acids react as radical scavengers with OH radicals and can thus prevent these very unselective radicals from attacking cellulose.
  • the ozone itself does not have a radical effect, but preferably electrophilic, as a result of which the lignin is selectively attacked and broken down into soluble products.
  • ozone in low fatty acids increases its effectiveness as a bleaching agent and thus reduces ozone consumption, which is of fundamental importance for technical use.
  • acetic acid is a better solvent for lignin than water, while the reverse is true for cellulose, which further increases the selectivity of ozone as a delignifying agent.
  • cellulose mass in the claims and the description denotes all masses (including starting materials) which are suitable for the production of cellulose or cellulose and cellulose (here includes both ⁇ -cellulose and the hemicelluloses sometimes referred to as ⁇ - or ⁇ -cellulose). as well as lignin included.
  • acetic acid and propionic acid are suitable as C1 ⁇ 3 fatty acids.
  • Acetic acid is preferred.
  • Mixtures of such acids with one another and / or with water in limited proportions are also suitable, the water content of the fatty acid, the fatty acid mixture or the preferred acetic acids being less than 50% by weight, in particular less than 30% by weight, and usually 1 to 10% by weight. % is.
  • a low water content of e.g. 5 to 10% by weight, i.e. a 90 to 95% acetic acid is particularly preferred.
  • Ozone obtainable with conventional generators is contained in the gas phase which surrounds the mixture combined with fatty acid, for example consisting of 2 to 50% by weight cellulose mass and 98 to 50% by weight fatty acid.
  • the interaction between the cellulose mass / fatty acid mixture on the one hand and the gas phase or the ozone contained therein on the other hand can be influenced in particular by movement or / and the amount of ozone present and / or the temperature. Through movement, both the mixing intensity and the distribution of the solid and liquid phases can be influenced or varied and adapted. Conventional mixing devices that are sufficiently resistant to the components can be used for this purpose; Mixers with a pronounced shear effect on the mix are not preferred.
  • the amount of ozone present in the gas phase can be influenced by the gas pressure and / or the ozone concentration in the gas phase.
  • a gas phase which mainly consists of air.
  • the ozone concentration of a gas phase suitable for the process and consisting predominantly of air or oxygen under normal or slight excess pressure is 0.1 to 10%, generally 1 to 3%. These values are based on the gas volume.
  • amounts of ozone of 1 to 2% by weight, but also even higher concentrations, can be used without adverse effects for the pulp obtained when working at the preferred temperatures of 0 to 30 ° C.
  • the working temperature (measured in the cellulose mass or the gas phase) is below 100 ° C, in particular below 50 ° C.
  • the process according to the invention offers particular advantages when it is used as a delignification stage for pulp bleaching, in which the starting material, in particular wood, is digested with acetic acid, for example by the process described in DE-A-3 445 132.
  • the starting material in particular wood
  • acetic acid for example by the process described in DE-A-3 445 132.
  • coniferous wood eg spruce wood
  • this offers considerable advantages because the peroxide consumption is then comparatively high in the known treatment with peroxides.
  • kappa values or kappa numbers given here were determined using the method described in Leaflet IV / 37/80 of the Technical Committee for Chemical Pulp and Paper Testing in the Association of Pulp and Paper Chemists and Engineers (BR Germany).
  • Whiteness levels in the range just mentioned can also be achieved if bleaching is carried out first with peracetic acid and then with ozone. According to the prior art, whitenesses of over 70% ISO after digestion of acetic acid could only be achieved with relatively large amounts of peroxide. According to the invention, degrees of whiteness of over 80% ISO can be achieved if the pulp is first bleached with ozone in a three-stage bleach (Z), then treated with H2O2 (P) and finally again with ozone (Z) or with a PZP bleaching sequence in the same solvent, ie C1 ⁇ 3 fatty acid or acetic acid.
  • the process according to the invention is particularly advantageous as a process stage in a "countercurrent process" which e.g. with known carousel extractors according to the information in the magazine "Wood as raw and material", 44 (1986) 207-212, can be carried out;
  • acetic acid with or without ozone is used not only for the final extraction, but as the only lignin solvent.
  • operation with a low consistency, preferably 2 to 10% pulp, and ozone concentrations below 2%, preferably 0.5 to 1.5%, is possible.
  • the acetic acid should contain less than 50% by weight of water, preferably less than 30% by weight and in particular less than 10% by weight of water.
  • an addition of another substance, in particular another C1 ⁇ 3 fatty acid, can also serve, i.e. it can also be used with acetic acid, e.g. Contains 1 to 50 wt.% Propionic and / or formic acid.
  • devices known per se are suitable for carrying out the method according to the invention as a separate treatment or as a step in a sequence of treatments or processing operations in the production of cellulose, which devices have at least one chamber or zone for receiving the fat or.
  • Cellulose mass containing acetic acid if these devices have devices known per se for treatment with a gas phase containing ozone.
  • the parts of the device which come into contact with the mass or the gas phase consist of correspondingly resistant materials, preferably steel alloys.
  • the properties e.g. the characteristic values of the pulp obtained, such as tear length, rupture area and tear resistance, were not significantly changed by the treatment with ozone by the process according to the invention; the process according to the invention enables pulp products to be obtained, the quality of which corresponds to that of the conventional pulps obtainable by the sulfate process and is considerably better than that of the products obtained by the sulfite process.
  • the invention is illustrated by the following examples.
  • the term DP w means the degree of polymerization, based on the weight average molecular weight.
  • the ozone treatment can drastically reduce peroxide consumption and still achieve a whiteness of over 70% without the mechanical product properties suffering.
  • the fatty acid used for the process according to the invention can be worked up and recirculated in an environmentally friendly manner in a manner known per se, for example by azeotropic distillation.
  • the distillation residue containing the lignin can also be worked up in an environmentally friendly manner, for example burned.
  • pulp which was made from pine chips (Pinus sylvestris, 45 years) according to the Acetosolv process (Kappa number 24.2), is pressed down to a moisture content of 35% and then mechanically crushed.
  • the shredded material is placed in a flask and treated with 1 to 3.3% ozone (0.05 g ozone / min, 0.06 g ozone / liter oxygen). After an exposure time of 10 to 40 minutes, the pulp washed with acetic acid and then with water.
  • C1 ⁇ 3 fatty acid mixtures which, for example, are available in the hydrolysis of plant waste and consist of mixtures of acetic acid, propionic acid and formic acid.

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Wood Science & Technology (AREA)
  • Paper (AREA)
  • Compounds Of Unknown Constitution (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Polysaccharides And Polysaccharide Derivatives (AREA)
  • Silicates, Zeolites, And Molecular Sieves (AREA)

Claims (8)

  1. Procédé de traitement à l'ozone d'une masse cellulosique contenant de la lignine en présence d'acide gras C₁₋₃, caractérisé en ce que la masse cellulosique, mélangée à au moins un acide gras C₁₋₃ contenant moins de 50% en poids en eau, est soumise à l'action d'une phase gazeuse qui contient de l'ozone dans un rapport de 0,1 à 10% en volume, de sorte à augmenter la solubilité de la lignine dans l'acide gras C₁₋₃ par une modification oxydante de ladite lignine, et que ladite lignine ainsi modifiée est séparée en même temps que l'acide gras C₁₋₃ de la masse cellulosique.
  2. Procédé selon la revendication 1, caractérisé en ce que l'acide gras C₁₋₃ utilisé est de l'acide acétique.
  3. Procédé selon la revendication 1 ou 2, caractérisé en ce que le traitement de la masse cellulosique à l'ozone est effectué à une température inférieure à 100 °C, de préférence inférieure à 50 °C, et en particulier comprise entre 0 et 30 °C.
  4. Procédé selon l'une des revendications 1 à 3, caractérisé en ce que ce procédé est employé en temps qu'étape de délignification à l'aide d'un acide gras C₁₋₃ dans la production de cellulose blanchie, étape dans laquelle l'acide gras C₁₋₃ utilisé est un constituant de l'agent liquide de dissolution employé dans une étape précédente, et sert de milieu liquide de traitement lors d'un blanchissage au peroxyde.
  5. Procédé selon la revendication 4, caractérisé en ce que le traitement à l'ozone dans l'acide gras C₁₋₃, en particulier dans l'acide acétique, est effectué avant et/ou après un traitement à l'acide peracétique.
  6. Procédé selon la revendication 4 ou 5, caractérisé en ce qu'il constitue une étape dans un procédé à contre-courant.
  7. Procédé selon l'une des revendications 4 à 6, caractérisé en ce que la concentration en cellulose se situe entre 1 et 50%, de préférence entre 25 et 40%, et que la concentration en ozone dans l'acide gras C₁₋₃ est inférieure à 3%, et se situe de préférence entre 0,1 et 1,5% par rapport au poids à sec de la masse cellulosique.
  8. Procédé selon l'une des revendications 1 à 7, caractérisé en ce que la teneur en eau de l'acide gras, ou du mélange contenant cet acide gras, est de 1 à 10% en poids.
EP88810034A 1988-01-25 1988-01-25 Procédé de traitement d'une pâte cellulosique contenant de la lignine par l'ozone Expired - Lifetime EP0325890B1 (fr)

Priority Applications (8)

Application Number Priority Date Filing Date Title
ES198888810034T ES2041828T3 (es) 1988-01-25 1988-01-25 Procedimiento para el tratamiento de masa de celulosa conteniendo lignina, con ozono.
AT88810034T ATE90404T1 (de) 1988-01-25 1988-01-25 Verfahren zur behandlung von lignin enthaltender cellulosemasse mit ozon.
DE8888810034T DE3881676D1 (de) 1988-01-25 1988-01-25 Verfahren zur behandlung von lignin enthaltender cellulosemasse mit ozon.
EP88810034A EP0325890B1 (fr) 1988-01-25 1988-01-25 Procédé de traitement d'une pâte cellulosique contenant de la lignine par l'ozone
CA000588913A CA1319472C (fr) 1988-01-25 1989-01-23 Procede d'elimination de la lignine
BR898900299A BR8900299A (pt) 1988-01-25 1989-01-25 Processo para a separacao de lignina de massa de celulose,dispositivo para a realizacao do processo e massa de celulose preparada pelo processo
JP1017414A JPH01221587A (ja) 1988-01-25 1989-01-25 パルプからリグニンを除去する方法
US07/606,595 US5074960A (en) 1988-01-25 1990-10-31 Lignin removal method using ozone and acetic acid

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP88810034A EP0325890B1 (fr) 1988-01-25 1988-01-25 Procédé de traitement d'une pâte cellulosique contenant de la lignine par l'ozone

Publications (2)

Publication Number Publication Date
EP0325890A1 EP0325890A1 (fr) 1989-08-02
EP0325890B1 true EP0325890B1 (fr) 1993-06-09

Family

ID=8200568

Family Applications (1)

Application Number Title Priority Date Filing Date
EP88810034A Expired - Lifetime EP0325890B1 (fr) 1988-01-25 1988-01-25 Procédé de traitement d'une pâte cellulosique contenant de la lignine par l'ozone

Country Status (8)

Country Link
US (1) US5074960A (fr)
EP (1) EP0325890B1 (fr)
JP (1) JPH01221587A (fr)
AT (1) ATE90404T1 (fr)
BR (1) BR8900299A (fr)
CA (1) CA1319472C (fr)
DE (1) DE3881676D1 (fr)
ES (1) ES2041828T3 (fr)

Families Citing this family (23)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA2053035C (fr) * 1990-10-12 1997-09-30 Repap Enterprises Inc. Pates de bois sans chlore, et procede de fabrication
DE4107357C1 (fr) * 1991-03-08 1992-11-05 Acetocell Gmbh & Co Kg, 7162 Gschwend, De
DE4107354C1 (fr) * 1991-03-08 1992-11-05 Acetocell Gmbh & Co Kg, 7162 Gschwend, De
SE470234B (sv) * 1992-05-13 1993-12-13 Kamyr Ab Sätt vid blekning av cellulosahaltigt fibermaterial med ozon i närvaro av en organisk förening
JP3121917B2 (ja) * 1992-07-08 2001-01-09 住友重機械工業株式会社 オゾンによるパルプ漂白方法
DE4228171C2 (de) * 1992-08-25 1995-06-14 Kaemmerer Projekt Agentur Gmbh Verfahren zur Gewinnung von Zellstoffen
US5387317A (en) * 1993-01-28 1995-02-07 The Mead Corporation Oxygen/ozone/peracetic aicd delignification and bleaching of cellulosic pulps
US5411635A (en) * 1993-03-22 1995-05-02 The Research Foundation Of State University Of New York Ozone/peroxymonosulfate process for delignifying a lignocellulosic material
JP3312138B2 (ja) * 1998-12-02 2002-08-05 独立行政法人 森林総合研究所 木質板およびその製法
US6468953B1 (en) 2000-08-03 2002-10-22 Lynntech, Inc. Methods of preparing antimicrobial compositions comprising ozone
AU2002225936A1 (en) * 2000-11-03 2002-05-15 Penwest Pharmaceutical Company Process for producing microcrystalline cellulose with a desired dp
US20020107288A1 (en) * 2000-12-08 2002-08-08 Singh Waheguru Pal Methods of sterilizing with dipercarboxylic acids
WO2005064076A1 (fr) * 2003-12-25 2005-07-14 Xiuquan Mei Procede de reduction en pate par oxydation en cycle ferme sans rejet
US7824521B2 (en) * 2006-12-18 2010-11-02 University Of Maine System Board Of Trustees Process of treating a lignocellulosic material with hemicellulose pre-extraction and hemicellulose adsorption
US20100159522A1 (en) * 2008-12-19 2010-06-24 E.I. De Pont De Nemours And Company Organosolv and ozone treatment of biomass to enhance enzymatic saccharification
WO2010080489A1 (fr) * 2008-12-19 2010-07-15 E. I. Du Pont De Nemours And Company Application d'un traitement à l'ozone à de la biomasse pour une meilleure saccharification enzymatique
US8216809B2 (en) * 2008-12-19 2012-07-10 E I Du Pont De Nemours And Company Organic solvent pretreatment of biomass to enhance enzymatic saccharification
EP2513150A1 (fr) * 2009-12-18 2012-10-24 Shell Internationale Research Maatschappij B.V. Procédé pour l'extraction de sucres et de lignine à partir de biomasse solide comprenant de la lignocellulose
US9382282B2 (en) * 2011-09-09 2016-07-05 University Of Tennessee Research Foundation Metal catalyzed oxidation of lignin and related compounds
ES2386045B1 (es) * 2012-05-03 2013-04-18 Saica Pack, S.L. Procedimiento de obtención de celulosa nanofibrilada a partir de papel recuperado
ES2384931B1 (es) * 2012-05-03 2013-03-20 Saica Pack, S.L. Procedimiento de obtención de celulosa nanodispersada a partir de papel recuperado
FR3016359B1 (fr) * 2014-01-10 2022-04-29 Arkema France Compositions de peroxyde d'hydrogene pour la delignification de matiere vegetale et leurs utilisations
US10745335B2 (en) 2016-07-14 2020-08-18 University Of Kansas Continuous process for the ozonolysis of lignin to yield aromatic monomers

Family Cites Families (6)

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Publication number Priority date Publication date Assignee Title
US3553076A (en) * 1968-01-22 1971-01-05 Weyerhaeuser Co Non-catalytic process for the production of cellulose from lignocellulosic materials using acetic acid
US4119486A (en) * 1975-08-14 1978-10-10 Westvaco Corporation Process for bleaching wood pulp with ozone in the presence of a cationic surfactant
CA1090510A (fr) * 1976-06-02 1980-12-02 Arthur W. Kempf Delignification et blanchiment par l'ozone d'une pate lignocellulosique liquide
US4372812A (en) * 1978-04-07 1983-02-08 International Paper Company Chlorine free process for bleaching lignocellulosic pulp
US4278477A (en) * 1980-03-19 1981-07-14 Amchem Products, Inc. Metal treatment
DE3445132A1 (de) * 1984-12-11 1986-06-12 Nimz, Horst H., Prof.Dr., 2050 Hamburg Holzaufschluss mit essigsaeure

Also Published As

Publication number Publication date
US5074960A (en) 1991-12-24
ATE90404T1 (de) 1993-06-15
JPH01221587A (ja) 1989-09-05
CA1319472C (fr) 1993-06-29
ES2041828T3 (es) 1993-12-01
EP0325890A1 (fr) 1989-08-02
DE3881676D1 (de) 1993-07-15
BR8900299A (pt) 1989-09-19

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