EP3894445A1 - Composition présentant un xylane et procédé de préparation d'une composition présentant un xylane - Google Patents

Composition présentant un xylane et procédé de préparation d'une composition présentant un xylane

Info

Publication number
EP3894445A1
EP3894445A1 EP19783334.6A EP19783334A EP3894445A1 EP 3894445 A1 EP3894445 A1 EP 3894445A1 EP 19783334 A EP19783334 A EP 19783334A EP 3894445 A1 EP3894445 A1 EP 3894445A1
Authority
EP
European Patent Office
Prior art keywords
precipitation
xylan
aqueous alkaline
alkaline solution
composition
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.)
Pending
Application number
EP19783334.6A
Other languages
German (de)
English (en)
Inventor
Robin Rohringer
Gregor Kraft
Erwin Malzner
Christian SPERGER
Michael Lammer
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.)
Lenzing AG
Original Assignee
Lenzing AG
Chemiefaser Lenzing AG
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 AG, Chemiefaser Lenzing AG filed Critical Lenzing AG
Publication of EP3894445A1 publication Critical patent/EP3894445A1/fr
Pending legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08B—POLYSACCHARIDES; DERIVATIVES THEREOF
    • C08B37/00—Preparation of polysaccharides not provided for in groups C08B1/00 - C08B35/00; Derivatives thereof
    • C08B37/0006—Homoglycans, i.e. polysaccharides having a main chain consisting of one single sugar, e.g. colominic acid
    • C08B37/0057—Homoglycans, i.e. polysaccharides having a main chain consisting of one single sugar, e.g. colominic acid beta-D-Xylans, i.e. xylosaccharide, e.g. arabinoxylan, arabinofuronan, pentosans; (beta-1,3)(beta-1,4)-D-Xylans, e.g. rhodymenans; Hemicellulose; Derivatives thereof
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L5/00—Compositions of polysaccharides or of their derivatives not provided for in groups C08L1/00 or C08L3/00
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L5/00—Compositions of polysaccharides or of their derivatives not provided for in groups C08L1/00 or C08L3/00
    • C08L5/14—Hemicellulose; Derivatives thereof

Definitions

  • the invention relates to a process for the preparation of a xylan-containing composition, in which an aqueous alkaline solution, which has hemicelluloses, acid is added and a precipitate containing xylan is precipitated from the resulting precipitation suspension.
  • Hemicelluloses are generally understood to mean polyoses from pentoses and / or hexoses, such as xylose, arabinose, glucose, mannose or galactose. Hemicelluloses refer in particular to all polysaccharides except cellulose, which occurs as a component of plant cell walls, the matrix of which consists of fibrillar, partly crystalline cellulose, as well as low-molecular breakdown products of cellulose, e.g. hydroxycarboxylic acids, which can be formed in the course of digestion processes. In contrast to cellulose, which is a non-branched homopolymer of glucose, hemicelluloses are generally branched heteropolymers from the above-mentioned pentoses and hexoses.
  • Hemicelluloses also have significantly lower degrees of polymerization or chain lengths than cellulose. Such hemicelluloses can be, for example, xylans, mannans, galactans, or other pentosans or hexosans. Vegetable heteropolysaccharides with a D-xylose as the main repeating unit (monomer unit) are referred to as xylans.
  • xylans Vegetable heteropolysaccharides with a D-xylose as the main repeating unit (monomer unit) are referred to as xylans.
  • xylans A distinction between celluloses (a fraction) and hemicelluloses (ß and g fractions) is defined in the prior art by the solubility in 17.5% sodium hydroxide solution (WÜSTENBERG, Tanja.
  • ⁇ - and g-hemicelluloses can be dissolved in 17.5% sodium hydroxide solution, a-cellulose is insoluble. In the subsequent neutralization, the ⁇ -hemicelluloses then precipitate out, while the g-hemicelluloses remain in solution.
  • WO 2007/128025 A1 discloses a process for the preparation of a composition containing xylan, in which an aqueous alkaline solution which has hemicelluloses is mixed with a dilute sulfuric acid, the pH of the aqueous solution being between 4 and 5 sets. The resulting precipitate after 6-8 h is then centrifuged, washed and dried.
  • Such processes suffer from low chain length and size selectivity in the precipitation of the hemicelluloses, which leads to a reduced yield.
  • the lengthy precipitation process results in reduced throughput and higher manufacturing costs.
  • the invention solves the problem in that acid is continuously added to the aqueous alkaline solution until the pH falls below 4 in the precipitation suspension and the temperature of the precipitation suspension during the precipitation does not fall below 40 ° C. If acid is continuously added to the precipitation suspension until the pH falls below 4 in the precipitation suspension, the yield and quality of the precipitate produced can be significantly improved. At pH values below 4, very advantageous conditions for a complete precipitation of the hemicelluloses can be created. In addition, if the temperature of the precipitation suspension during the precipitation does not fall below a precipitation temperature of at least 40 ° C., an optimal particle size distribution can also be ensured during the precipitation.
  • the average particle size can be increased, which enables better filterability of the precipitate.
  • a production process of the type mentioned at the outset with higher yield and higher cost efficiency can thus be created.
  • the method according to the invention is independent of the composition of the pulp from which the aqueous alkaline solution was produced. If aqueous alkaline solutions from the production of beech wood pulp or the alkalization of beech wood pulp are used, a composition containing xylan with high quality and purity can be created.
  • the aqueous alkaline solution has a pH of at least 8, in particular at least 1 1, it can be ensured that all hemicelluloses are present in solution in the aqueous alkaline solution. This is conducive to easier processing of the solution, since undesired formation of precipitates in the aqueous solution can be reliably prevented. A particularly reliable process with improved yield can thus be created.
  • the yield of the method can be further improved if the aqueous alkaline solution has between 5 g / l and 150 g / l, in particular between 30 g / l and 70 g / l, hemicelluloses. If the aqueous alkaline solution has such a hemicellulose content, a higher quality precipitate can be created. In particular, the concentration of xylan in the precipitate can be increased further by concentrating the hemicelluloses in the aqueous alkaline solution.
  • the inventive method can be further improved if the acid is continuously added to the aqueous alkaline solution with constant stirring. By slowly adding the acid, large jumps in pH can be avoided.
  • the acid added as a precipitant can preferably be a water-miscible organic or inorganic acid, for example sulfuric acid or acetic acid.
  • acid is added to the aqueous alkaline solution until a precipitation suspension with a pH of less than 3 is obtained.
  • acid is added to the aqueous alkaline solution until the pH of the precipitation suspension falls below 2.5.
  • the pH of the precipitation suspension is decisive for the yield and quality of the precipitate produced, since complete precipitation of the desired ⁇ -hemicelluloses, namely in particular the xylan, can only be guaranteed if the pH falls below a certain value.
  • a method for producing a xylan-containing composition can thus be created with high yield and high reliability. If the temperature falls below the precipitation suspension during the
  • the particle size distribution in the precipitation can be further optimized. It can be particularly advantageous if the precipitation temperature is at least 60 ° C. and the precipitation suspension during the precipitation also does not exceed a temperature of 95 ° C.
  • the particle size and molar mass distribution of the precipitate are strongly influenced by the temperature during the precipitation due to the thixotropy of the precipitation suspension. At low precipitation temperatures, very small hemicellulose particles with a low DP value (degree of polymerization) preferably precipitate out, while at high precipitation temperatures it is mainly hemicelluloses with a high DP value that precipitate out.
  • the desired properties of the precipitate with regard to particle size and molar mass can thus be controlled by suitable selection of the precipitation temperature.
  • a precipitate which can be filtered particularly easily from the supernatant can be created, as a result of which the yield of the process can be further improved.
  • the process can be made more reliable if the aqueous alkaline solution is heated to at least the precipitation temperature before adding the acid.
  • an aqueous alkaline solution can be fed directly, which already has a temperature higher than the precipitation temperature.
  • the aqueous alkaline solution is also at a maximum heating rate of
  • the inventive method can be particularly characterized in that at least 90% of the xylan-containing precipitate has a particle size of greater than 5 pm after the precipitation. If the particle size of the precipitate is above 5 pm, a precipitate that can be separated particularly well from the supernatant can be produced, as a result of which the yield of the process can be further increased.
  • the precipitate containing xylan is separated from the supernatant after the precipitation, in particular by filtering, a particularly simple method for producing a composition comprising xylan can be provided. If the supernatant is also washed and / or dried, the quality of the process product can be further improved.
  • the inventive method is particularly suitable if the hemicellulose-containing aqueous alkaline solution is a waste liquor from a pulp or viscose production.
  • the aqueous alkaline solution can be a press liquor, which is obtained or obtained in a viscose process, for example in the alkalization of pulp with sodium hydroxide solution to alkali cellulose and subsequent pressing of the alkalized pulp.
  • a press liquor typically contains 100-300 g / l sodium hydroxide solution and has a hemicellulose content of between 5-150 g / l, in each case based on the total volume of the press liquor.
  • Such a press liquor advantageously has from 150 to 250 g / l sodium hydroxide solution.
  • the hemicellulose content is advantageously between 30 and 70 g / l.
  • Another object of the invention is to provide a composition containing xylan, which is characterized by low contamination and high xylan content and thus in particular by high tolerance in the human or animal body.
  • the invention solves this problem by a composition which, based on its dry substance, has at least 85% by weight of polysaccharides from ß-hemicelluloses containing xylan and contains the rest of ash, water and unavoidable impurities.
  • composition according to the invention can also be distinguished if it has at least 80% by weight of xylan, based on its dry substance. If the composition, based on its dry substance, has at least 84% by weight of xylan or, in further advantageous embodiments of the invention, at least 88% by weight or 90% by weight of xylan, a particularly high-quality product with high compatibility and versatility can be used Opportunity to be created.
  • the composition can be further improved if it has less than 10% by weight, in particular at most 8% by weight, of glucan and less than 1% by weight of other polysaccharides, based on its rock substance. Because of the particularly low glucan content, the composition can be particularly suitable for medical applications and has a high tolerance in the human and / or animal body.
  • composition of the invention according to any one of claims 1 1 to 13 can be particularly suitable for use as a tablet excipient in medicines. Because of their special swelling properties, xylans can be used as tablet disintegrants and the need for synthetic ones
  • composition of the invention according to any one of claims 1 1 to 13 can also be advantageously used for the production of xylan sulfate.
  • Sulphated xylans can be used, for example, as antivirals, anticancerogens or anticoagulants.
  • FIG. 1 shows a schematic representation of an embodiment of the method according to the invention in a first method step
  • FIG. 2 shows a schematic illustration of the method from FIG. 1 in a further method step
  • FIG. 3 shows a schematic illustration of the method from FIGS. 1 and 2 in a third method step.
  • FIGS. 1 to 3 schematically illustrate a method 100 for producing a
  • Xylan-containing composition 1 shown in different stages of the process.
  • An aqueous alkaline solution 2 which contains hemicelluloses 3 and is used, for example, as waste liquor 201 in a cellulose or viscose production 200, serves as the starting material for the method 100.
  • the aqueous alkaline solution 2 is a waste liquor 201 which is obtained in an alkalization step 203 in the alkalization of pulp 204 with alkali 205 as part of a viscose process 200.
  • the alkalized pulp 206 is pressed out in a press 207 and the waste liquor 202 is obtained as press liquor 201, which is fed to the process 100 according to the invention as an aqueous alkaline solution 2.
  • the method 100 according to the invention can be independent or part of the viscose method 200.
  • the aqueous alkaline solution 2 is fed in a first process step from the viscose process through a first inlet 11 to a container 10.
  • the container 10 also has a second inlet 12, via which acid 4 can be supplied.
  • the aqueous alkaline solution 2 is brought to at least the precipitation temperature - which is in a Embodiment variant is at least 40 ° C, in another embodiment variant at least 50 ° C and in another embodiment variant at least 60 ° C - heated, whereby a maximum heating rate of 50 ° C / h is not exceeded during the heating.
  • the heating can take place via a heater 13 integrated in the container.
  • the heater 13 can be connected upstream of the first inlet 11 and heat the aqueous alkaline solution 2 in one pass.
  • the aqueous alkaline solution 2 is fed directly from the viscose process 200 as the aqueous alkaline solution 2 which has already been heated above the precipitation temperature. Additional heating can thus be avoided.
  • the aqueous alkaline solution 2 has a pH of at least 8, such as at least 9, such as at least 10, such as at least 1 1.
  • the aqueous alkaline solution has between 5 and 150 g / l, such as between 10 and 120 g / l, such as between 20 and 100 g / l, such as between 30 and 70 g / l hemicelluloses.
  • the hemicelluloses 3 contained in the aqueous alkaline solution 2 can essentially be divided into ⁇ -hemicelluloses 31 and g-hemicelluloses 32, as described in the introductory part of the description.
  • ⁇ -hemicelluloses 31 and g-hemicelluloses 32 are dissolved in the aqueous alkaline solution 2.
  • FIG. 2 shows the method 100 according to the invention in a second method step after the aqueous alkaline solution 2 has been fed to the container 10 and heated above the precipitation temperature.
  • acid 4 is added to the aqueous alkaline solution 2 through the second inlet 12 to the container 10 until the pH of the precipitation suspension 5 obtained therein falls below 4.
  • acid 4 is added to the alkaline solution 2 until a pH of less than 3, for example less than 2.5, is reached in the precipitation suspension 5 obtained.
  • the acid 4 is continuously added through the second inlet 12 with constant stirring to the aqueous alkaline solution 2 in the container 10 in order to achieve a homogeneous distribution of the pH in the precipitation suspension 5 to guarantee.
  • the constant stirring in the container 10 can take place according to the embodiment shown in FIG. 2 by a stirring device 14 integrated in the container 10.
  • Such an acid 4 can be, for example, acetic acid, sulfuric acid, silicic acid or another water-soluble organic or inorganic acid.
  • the acid 4 is added to the alkaline solution 2, as shown in FIGS. 1 to 3, in the container 10 in batches or in a batch process. Alternatively, however, is in another
  • Embodiment possible that the addition of acid 4 to the alkaline solution 2 takes place in a continuous process, but this was not shown in the figures.
  • the temperature of the precipitation suspension 5 is kept above a precipitation temperature of at least 40 ° C. in order to achieve an advantageous particle distribution in the precipitate 6 (see FIG. 3).
  • the precipitation temperature is at least 50 ° C, such as at least 60 ° C.
  • the temperature of the precipitation suspension 5 should not exceed 95 ° C. in order to ensure the best possible yield. Therefore, the supply of the acid 4 should be slow and continuous in order to avoid excessive temperature increases, which can be caused by the exothermic neutralization reaction between the aqueous alkaline solution 2 and the acid 4.
  • the precipitation suspension 5 can be further heated by the heater 13 in order to keep the temperature of the precipitation suspension 5 above the desired precipitation temperature.
  • the method 100 according to the invention is in a third
  • the xylan-containing precipitate 6 was precipitated from the precipitation suspension 5.
  • the precipitation suspension 5 is separated into a supernatant 7, which is essentially free of ⁇ -hemicelluloses 31, and a precipitate 6, which essentially consists of ⁇ -hemicelluloses 31.
  • the supernatant 7 also contains the g-hemicelluloses 32, which are not precipitated.
  • at least 90% of the particles 8 in the xylan-containing precipitate 6 have a after the precipitation Particle size greater than 5 pm.
  • at least 95% of the particles 8 have a particle size of greater than 5 pm.
  • the precipitate 6 and the supernatant 7 can be fed to a filter 16 after the precipitation through an outlet 15 of the container 10 in order to separate the precipitate 6 from the supernatant 7.
  • the membrane of the filter 16 is chosen such that an unimpeded passage of the supernatant 7 and the g-hemicelluloses 32 contained therein is made possible, while the precipitate 6 with the ⁇ -hemicelluloses 31 is reliably retained.
  • a microfilter membrane with a pore size between 0.1 pm and 1 pm can be used.
  • the supernatant 7 passes through the filter as permeate 18 and can be used for further use as recovered alkali liquor 208 in a viscose or cellulose process 200.
  • the recovered alkaline liquor 208 can at least partially be used as the liquor 205 for alkalizing pulp 204 in the alkalizing step 203, thereby creating an extremely efficient and cost-effective viscose or pulp process 200, which comprises the process 100 according to the invention.
  • the precipitate 6 leaves the filter 16 as the retentate 17 and is then washed and dried as a filtered precipitate 8 via a conveyor unit 19 and a washing and drying unit 20.
  • the filtered precipitate 8 is dried using a dryer 20 with indirect heating in order to avoid damage to the temperature-sensitive ⁇ -hemicelluloses 31.
  • the washed and dried precipitate 9 can optionally also be comminuted, for example ground, to obtain a xylan-containing composition 1 with uniform properties.
  • the entire batch 21 of composition 1 containing xylan is then subjected to an analytical quality control and a specification for batch 21 is drawn up. The batch 21 can then be assembled and packaged as desired. Examples
  • Eluent B 350 mM sodium hydroxide solution (NaOH)
  • Post column reagent 350 mM sodium hydroxide solution (NaOH) - 0.8 ml / min
  • the anion exchange chromatography is regularly calibrated using sample standards (for example, glucose, xylose, mannose) in order to ensure a constantly high level of accuracy.
  • sample standards for example, glucose, xylose, mannose
  • the contents given in Tables 2 and 3 relate in percentages by weight (% by weight) to the dry mass of the composition (abbreviated:% TM).
  • the dry matter content is given in percent by weight (% by weight) based on the total weight of the composition.
  • % TM dry mass of the composition
  • other, not explicitly mentioned polyoses may be contained, the sum of which does not exceed 0.1% DM.
  • Table 2 Specifications of Examples B1 to B4 according to the invention.
  • compositions according to Examples B1 to B4 all have a xylan content of greater than 80% by weight, based on the dry matter.
  • the glucan content in all examples is below 10% by weight or below 8% by weight, based on the dry matter.
  • the xylan content is above 84% by weight of DM or even above 86% by weight of DM.
  • the glucan content is below 6% by weight of DM or even below 4% by weight of DM.
  • All examples B1 to B4 have a ⁇ -hemicellulose content of over 85% by weight, based on the dry matter.
  • Table 3 shows the specifications and analysis results of comparative examples C1 to C3 available on the market:
  • C1 is a xylan beech wood composition available from Symrise Bioactives AG, acquired in July 201 1.
  • C2 is also a beech wood made xylan composition available from RCMDT GmbH, Germany, acquired in October 2017.
  • C3 is another beechwood made xylan composition from Megazyme uc, Ireland, acquired in March 2018. Table 3: Specifications of Comparative Examples C1 to C3.
  • the comparative examples C1 to C3 all show a xylan content of less than 80 wt .-% based on the dry matter. In addition, in all comparative examples C1 to C3, the total content of ⁇ -hemicelluloses is below 85% by weight of DM.
  • the xylan-containing compositions of Examples B1 to B4 according to the invention accordingly show a greatly improved, high purity compared to the xylan-containing compositions on the market, which can be particularly advantageous for medical applications.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Health & Medical Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Organic Chemistry (AREA)
  • Polymers & Plastics (AREA)
  • Medicinal Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Molecular Biology (AREA)
  • Materials Engineering (AREA)
  • Biochemistry (AREA)
  • Engineering & Computer Science (AREA)
  • General Health & Medical Sciences (AREA)
  • Polysaccharides And Polysaccharide Derivatives (AREA)

Abstract

L'invention concerne une composition (1) présentant un xylane, ainsi qu'un procédé (100) de préparation d'une composition (1) présentant un xylane, un acide (4) étant ajouté à une solution alcaline aqueuse (2) présentant des hemicelluloses (3), et un dépôt (6) présentant un xylane étant précipité à partir de la suspension de précipitation (5) ainsi formée. Selon l'invention, afin d'augmenter le rendement du procédé susmentionné, un acide (4) est ajouté en continu à la solution alcaline aqueuse (2) jusqu'à ce que le pH de la suspension de précipitation (5) passe au-dessous de 4, et de façon à ce que la température de la suspension de précipitation (5) pendant la précipitation ne passe pas au-dessous d'une température de précipitation, la température de précipitation étant d'au moins 40 °C. L'invention concerne en outre un procédé de cellulose ou de viscose (200) comprenant un tel procédé (100).
EP19783334.6A 2018-12-11 2019-10-10 Composition présentant un xylane et procédé de préparation d'une composition présentant un xylane Pending EP3894445A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP18211478.5A EP3666798A1 (fr) 2018-12-11 2018-12-11 Composition comportant du xylane et procédé de production d'une composition comportant du xylane
PCT/EP2019/077504 WO2020119979A1 (fr) 2018-12-11 2019-10-10 Composition présentant un xylane et procédé de préparation d'une composition présentant un xylane

Publications (1)

Publication Number Publication Date
EP3894445A1 true EP3894445A1 (fr) 2021-10-20

Family

ID=64949023

Family Applications (2)

Application Number Title Priority Date Filing Date
EP18211478.5A Withdrawn EP3666798A1 (fr) 2018-12-11 2018-12-11 Composition comportant du xylane et procédé de production d'une composition comportant du xylane
EP19783334.6A Pending EP3894445A1 (fr) 2018-12-11 2019-10-10 Composition présentant un xylane et procédé de préparation d'une composition présentant un xylane

Family Applications Before (1)

Application Number Title Priority Date Filing Date
EP18211478.5A Withdrawn EP3666798A1 (fr) 2018-12-11 2018-12-11 Composition comportant du xylane et procédé de production d'une composition comportant du xylane

Country Status (4)

Country Link
EP (2) EP3666798A1 (fr)
CN (1) CN113166278A (fr)
TW (1) TW202031689A (fr)
WO (1) WO2020119979A1 (fr)

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2572731B1 (fr) * 1984-11-07 1987-03-06 Sanofi Sa Nouveaux sulfates de xylanes de bas poids moleculaires, leur procede de preparation et leur activite antithrombotique et hypolipemiante par voie orale
AT503624B1 (de) 2006-05-10 2008-08-15 Chemiefaser Lenzing Ag Verfahren zur herstellung von xylooligosacchariden
CN102409572B (zh) * 2011-09-14 2014-08-13 四川大学 综合分离甘蔗渣中木质纤维素的绿色新工艺
FI126212B (fi) * 2012-03-27 2016-08-15 Upm Kymmene Corp Menetelmä ja järjestelmä ksylaanin eristämiseksi kasvimateriaalista

Also Published As

Publication number Publication date
CN113166278A (zh) 2021-07-23
TW202031689A (zh) 2020-09-01
EP3666798A1 (fr) 2020-06-17
WO2020119979A1 (fr) 2020-06-18

Similar Documents

Publication Publication Date Title
DE2732289C2 (fr)
DE2737118C2 (fr)
EP1366231B1 (fr) Procede permettant de separer les hemicelluloses d'une biomasse contenant des hemicelluloses
DE69731986T2 (de) Zusammensetzung von Nanofibrillen von Cellulose mit carboxylierter Cellulose mit hohem Substitutionsgrad
DE4342442C2 (de) Verfahren zur Herstellung von Level-off DP Cellulose (LODP Cellulose) und ihre Desaggregierung zu mikrokristalliner Cellulose
EP1753908B1 (fr) Procede de production d'une pate chimique
WO1996030411A1 (fr) Procede permettant d'activer des polysaccharides, polysaccharides obtenus selon ledit procede et leur utilisation
EP0120471A2 (fr) Cellulose microfibrillée redispersable
CH638539A5 (de) Verfahren zur gewinnung von xylan und faserstoffen aus xylanhaltigen pflanzlichen rohstoffen.
DE2830476A1 (de) Verfahren zur abtrennbarmachung des lignins von cellulose und hemicellulose in lignocellulosematerial und dadurch gewonnenes lignocelluloseprodukt
DE60204501T2 (de) Verfahren zur Herstellung von Tannin und seine Verwendung
DE1924804A1 (de) Verfahren zur Herstellung von Viskose
WO2020207766A1 (fr) Procédé de récupération d'une solution alcaline, ainsi que procédé pour fabriquer des corps moulés cellulosiques régénérés présentant un tel procédé
EP0003135B1 (fr) Procédé pour améliorer la solubilité de viscose
EP3894445A1 (fr) Composition présentant un xylane et procédé de préparation d'une composition présentant un xylane
EP0873364B1 (fr) Procede de production de derives de cellulose
DE2159863A1 (de) Verfahren, um organische Materialien aus wäßrigen Losungen zu gewinnen
EP0033385B1 (fr) Procédé pour la préparation de viscose
DE2732187C2 (de) Verformbare Celluloselösungen und Verfahren zu ihrer Herstellung
AT413820B (de) Verfahren zur herstellung von cellulosischen formkörpern
WO2019170743A1 (fr) Fibres lyocell exemptes de mannane
WO1997023279A1 (fr) Procede d'epuration d'un liquide pollue par des molecules filiformes
DE102019007165A1 (de) Verfahren zur Herstellung einer cellulosischen Funktionsfaser mit hoher Ionenaustauschkapazität, und cellulosischer Funktionsfaser
DE3133920A1 (de) "verfahren zur verbesserung der viskosefiltration"

Legal Events

Date Code Title Description
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: UNKNOWN

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20210712

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

DAV Request for validation of the european patent (deleted)
DAX Request for extension of the european patent (deleted)
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: EXAMINATION IS IN PROGRESS

17Q First examination report despatched

Effective date: 20231010