EP4479462A1 - Herstellung von zellstoff aus baumwolle oder baumwollgemischen - Google Patents
Herstellung von zellstoff aus baumwolle oder baumwollgemischenInfo
- Publication number
- EP4479462A1 EP4479462A1 EP23717396.8A EP23717396A EP4479462A1 EP 4479462 A1 EP4479462 A1 EP 4479462A1 EP 23717396 A EP23717396 A EP 23717396A EP 4479462 A1 EP4479462 A1 EP 4479462A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- cotton
- cellulose
- production
- polymerization
- reaction
- 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
Links
Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21B—FIBROUS RAW MATERIALS OR THEIR MECHANICAL TREATMENT
- D21B1/00—Fibrous raw materials or their mechanical treatment
- D21B1/02—Pretreatment of the raw materials by chemical or physical means
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J11/00—Recovery or working-up of waste materials
- C08J11/04—Recovery or working-up of waste materials of polymers
- C08J11/10—Recovery or working-up of waste materials of polymers by chemically breaking down the molecular chains of polymers or breaking of crosslinks, e.g. devulcanisation
- C08J11/14—Recovery or working-up of waste materials of polymers by chemically breaking down the molecular chains of polymers or breaking of crosslinks, e.g. devulcanisation by treatment with steam or water
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L1/00—Compositions of cellulose, modified cellulose or cellulose derivatives
- C08L1/02—Cellulose; Modified cellulose
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21B—FIBROUS RAW MATERIALS OR THEIR MECHANICAL TREATMENT
- D21B1/00—Fibrous raw materials or their mechanical treatment
- D21B1/04—Fibrous raw materials or their mechanical treatment by dividing raw materials into small particles, e.g. fibres
-
- 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
- D21C1/00—Pretreatment of the finely-divided materials before digesting
-
- 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
-
- 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
- D21C5/00—Other processes for obtaining cellulose, e.g. cooking cotton linters ; Processes characterised by the choice of cellulose-containing starting materials
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H13/00—Pulp or paper, comprising synthetic cellulose or non-cellulose fibres or web-forming material
- D21H13/02—Synthetic cellulose fibres
- D21H13/08—Synthetic cellulose fibres from regenerated cellulose
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2301/00—Characterised by the use of cellulose, modified cellulose or cellulose derivatives
- C08J2301/02—Cellulose; Modified cellulose
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2367/00—Characterised by the use of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Derivatives of such polymers
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2367/00—Characterised by the use of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Derivatives of such polymers
- C08J2367/02—Polyesters derived from dicarboxylic acids and dihydroxy compounds
- C08J2367/03—Polyesters derived from dicarboxylic acids and dihydroxy compounds the dicarboxylic acids and dihydroxy compounds having the hydroxy and the carboxyl groups directly linked to aromatic rings
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21B—FIBROUS RAW MATERIALS OR THEIR MECHANICAL TREATMENT
- D21B1/00—Fibrous raw materials or their mechanical treatment
- D21B1/04—Fibrous raw materials or their mechanical treatment by dividing raw materials into small particles, e.g. fibres
- D21B1/12—Fibrous raw materials or their mechanical treatment by dividing raw materials into small particles, e.g. fibres by wet methods, by the use of steam
- D21B1/30—Defibrating by other means
- D21B1/36—Explosive disintegration by sudden pressure reduction
Definitions
- the present invention relates to the production of pulp from cotton and cotton blends.
- This object is achieved by a process for the production of a cellulose polymer with a cellulose content of at least 90%, preferably 92%, from textile waste material, a starting material being cotton or a mixture of cotton and PET with a fiber length of at most 1 mm in a reactor with subcritical water at a temperature of 130-180 °C and a pressure in a range of 1 - 10 bar for about 1 - 120 min and wherein a cellulosic polymer with an average degree of polymerization (DP), but which can be predetermined, of 300 - 1000 DP, of preferably 450-650 arises.
- the educt can of course also consist of pure cotton.
- the pre-determination of the DP value plays a decisive role here, since the quality of the end materials to be produced is designed for a purity in a specific DP value range. Lyocell is made from pulp with a DP value of 550-600, viscose from pulp with a DP value of 300-700. Flier, the DP constancy in the pulp is a guarantee for the quality of the end product. The present method thus predetermines the DP range of the pulp.
- a cellulose polymer with a degree of purity of 90% - 92% and more is a high-quality starting product which can be used to create a large number of other high-quality products.
- Viscose and lyocell can be mentioned as a production goal. Viscose is normally made from dissolving pulp, which is obtained from various types of wood or cotton. The quality of the cellulose differs from that used for paper production, since cellulose with a certain chain length and purity has to be used here.
- Lyocell fibers are known for their high dry and wet strength, they are soft and absorb moisture very well. The textiles made from this have a "smooth" and "cool” feel with a flowing drape. They are almost wrinkle free and can be washed and dry cleaned.
- the DP values must also be adjusted by the fiber manufacturer for seamless further processing. They should correspond to the fiber-specific requirements and are in a range specified by the fiber manufacturer predefined DP area. Depending on the viscose fiber, this is in a range between 300-700. Pulp for lyocell fibers has a DP of 500-700, better still 550-600.
- the polymer fiber produced in this method according to the invention is therefore an “upcycling” product.
- the fiber length of the starting material of at most one millimeter means here only a previous comminution of the starting material. This allows the subsequent reaction to proceed more easily.
- the fiber length also serves to standardize the process parameters, which must be selected differently for different fiber lengths. We shall come back to this later. It has been shown that the method according to the invention is particularly advantageous for the production of high-purity pulp with a predefined DP, in the range of 300-1000, from textile waste. In a very special embodiment, fiber lengths of the educt in the range from 0.2 mm up to 8 mm are used. The shorter fibers blend better in the water.
- Subcritical water refers to liquid water at temperatures between the atmospheric boiling point, i.e. 100 °C, and the critical temperature, i.e. 374 °C.
- water has special properties that are not otherwise common.
- the ionization constant in this state increases with temperature and is approximately three orders of magnitude higher than that of water in the normal state.
- the dielectric constant decreases from 80 to 20.
- Such a drastic change in physical properties causes a rapid dissolution of cross-linking in the textile waste material, which consists of cotton and PET.
- the treatment of substances in an aqueous system at high temperature and under pressure is called hydrothermal treatment.
- the reactor is thus a hydrothermal reactor.
- the temperature used in the reactor is within a range between 130°C - 200°C or more preferably 160°C - 200°C.
- the pressure is regulated to a range between 1 -25 bar.
- the reaction time is between 1 and 120 minutes. With the set parameters, the reactor can attack the raw material, i.e. the textile waste, at the fiber level and weaken the bonding strength of the fibers to one another or even separate the fiber strands that are lying on one another and interwoven with one another. In the process, any polyester residues that may be present at the same time are also decomposed.
- the degree of polymerization of the products can also be influenced with the aid of the operating parameters which are decisive for the operation of the reactor.
- subcritical water as a solvent is non-toxic, environmentally friendly and inexpensive. It is naturally PH-neutral and therefore non-aggressive as a solvent.
- the product not only has a purity of at least 90% - 92%, but it also has an average degree of polymerization (DP) of 300 - 1000 or even 450-650. If the reaction is very well adjusted, the product even has an average degree of polymerization (DP) of 550-600.
- DP average degree of polymerization
- This degree of polymerization indicates a homogeneous reaction, with the starting material being degraded to such an extent that it can be optimally further processed into lyocell.
- the degree of polymerization indicates the number of basic building blocks per polymer molecule. It is identical to the quotient of the mean molar mass of the polymer and the molar mass of its repeating unit (the monomer unit). The exact number can usually only be an average value for the sample under consideration. This average is referred to as the average degree of polymerization (DP).
- DP average degree of polymerization
- the degree of polymerization of a sample is usually determined via its molar mass.
- the Melt Flow Index method should be mentioned here. So z. B. the viscosity of a plastic melt with increasing degree of polymerization, the mean value can be determined indirectly (ie relative to a chemically comparable standard) using the MFL method.
- the degree of polymerization and the three-dimensional distribution of the monomers in the molecule have a major influence on the physical and especially the mechanical properties of a polymer. According to Staudinger, however, the fiber strength does not change proportionally with the degree of polymerisation.
- the DP is e.g. B. for cotton 3000, viscose fibers 250 - 700, polyamides 100 - 180 and polyester 130 - 220. Determining the average degree of polymerization is of great importance, especially for cellulose fibers, because it allows chemical damage to these fibers to be characterized numerically.
- the cotton/PET mixture consists of a composition with a PET content of up to 5%.
- the foreign fiber portion does not consist of PET but of another fiber. These foreign fibers are also processed without impairing the end product. Tests with a proportion of foreign fibers of up to 5% show no impairment at all of the process and the end product. If it is foreign fibers made of elastane or PES/PET, these disappear in the end product. It also makes no difference whether the fiber mixture contains colored components.
- the educt can have a metal content of the order of >10 ppm. Both small metal residues and large metal contents are reliably removed from the educt.
- the alkaline earth and alkali metals, as well as many heavy metals are responsible for the formation of lumps in the reaction mixture. The clumping can clog the filter and thereby impair the reaction.
- the heavy metals have a catalytic effect and thus cause undesirable side reactions.
- the heavy metals are in the range of less than 10 ppm, the reaction will not be affected.
- the addition of antioxidants can be taught to support high levels of heavy metals.
- the process according to the invention is also not affected by the presence of the starting material in Suspension form affected.
- the method thus allows for the reduction of the cellulosic fibers in the textile waste material, the detachment of the cellulosic fibers from the textile waste material, or both.
- the catalyst-free course of the reaction is important.
- the existing fibers are usually broken down with the help of acids or bases, the DP is adjusted and then further processed.
- the disadvantage of adding this PH-effective substance is that the end product is adversely affected by the aggressive chemicals. These are then removed from the reaction mixture in an additional step, but the damage has already occurred. Of course, the additional cleaning step also causes effort, costs and is very time-consuming. Disposal of the solvent is also complicated by contamination. Therefore, the catalyst-free reaction in the inventive method is an important step in a sustainable, environmentally friendly and, at the reaction temperatures present, also energy-saving procedure for recycling textiles.
- the PH neutralization of the pulp no longer needs to be carried out.
- the pH throughout the process is around 5.0 to 9.0.
- the reaction takes place in subcritical water at temperatures between 130 - 180°C.
- the reaction time is between 1 and 120 minutes and a pressure of 1-25 bar is applied.
- the PH-neutral reaction medium (values of 5 - 7 have been measured here) has a solid/liquid ratio of 1:10 to 1:20. No acids, bases or other catalysts are added.
- the process takes place with the exclusion of oxygen. However, oxygen that is added or admitted in a controlled manner can cause oxidative changes, particularly in the DP value. Furthermore, it has been shown that even smaller applied pressure ratios of up to 1 or 10 bar are sufficient to allow the process to run favorably.
- the length of the educt understandably has an influence on the stirrability of the mixture. This also affects on the reaction. For example, with an educt fiber length of 1 mm and a proportion by weight of 2.5% by weight, the mixture is stirrable, with a proportion by weight of 5% by weight it is difficult to stir and with a proportion by weight of 7.5% by weight it is no longer stirrable.
- the mixture is easily stirrable with a weight proportion of 2.5% by weight, easily stirrable with a weight proportion of 5% by weight and still easy with a weight proportion of 7.5% by weight is touchable.
- the cutting mill used namely the Fritsch, PULVERISETTE 19 universal cutting mill (5000 watts, 400V, 3 ⁇ 50/60Hz, 13Nm, speed: 300-3000rpm, sieve insert size: 0.24mm) has proven to be particularly suitable. However, the use of other cutting mills is also possible.
- Old textiles made of cotton with a PE content of 5% are cut to a fiber length of 1 mm after sorting.
- This relatively short educt length was initially only used in order to be able to compare the many tests or test series with one another.
- the shredding device can be a normal shredder.
- the lengths of the torn and reduced textile waste should be as equal as possible.
- the degree of coloring of the waste is irrelevant. Almost all textile dyes are dissolved out in the ongoing process.
- the presence of the starting materials in the form of a suspension, ie in extremely fine distribution in a liquid, is also not detrimental to the process according to the invention.
- the starting material can have an average degree of polymerization of more than 700 and still work well.
- the higher the degree of polymerization in the starting product the more complicated the depolymerization that takes place in the reaction process.
- average degrees of polymerization of 300 - 1000, usually 450 - 650 or even 550 - 600 are achieved.
- the raw materials were then filled into the high-pressure laboratory reactor type BR-300 called highpreactor from Berghof. With a maximum achievable temperature of 300° C. and a maximum pressure build-up of 200 bar, this reactor is completely sufficient for the present inventive method. Among other things, the following 6 tests were carried out in the reactor.
- the severity factor is a degree of severity coefficient for the subcritical liquid-hot water pretreatment of products, in this case the used textiles.
- Severity factor expressed mathematically, is the integral of the steam temperature or temperature and the exposure time. It is thus a measure of the severity or intensity of the overall reaction conditions in a chemical reaction; in our case the temperature, the pressure. The time and temperature can be read from the table. The reaction pressure is between 1 and 10 bar.
- the solid-liquid ratio was between 1:10 and 1:20 in the tests.
- the otherwise occurring by-products can only be found in small numbers and low concentrations due to the small number of educts. These are some oligomers, glucose, fructose and xylose. The concentration of the substances is negligible and is almost 0 g/L.
- the X-axis shows the temperature/time reaction pair
- the Y-axis shows the degree of polymerization (DP). You can see exactly which parameters can be used to set the DP values.
- the average degree of polymerization was determined according to the relevant DIN standard.
- the viscometer e.g. Ubbelohde
- the viscometer is placed at 25°C (+/- 0.1°C) using a water bath thermostat and
- the cellulose solution is filtered through a glass filter (glass frit Por. 1) before the measurement.
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Health & Medical Sciences (AREA)
- Mechanical Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Development (AREA)
- Wood Science & Technology (AREA)
- Polysaccharides And Polysaccharide Derivatives (AREA)
- Processing Of Solid Wastes (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Paper (AREA)
- Separation, Recovery Or Treatment Of Waste Materials Containing Plastics (AREA)
Abstract
Description
Claims
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE102022000572.7A DE102022000572A1 (de) | 2022-02-15 | 2022-02-15 | Herstellung von Zellstoff aus Baumwollgemisch |
| PCT/DE2023/150006 WO2023155957A1 (de) | 2022-02-15 | 2023-02-13 | Herstellung von zellstoff aus baumwolle oder baumwollgemischen |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| EP4479462A1 true EP4479462A1 (de) | 2024-12-25 |
Family
ID=86051813
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP23717396.8A Pending EP4479462A1 (de) | 2022-02-15 | 2023-02-13 | Herstellung von zellstoff aus baumwolle oder baumwollgemischen |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US20250154719A1 (de) |
| EP (1) | EP4479462A1 (de) |
| JP (1) | JP2025506575A (de) |
| CA (1) | CA3243799A1 (de) |
| DE (2) | DE102022000572A1 (de) |
| WO (1) | WO2023155957A1 (de) |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109467741B (zh) * | 2017-09-08 | 2022-02-11 | 香港纺织及成衣研发中心 | 由有机酸催化的水热反应来分离和回收废旧涤棉纺织品的方法 |
| CN111868316B (zh) * | 2018-01-12 | 2023-09-05 | 希尔科公司 | 从废弃纺织品中回收棉纤维和聚酯纤维的方法 |
| US12305023B2 (en) * | 2019-02-27 | 2025-05-20 | The Hong Kong Research Institute Of Textiles And Apparel Limited | Cellulosic superabsorbent polymer from post-consumer textile waste |
| EP3748074A1 (de) * | 2019-06-04 | 2020-12-09 | Lenzing Aktiengesellschaft | Verfahren zum herstellen eines cellulosischen papierstoffes aus alttextilien |
| EP3748072A1 (de) | 2019-06-04 | 2020-12-09 | Lenzing Aktiengesellschaft | Verfahren zum kontinuierlichen bereitstellen eines cellulose-aufweisenden aufbereiteten ausgangsstoffs |
| AU2020296474A1 (en) * | 2019-06-18 | 2021-12-23 | BlockTexx Labs Pty Ltd | A system and process for the separation and recycling of blended polyester and cotton textiles for re-use |
| WO2020252683A1 (en) * | 2019-06-19 | 2020-12-24 | The Hong Kong Research Institute Of Textiles And Apparel Limited | Method and system for recovering fibers from fibrous products |
-
2022
- 2022-02-15 DE DE102022000572.7A patent/DE102022000572A1/de not_active Withdrawn
-
2023
- 2023-02-13 WO PCT/DE2023/150006 patent/WO2023155957A1/de not_active Ceased
- 2023-02-13 CA CA3243799A patent/CA3243799A1/en active Pending
- 2023-02-13 JP JP2024548532A patent/JP2025506575A/ja active Pending
- 2023-02-13 DE DE112023000938.4T patent/DE112023000938A5/de active Pending
- 2023-02-13 EP EP23717396.8A patent/EP4479462A1/de active Pending
- 2023-02-13 US US18/838,395 patent/US20250154719A1/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| DE102022000572A1 (de) | 2023-08-17 |
| CA3243799A1 (en) | 2025-01-20 |
| JP2025506575A (ja) | 2025-03-12 |
| US20250154719A1 (en) | 2025-05-15 |
| DE112023000938A5 (de) | 2025-03-13 |
| WO2023155957A1 (de) | 2023-08-24 |
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