Title: Report on availability, price, composition and quality of waste textiles and recycled paperboard Subtitle: D2.2 Author: VTT
@EUtrash2cash www.trash2cash.eu This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 646226
Trash-2-Cash www.trash2cashproject.eu @EUtrash2cash
Deliverable Deliverable title
D2:2 Report on availability, price, composition and quality of waste textiles and recycled paperboard
WP2 WP Leader VTT
Work package
2015-09-30 Number of pages 24
Date of submission
D. lead beneficiary Type Dissemination level
RISE R = Document, report PU = Public
GA 646226 Trash-2-Cash Start Date: 2015-06-01
This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 646226.
Table of Contents Introduction ...................................................................................................................... 2 Waste materials ................................................................................................................ 2 1.1 Pure cotton ..................................................................................................................... 2 1.2 Recycled paperboard fibres ............................................................................................. 3 1.3 Pure polyester ................................................................................................................. 3 1. Mechanical pretreatment ........................................................................................... 4 2. Composition and quality of the raw material .............................................................. 5 1.4 Standard analyses ........................................................................................................... 5 1.5 Monosugar analysis of cotton .......................................................................................... 5 1.6 Molar mass distribution .................................................................................................. 5 1.7 Fourier Transform Infrared Spectroscopy ........................................................................ 6 1.8 Differential Scanning Calorimetry .................................................................................... 6 1.9 Metal content analysis .................................................................................................... 6 1.10 Chlorite pre-treatment removing lignin prior to the limiting viscosity number analysis ... 6 3. Results ....................................................................................................................... 7 1.11 Pretreatment .................................................................................................................. 7 1.12 Price and availability of the waste materials .................................................................... 7 1.13 Chemical composition and macromolecular quality of the raw material .......................... 8 1.13.1 Limiting viscosity number ........................................................................................ 8 1.13.2 Intrinsic viscosity of PET ........................................................................................... 9 1.13.3 Kappa number ......................................................................................................... 9 1.13.4 Fibre composition .................................................................................................. 10 1.13.5 Molar mass distribution (MMD) ............................................................................. 10 1.13.6 Ash content ........................................................................................................... 10 1.13.7 Chemical composition (monosugar, extractives, klason lignin) ............................... 11 1.13.8 DSC ........................................................................................................................ 12 1.13.9 Metal content ........................................................................................................ 13 1.13.10 FTIR .................................................................................................................... 14 4. Summary of the waste materials .............................................................................. 15 5. Appendices ............................................................................................................... 17 1.14 Appendix 1 DSC Thermograms ...................................................................................... 17 1.15 Appendix 2 FTIR spectra ................................................................................................. 3
INTRODUCTION The purpose of the Trash-2-Cash project is to utilize zero-value waste to create high quality products. This report summarizes the availability, price, chemical composition and quality of textile waste and recycled paperboard of the raw material used in the Trash-2-Cash project. These parameters are essential to validate in order to select the right recycling chemical treatment conditions. The textile waste is supplied by the project members and contains pre- and postconsumer textile waste and fibres. In the first hand, the selection criterion has been high volume zero-value waste. When this has not been possible, waste which the recycling processes can handle today or slightly challenging material for the recycling processes have been selection critera.
WASTE MATERIALS The waste material used in the project is pure cotton, pure polyester, cotton and polyester blend, and recycled paper board fibres. Detailed description of the waste materials is described below.
1.1
PURE COTTON
1.1.1.1 PRE-CONSUMER UNCOLORED COTTON FIBRES Pre-consumer uncolored short staple cotton noil fibres (fraction D9, after the comber press) from SÖKTAŞ cotton yarn spinning department was supplied by SÖKTAŞ. 1.1.1.2 PRE-CONSUMER COLORED COTTON PRINTED WITH NON-FIXATED DYES Pre-consumer colored cotton fabrics with non-fixated dyes were supplied by Tekstina. The fabrics contain softening agent (silicon elastomer polyethylene emulsion). See Figure 1 1.1.1.3 PRE-CONSUMER COLORED COTTON PRINTED WITH FIXATED REACTIVE DYES Pre-consumer colored cotton fabrics with fixated reactive dyes were supplied by Tekstina. See Figure 1
1.1.1.4 FIGURE 1. PRE-CONSUMER COLORED COTTON PRINTED WITH NON-FIXATED DYES TO THE LEFT AND PRE-CONSUMER COLORED COTTON PRINTED WITH FIXATED REACTIVE DYES TO THE RIGHT. POST-CONSUMER
COLORED COTTON DENIM GARMENTS Post-consumer colored cotton garments were supplied by SOEX. One batch was pre-shredded at SOEX. The other batch contained handpicked denim garments where buttons and zippers were
removed by hand. The latter batch was shredded at VTT and intended to be a backup material in case the pre-shredded material contains too high metal or impurity content.
1.2
RECYCLED PAPERBOARD FIBRES
1.1.1.5 OLD CORRUGATED PAPER CARDBOARD Old corrugated cardboard fibres were supplied by SCA Obbola. The pulp does not contain any news or magazine paper and is not deinked. The dry substance in the material is 8-10% and the fibres were freezed in order to avoid mould growth during storing. 1.1.1.6 PAPER FIBRE REJECT Reject fibre waste from the production was supplied by SCA Obbola.
1.3
PURE POLYESTER
1.1.1.7 PRE-CONSUMER STAPLE POLYESTER FIBRES FROM POLAR FLEECE PRODUCTION Pre-consumer colored compacted staple polyester fibres, directly collected in a polar fleece company's facilities through several vacuum cleaners attached to the machineries and supplied by Grado Zero Innovation (GZI; see Figure 2). The original fleece is manufactured from r-PET (recycled bottles) and post-production waste fibre yarns. The machinery that produces this type of synthetic 100% PET fabrics collects the waste in cylindrical compressed tube-shaped forms. Different colors of milled fibres are mixed depending on the production. It is possible to find different mixes of natural and synthetic fibres in the supplied material. The material does not need to be shredded.
Figure 2. Staple polyester fibres from polar fleece production.
1.1.1.8 UNCOLORED POLYESTER (PET) YARN Bobbins of uncolored PET yarn were supplied by GZI (see Figure 2). The yarn is not a waste material, but has been included in the project since high purity is necessary for the development of the polyester recycling methods. The PET yarn can be assimilated to scrapped waste material. The material does not need to be shredded.
Figure 3. Polyester yarn bobbins
1.1.1.9 POST-CONSUMER WHITE POLYESTER GARMENTS The waste material was supplied by SOEX. The material was manually selected by reading on the labels. 1.1.1.10 POST-CONSUMER COLORED POLYESTER GARMENTS The waste material was supplied by SOEX and manually selected by reading on the labels. 1.1.1.11 POST-CONSUMER COLORED POLYESTER COTTON BLEND GARMENTS Mixed post-consumer colored polyester cotton garments was supplied by SOEX. The material has been manually selected and contains polyester and cotton with a fraction from 5% polyester up to 60% polyester. The polyester cotton blend was contaminated with 18% of garments containing other blends than cotton polyester. Only the white garments was picked out from the batch, which was approximately 18% (29 kg) of the original waste material. All bottons, zippers, elastic parts were removed by hand prior to shredding. The colored blend was stored and may be used later in the project.
1.
MECHANICAL PRETREATMENT
Shredding was performed on some of the waste materials to get the material more homogeneous. Mechanical fractionation was performed on the old corrugated paper board fibres using a Dynamic Drainage Jar (DDJ) equipment which composes of a tank with a 200-mesh wire (76 µm) and a mixer. Fines and inorganic materials could be removed by this DDJ fractionation. Materials shredded by SOEX: • Post-consumer shredded cotton denim garments (SOEX) Materials shredded at VTT (Kamas BAHS 30 hammer mill using a 10 mm screen): • Pre-consumer uncolored cotton fibres (SÖKTAŞ) • Pre-consumer colored cotton printed with non-fixated dyes (Tekstina) • Pre-consumer colored cotton printed with fixated reactive dyes (Tekstina) • Post-consumer cotton denim garments, handpicked by SP (SOEX) Materials to be shredded at other facility:
• • •
Post-consumer white polyester garments (SOEX) Post-consumer colored polyester garments (SOEX) Post-consumer white polyester cotton blend garments (SOEX)
Materials to be mechanically fractionated: • Old corrugated paperboard fibres (SCA Obbola) • Paper fibre reject waste from the production (SCA Obbola)
2.
COMPOSITION AND QUALITY OF THE RAW MATERIAL
The composition and quality of the raw materials have been analysed by chemical characterization methods. The analyses are described in more detail below.
1.4
STANDARD ANALYSES
Kappa number Limiting viscosity number (cotton and paperboard) Intrinsic viscosity of PET Carbohydrate composition on paper board Acid-insoluble and soluble lignin (Klason) Extractives, acetone Extractives (wax and fats), petroleum ether Elastan content Cotton/Polyester content Remove protein fibres from other fibres Ash-content (at 550°C) Fibre composition
1.5
ISO 302:2004 ISO 5351:2010 ASTM D4603 SCAN CM 71:09 (acid hydrolysis) modified TAPPI T 222 om-00 SCAN-CM 49:03 (wood pulp, paperboard) ISO 1833-1:2010 (cotton) ISO 1833-20:2010 ISO 1833-11:2010 ISO_1833-4:2010 EN 14775 ISO 9184 + Fibre Atlas1
MONOSUGAR ANALYSIS OF COTTON
Glucose content in the cotton samples was determined by a colorimetric method. Standard deviation of the colorimetric method was 4% for the pre-consumer samples and 10% for the postconsumer sample . GC-MS was used to identify the monosugars in the cotton samples.
1.6
MOLAR MASS DISTRIBUTION
The molar mass distributions (expressed as peak molar mass, Mp, number-average molar mass, Mn, weight-average molar mass, Mw, and polydispersity, PD) were determined by size exclusion chromatography (SEC) using a 0,5% lithium chloride/N,N-dimethylacetamide (LiCl/DMAc) mobile phase and pullulan standards. Prior to SEC characterization, the treated pulps were dissolved and derivatized. Fifteen to twenty-five milligrams of samples were swelled in 15 ml deionized water for 1 day at 23 °C. The solvent was then changed by adding 15 mL of DMAc three times. To the sample 1.9 ml of 8% LiCl / DMAc and 3 mmol of the derivatizing agent ethylisocyanate were added and left with mild stirring for 5 days at freezing temperature. Finally, the samples were diluted to 0.5% LiCl by 1
Ilvessalo-Pfäffi Marja-Sisko, Fiber Atlas – Identification of papermaking fibres, Springer, 1995.
addition of 27.4 ml of DMAc. The excess amount of derivatizing agent was quenched by addition of methanol. The sample was then aggregated by a Retsch MM-2 vibration mill for 30 min followed by filtration using a 0.45 µm PTFE poly (tetrafluorethylene) filter prior to the chromatographic analysis. Samples were analysed on a Waters GPC system using Empower GPC software system. The separations were performed at 80 °C with 0.5% LiCl/DMAc at a flow rate of 0.36 mL min−1 on five Mixed-A 20 μm columns (7.5 × 300 mm, Polymer Laboratories) connected in series. The molar mass distribution analysis was performed by Innventia AB.
1.7
FOURIER TRANSFORM INFRARED SPECTROSCOPY
Attenuated Total Reflection-Fourier Transform Infrared Spectroscopy (ATR-FTIR) was used to analyse cotton, polyester and old corrugated paper board. All measurements were performed in air at room temperature using ten samples of each material. Some selected typical spectra for each material were then presented in Appendix 2. The equipment used was a Perkin-Elmer Spectrum 2000 FT-IR equipped with a MKII Golden Gate, Single Reflection ATR System from Specac Ltd., London, U.K. The ATR crystal was a MKII heated Diamond 45° ATR Top Plate. The measurement range was 4000-650 cm-1 and the curves were not normalised due to lack of stable reference wavelengths.
1.8
DIFFERENTIAL SCANNING CALORIMETRY
The DSC analyses were performed on a Mettler DSC 1 instrument (heat-flux DSC, Mettler Toledo) equipped with a gas controller and a sample robot. The temperature and heat-flow accuracy of the DSC are frequently checked using pure Indium and Zinc as reference materials. Small pieces of sample (2-7 mg) were taken from each waste sample. Each sample was measured once except for the PET bobbin sample that was measured twice. The temperature program was based on ISO standard 11357-3 and included heating the samples to a temperature higher than the melting temperature, Tm, (in order to erase the thermal history), then cooling the samples to a temperature lower than the expected glass transition temperature (Tg) and a second heating where the Tg, Tm and crystallinity was measured. A heating, and cooling, rate of 20°C /min was used and all samples were analysed using an inert atmosphere (N2). The detailed temperature program is shown in the graphs in Appendix 1. The crystallinity data is calculated using a value of heat of fusion for PET (∆h100% ) of 145 J/g.
1.9
METAL CONTENT ANALYSIS
The metals to analysed by ICP-MS were: Al, Si, Fe, Mn, Ti, Mg, Ca, Ba, Na, K, P, As, Cd, Co, Cr, Cu, Ni, Pb, V, Zn and Mo.
1.10 CHLORITE PRE-TREATMENT REMOVING LIGNIN PRIOR TO THE LIMITING VISCOSITY NUMBER ANALYSIS The lignin amount in board can affect the limiting viscosity number. A chlorite treatment was performed to remove the lignin prior to the viscosity number analysis. Five grams of pulp sample was mixed with 170 ml deionized water and heated to approximately 70˚C in a microwave oven. Heated pulp suspension was then moved into a plastic bottle and 2 ml glacial acetic acid was added followed by mixing. Thereafter, 5 g of sodium chlorite and 30 ml of water were mixed together and added into the suspension. The sample was moved to a water bath at 70 ˚C for 5 minutes. The reaction was stopped by first pressing out the liquor followed by washing the sample three times
with 50 g water. The procedure was repeated until the lignin content was sufficient low (measured by kappa number).
3.
RESULTS
1.11 PRETREATMENT Mechanical fractionation of the corrugated paper board fibres using Super DDJ treatment resulted in a yield of 65%. The paper fibre reject waste contained sand and plastics and a fractionation scheme needs to be developed prior to further chemical characterization of the material. Chemical composition data of this material was postponed until a more purified fibre fraction can be obtained.
1.12 PRICE AND AVAILABILITY OF THE WASTE MATERIALS Table 1 shows prices, volumes and description of selection criterias of the waste materials. Table 1. Volumes and prices of the waste materials
Waste materials Pre-consumer uncolored cotton fibres from SĂ–KTAĹž were obtained after the comber press Cotton pre-consumer colored waste from Tekstina
Staple polyester fibres from polar fleece production Uncolored Polyester (PET) yarn
Old corrugated paperboard fibres, SCA Obbola
Availability and Price Monthly production of the waste is approximately 25 000 kg and selling price in Europe is 2.1 $/kg. For this material, selection criteria were based on high waste volume and uncolourness. The specific selected non-fixated and fixated fabrics have no exact price. Tekstina sells pre-consumer mixed cotton textile waste to Italy for 0.03 EUR/Kg. For this material, selection critera was colored cotton with low price.
Zero-value waste material with no market and therefore an important selection critera. No price since there is no market. This is not a real waste material but needed for the development of the depolymerisation of the polyester method. The old corrugated fibres is not a zero-value waste, but was chosen to secure spun fiber and thereby high value products of the T2C project. The total cost for recovered paper board grades depends largely on the transportation cost. It is not always the the best quality has the highest price. The average annual cost for SCA Obbola in 2014 for the recovered paper grades was 1335 SEK/tonne. The average annual cost, to date is 1390 SEK/tonne. During the past five years, the highest cost for SCA Obbola was 2085
Paper fibre reject from the production, SCA Obbola Post-consumer pre-shredded cotton denim, SOEX Post-consumer white polyester garments, SOEX
Post-consumer colored polyester garments, SOEX
Polyester cotton blend garments, SOEX
SEK/tonne in April 2011 when they bought when they bought corrugated fibreboard from UK (grade 1.05 which is old corrugated containers). The top quality of recovered paper grades according to SCA Obbola is new shavings of corrugated fibreboard (4.01, clippings) and the price peaked in May 2011 with a price of 1968 SEK/tonne, delivered from The Netherlands. The lowest quality is for local deliverables of 1.05 corrugated fibreboard reached the lowest value at 696 SEK/tonne in September 2014. The fibres is a zero-value waste and it costs 34 ₏/tonne pays SCA Obbola to get rid of it. The post-consumer denim ‌to be reported Pure polyester is a criterion for the polyester recycling processes. The specific selected mix has no exact price and market. It was difficult to obtain high amount of this fraction due to that polyester is often mixed with other fibres. Pure polyester is a criterion for the polyester recycling processes. The specific selected mix has no exact price and market. It was difficult to obtain high amount of this fraction due to that polyester is often mixed with other fibres. The specific selected mix has no exact price and market. The difficulty to obtain 50:50 polyester:cotton of this fraction is overcomed by mixing 50 % of high polyester:low cotton content with 50 % of low polyester: high cotton content. However most of the clothes containing polyester and cotton have a polyester content of 20-30%. The final polyester/cotton ratio was estimated to 35%/65%.
1.13 CHEMICAL COMPOSITION QUALITY OF THE RAW MATERIAL
AND
MACROMOLECULAR
The results from the analyses are presented separately below.
1.13.1 LIMITING VISCOSITY NUMBER The limiting viscosity numbers of the cotton samples, measured by SP and VTT, are shown in Table 2. Table 2. Limiting viscosity number of cotton and paper board samples Waste material
Limiting viscosity number, ml/g SP
VTT
Pre-consumer uncolored cotton (shredded at VTT), SÖKTAŞ
2030±110 1
Pre-consumer colored cotton printed with non-fixated dyes (shredded), Tekstina
900±32
Pre-consumer colored cotton printed with fixatedrea ctive dyes (shredded), Tekstina
1000±37
Post-consumer pre-shredded cotton denim, SOEX Post-consumer cotton denim, SOEX (shredded at VTT)
1120±19
Old corrugated paperboard fibres after Super DDJ fractionation, SCA Obbola
1890±172 1
860±37
1
970±8
1200±55
2
910±19
2
930±36
630±66 2 750±7
1
1 1
670±6 3 740±21
1
Filtered (Polyamide wire 45 µm (SP)) Filtered and corrected by weight of the dissolved fraction 3 After chlorite delignification 2
The cotton samples from Tekstina contained small amounts of undissolved particles after the dissolution. These particles only marginally affected the viscosity number by approximately 10 units. Divergent results were obtained of the post-consumer cotton denim samples from SOEX. SP obtained an undissolved residual fraction of 26 wt% of the pre-shredded post-consumer cotton denim sample and 10 wt% of the VTT-shredded sample, whereas VTT did not obtain any undissolved fraction for any of those samples. The old corrugated paperboard fibres were mixed in water and copperethylendiamine (CED) according to the standard. Longer mixing and CED-treatment time was necessary for the cotton samples. Samples performed by VTT were analysed after 1h water mixing followed by 3h CED treatment, whereas samples performed by SP were analysed after 30 min water mixing followed by CED treatment overnight (16 h).
1.13.2 INTRINSIC VISCOSITY OF PET The polyester PET bobbin sample was successfully dissolved in 60/40 phenol/1,1,2,2 tetrachloroethane at a temperature of 110 °C. Dissolution test was performed on the original mix pre-consumer polyester (PET) from polar fleece production. The original mix PET was not completely dissolved in phenol/1,1,2,2 tetrachloroethane. The FTIR spectra of the original mix PET polar fleece revealed wool as a component in the material. An alkaline hypochlorite solution according to ISO_1833-4_2010 was used to remove the wool fibres. The mixed colored wool-free PET polar fleece was then easily dissolved in 60/40 phenol/1,1,2,2 tetrachloroethane. The intrinsic viscosity numbers measured at a PET concentration of 0.5% at 30°C are presented in Table 3. Table 3: Intrinsic viscosity of polyester (PET) samples.
Polyester sample name PET bobbin Mixed colored PET polar fleece (wool –free)
IV(30°C, 0,5%) 0.60±0.03 0.57
1.13.3 KAPPA NUMBER Kappa number is a measurement of a standard potassium permanganate solution that a pulp will consume and ranges from 1-100. A high lignin content results in a high kappa number. The kappa number of the old corrugated paperboard fibre sample after Super DDJ filtration was 55.8.
1.13.4 FIBRE COMPOSITION Old corrugated paperboard fibres consist of different raw materials manufactured in different pulping processes. The old corrugated paperboard after Super DDJ filtration consisted of 14% chemical softwood, 19% chemical hardwood, 61% mechanical softwood and 6% semi-chemical hardwood fibres.
1.13.5 MOLAR MASS DISTRIBUTION (MMD) Table 4 and Figure 4 show the molar mass distribution of the cotton and paperboard samples. Table 4. Molar mass distribution of cotton and paper board samples Sample
Analysis no.
Pre-consumer uncolored cotton (shredded), SĂ–KTAĹž Pre-consumer colored cotton printed with non-fixated dyes (shredded), Tekstina Pre-consumer colored cotton printed with fixated-reactive dyes (shredded), Tekstina Post-consumer pre-shredded cotton denim, SOEX Old corrugated paperboard fibres after Super DDJ fractionation, SCA Obbola
1 2 1 2
Mp (g/mol) 1123714 1076862
Mn (g/mol) 287921 349719
Mw (g/mol) 1 2349633 688455 705112
1 2
890162 913071
200531 607441 180713 603516
919629 1106011 3.03 918514 1105412 3.34
1 2 1 Cellulose 2 Hemicellulose 1 Cellulose 2 Hemicellulose
681494 666636 1058756 38125 1202803 39745
348426 342153 344381 24364 368606 24705
902277 881758 944460 46577 947947 52241
634042 606783 650614 36067 662931 38976
Mz (g/mol) 968393 972557
Mz+1 (g/mol) 1136034 1137720
1088120 1081717 1130841 54485 1132537 62182
PD (-) 2.39 2.02
1.82 1.77 1.89 1.48 1.80 1.58
1
The software calculation programme was not able to quantify the integral of the peak. The Mw value was obtained from the calibration curve (lg Mw = 12.8-0.3T) at a retention time of 21.43 min.
Figure 4. Molar mass distribution of cotton and paper board samples. (Comment: Bad resolution. We are waiting for better resolution from Innventia)
1.13.6 ASH CONTENT Table 4 shows the ash content.
Table 4. Ash content by dry weight Sample
Ash content (at 550 °C) wt%
Pre-consumer uncolored cotton (shredded at VTT), SÖKTAŞ
1.6
Pre-consumer colored cotton printed with non-fixated dyes (shredded at VTT), Tekstina
1.7
Pre-consumer colored cotton printed with fixated-reactive dyes (shredded at VTT), Tekstina
0.3
Post-consumer shredded cotton denim, SOEX
1.1
Post-consumer cotton denim, SOEX (shredded at VTT)
-
Old corrugated paperboard fibres after Super DDJ filtration
2.8
Post-consumer white PES/COT garments from SOEX (shredded at VTT)
0.7
Uncolored Polyester (PET) yarn
<0.2
Colored polyester (PET) staple fibres from polar fleece production
1. Original mixed 2. Mix of red, black and red-black
0.5 0.4
1.13.7 CHEMICAL COMPOSITION (MONOSUGAR, EXTRACTIVES, KLASON LIGNIN) The glucose content of the cotton samples was determined by a colorimetric method and the numbers are shown for the cotton samples in Table 5. Table 5. Glucose content in the cotton samples Sample Pre-consumer uncolored cotton (shredded), SÖKTAŞ Pre-consumer colored cotton printed with non-fixated dyes (shredded), Tekstina Pre-consumer colored cotton printed with fixated-reactive dyes (shredded), Tekstina Post-consumer pre-shredded cotton denim, SOEX
Glucose content, % 64 100 97 69
The glucose content in the uncolored cotton sample unexpectedly low and the data needs to be confirmed by a second method. Extractive analysis with petroleum ether was performed on the pre-consumer uncolored cotton fibres from SÖKTAŞ. The extractive content was 0.6%. The post-consumer pre-shredded cotton denim was extracted with DMAc which is a solvent to remove elastan according to standard ISO 1833-20:2010 and 3.3 wt% was extracted with DMAc. The DMAc solution after extraction was strongly dark blue colored which suggests that color also was
removed. It is therefore difficult to get an understanding how much of the 3.3% that is elastan or if all the extracted content is dye. The post-consumer cotton denim sample contained polyester threads. The relative cotton and polyester content was analysed according to ISO 1833-11:2010 on the DMAc-extracted substrate. The relative cotton content was 83.9% and the relative polyester content was 16.1%. Table 6 shows the chemical composition of the old corrugated paperboard. Table 6. Chemical composition of the old corrugated paper board after Super DDJ filtration. Content Old corrugated paperboard Extractives (acetone), % 0.27 Insoluble lignin, % 11.4 Acid soluble lignin, % 0.6 Total lignin, % 12.0 Arabinose, % 0.8 Galactose, % 0.8 Glucose, % 78.9 Xylose, % 13.3 Mannose, % 6.3 Total carbohydrates, % 86.7
1.13.8 DSC Uncolored polyester (PET) yarn and colored polyester (PET) staple fibres from polar fleece production were analysed by DSC. The polar fleece polyester is a mixture of different colors. The chosen samples for analysis were: original mix, red color, black color, red-black color and white yarn threads. The colored PET samples contained white threads which were removed and analysed separately from the colored PET samples in order to identify the origin of the threads. The original mixed sample represents the supplied material mixed by hand, followed by cryo-milling. The separate color PET samples were taken out by hand from the compacted staple fibres in the nonmixed cylindrical compressed tube-shaped material. All analysed samples seemed to contain PET exhibiting a melting temperature of approximately 255 °C (and Tg at approximately 75-82 °C) except for the ”white threads” sample where a substantial weight loss was achieved and a vague signal was shown . This makes it difficult to evaluate the result from the ”white threads” sample. No other melting peaks (in addition to the PET peak) were noticed during the second heating period. DSC analysis was also performed on the undissolved residue of the post-consumer shredded cotton denim from SOEX after treatment with CED solution according to the limiting viscosity number analysis. The undissolved residue seemed to consist of three different parts: black threads, white threads and grey fluffy fibres. Both the black and white threads seemed to contain PET, whereas the grey fluffy fibres also contained a minor endotherm peak at a temperature of approximately 24 °C. Some of the analysed samples lost a greater weight amount (> 5%) during the analysis, which could be due to evaporation (e.g. moisture) or a discharge of degradation products. For example, the
“original mix” polar fleece sample lost -5.7%, “white threads” lost -32.1% and the undissolved grey fluffy fibres lost -9.6%. A rough estimation of the PET content was performed on the analysed samples by comparing the crystallinity of the polymers compared to the PET bobbin sample. The PET bobbin sample was used as a reference for the estimation since the bobbin sample seemed to be pure PET in the DSC thermogram. All the crystallinity numbers were obtained after correction of the weight loss. Note, that the estimation is based on the assumption that the PET samples have the same crystallinity as the pure PET bobbin sample (approximately 37%). Samples containing high content of pigment and fillers may contribute to a lower PET content. The result from the estimation of the PET content indicated varied PET content of the different samples (88-99%), where the two samples ”white threads” and ”undissolved fluffy grey fibres probably to a larger extent contain other fibres than PET. To be noted, the estimations were based on only one measurement of each material (except for the uncolored bobbin). The content and additives (fillers, pigments) could affect the results. Detailed data and thermograms can be seen in Appendix 1.
1.13.9 METAL CONTENT All the samples were analysed by its metal content and shown in Table 5. Table 5. Metal content by ICO-OES expressed as weight percentage on dry base and on ashed sample at 550 °C. Metal
Al Si Fe Ti Mn Mg Ca Ba Na K P As Cd Co Cr Cu Mo Ni Pb V Zn
Uncolored cotton mg/kg
Dry On base ashed 21 1115 41 2194 19 1005 <10 <500 <10 <500 724 38812 772 41390 <10 <500 171 9156 5417 290379 285 15275 <0.4 <20 <0.02 <1 <0.1 <3 1 47 1 52 <0.2 <10 0 18 0 16 0 2 4 190
Printed colored cotton with fixatedreactive dyes mg/kg Dry base 97 189 11 3000 <10 63 149 <10 3273 105 82 0 <0.02 4 28 71 <0.2 0 0 1 1
On ashed 6343 12362 725 1 ~20000 <500 41199 97441 <500 213874 6882 5382 29 <1 240 1800 4600 <10 19 13 41 82
Printed colored cotton with nonfixated dyes mg/kg Dry base 22 676 <10 128 <10 37 66 <10 687 21 11 <0.2 <0.02 0 3 4 <0.2 0 0 0 1
On ashed 6012 186658 2138 35240 <500 10253 18160 <500 189621 5822 3173 <20 <1 45 960 1100 <10 35 38 10 250
Pre-shredded cotton denim, mg/kg
Dry base 459 857 87 311 <10 183 2042 32 299 123 137 <0.5 0 1 51 21 <0.2 1 2 0 28
On ashed 41385 77225 7868 28047 <500 16467 184091 2863 26923 11069 12362 <20 5 83 4600 1900 <10 79 150 28 2600
Old corrugated paperboard fibres after Super DDJ filtration mg/kg Dry On ashed base 1937 68757 2248 79795 297 10548 113 4006 <10 476 273 9694 6654 236231 14 506 29 1035 91 3228 37 1321 <0.6 <20 0 1 0 17 3 110 10 370 <0.3 <10 3 96 3 110 1 29 16 580
1
The Titan was precipitated and the value was obtained on the precipitate.
PET bobbin mg/kg
Al Si Fe Ti Mn Mg Ca Ba Na K P As Cd Co Cr Cu Mo Ni Pb V Zn
Dry base 15 <30 6 2 90 3 30 <2 40 20 60 <1 <1 <1 <1 <1 <1 <1 <1 <1 <1
On ashed
Pes-consumer PET polar fleece mg/kg Dry On base ashed 14 3530 138 35180 28 7211 10000 35000 <10 <500 <10 1887 107 27328 <10 <500 79 20216 20 5035 11 2750 0.2 43 0.02 5 2 490 10 2600 1 300 0.1 24 <0.1 <5 1 350 0,4 91 10 2600
1.13.10
Post-consumer white PES garments mg/kg Dry On base ashed 355 51471 625 90524 30 4283 732 105970 <10 <500 127 18451 1092 158186 <10 571 185 26783 61 8900 146 21076 <0.2 <20 <0.02 2 2.8 410 0.6 86 0.7 98 0.1 12 0.2 35 0.6 94 0.3 51 6.6 950
Dry base
On ashed
Dry base
On ashed
FTIR
FTIR is useful analysis for identifying chemical structures of the polymers and to see impurities of the materials. Table 6 lists relevant characteristic band frequencies. For comparison, reference spectra of different textile materials reported in a master thesis was used2. The FTIR spectrum of the cotton uncolored cotton fibres from SÖKTAŞ seemed to exclusively contain cotton fibres. The colored cotton printed with non-fixated dyes from Tekstina was also fairly homogenous and differed from SÖKTAŞ cotton only by a small unidentified peak at approximately 1740 cm-1. The spectrum of the pre-consumer colored cotton printed with fixated-reactive dyes from Tekstina was similar to the other material from Tekstina. The post-consumer colored cotton garments supplied by SOEX showed a slightly less homogenous sample but judging by its characteristic peaks it still contained a considerable amount of cotton fibres. Parts of the material did, however, not dissolve in CED solution, according to the limiting viscosity number analysis, and this undissolved residue showed a different chemical composition, more like polyester with a characteristic peak at approximately 1700 cm-1 (C=O stretch). This is likely residues from thread and labels of the garments, and smaller amounts of this material is also visible in some spectra of the full blend. This indicates that the postconsumer colored cotton garments from SOEX are not 100 % pure cotton. 2
Pettersson Anna, Towards Recycling of Textile Fibers, Separation and characterization of textile fibers and blend, Master Thesis report, Chalmers University of Technology, 2015.
Table 6. List of characteristic band frequencies in FTIR spectroscopy. -1
BAND FREQUENCY (CM ) TYPE OF VIBRATION
FIBRE TYPE
3700-3200
O-H stretch (free and bonded)
Cellulosics
3500-3200
N-H stretch
Polyamides, elastane
2930-2840
C-H stretch
Most fibrous polymers
2260-2240
Câ&#x2030;ĄN stretch (saturated nitrile)
Acrylics
1740-1715
C=O stretch (ester)
Polyesters, acrylics
1670-1630
C=O stretch (amide)
Polyamide, wool
1650-1590
N-H deform (primary amine)
Wool, polyamide
1570-1515
N-H deform (secondary amine) Wool, polyamide
1250-1150
C-O stretch (ester)
Polyester, acrylic
1100-1000
C-O stretch (alcohols)
Cellulosics
730-650
C-H (aromatic)
Polyester
The polyester materials analysed where the two received from GZI, uncolored polyester yarn and pre-consumer staple polyester fibres from polar fleece production. The former showed a high degree of homogeneity with all spectra showing the same appearance, typical for polyester. The preconsumer staple polyester fibres from polar fleece production consisted of red, black and redblack fibres which were analysed separately. The three differently colored materials showed similar appearances, very much like polyester. However, the material also contained a fair amount of small white thin threads that show a different appearance. This spectrum looked more like the spectra of wool, when studying reference spectra of such material. It is hence likely that this material is polyester with a small fraction of fine white wool threads. The undissolved residue of the old corrugated paper board from the limiting viscosity number analysis was different compared to the corrugated board sample. The corrugated paperboard contained peaks at approximately 3300 cm-1 and 1650 cm-1, arising from O-H stretching and OHbending of water. The former of these two peaks is, however, also characteristic of cellulose as well as other peaks, such as ring and side group vibrations in the phenolic structure of cellulose at 10001100 cm-1. The undissolved residue is similar to the paperboard sample but with smaller peaks at the higher wavenumber and some additional minor differences.
4.
SUMMARY OF THE WASTE MATERIALS
Based on the reported results in this report the delivered cotton samples, old corrugated paperboard fibres and polyester bobbin yarn seems to have a quality suitable for further processing in the project.
5.
APPENDICES
1.14 APPENDIX 1
DSC THERMOGRAMS
Samples name
Sample name in DSC
Polyester (PET) bobbin filament
T2C_PET-ref
Pre-consumer polyester (PET) staple fibres from polar fleece production
T2C_Colored
Post-consumer shredded cotton denim (SOEX) residue after treatment with copper(II)ethylenediamine solution (limiting viscosity analysis)
T2C_PET sample 6 “bad” T2C_white threads T2C_undissolved
1. PET ref sample 2 (knot) 2. T2c PET ref3 (knot) 1. t2c black 1 2. t2c red black 1 3. t2c red 1 1. t2c pet sample “bad” 1 (i.e. “mixed origin”) 1. t2c white threads 1. t2c undissoled fibre black 2. t2c undissolved fibre white 3. t2c undissolved fibre grey
^ex o
T 2C _ PET -r ef
Me t h od : 20 15 -0 9- 24 JEr dt 1, 00 s [ 1] 2 5, 0 °C, 5 , 0 0 min N2 50 , 0 ml/ min [ 2] 2 5, 0. . 290 , 0 °C, 20 , 00 K/ min N2 5 0, 0 ml/ min [ 3] 2 90 , 0 °C, 3, 00 min N2 50 , 0 ml/ min [ 4] 2 90 , 0 . . 0, 0 °C, -2 0, 00 K/ min N2 5 0, 0 ml/ min [ 5] 0 , 0 °C, 5, 00 min N2 5 0, 0 ml/ min [ 6] 0 , 0 . . 2 90, 0 °C, 20, 0 0 K/ min N2 5 0, 0 ml/ min [ 7] 2 90 , 0 . . 10 0, 0 °C, - 2 0, 00 K/ min N2 50 , 0 ml/ min Syn ch ro nizat io n en ab led
25. 09. 2015 15: 13: 40
Ext ra po l. Pe ak 20 2, 85 °C Pe ak Va lu e 12 , 07 mW Pe ak 20 2, 62 °C
Ext ra po l. Pe ak 20 3, 71 °C Pe ak Va lu e 9, 4 0 mW Pe ak 20 3, 15 °C
Sam pl e: PET ref sam pl e 2 (knot), 6, 7110 m g Sam pl e: t2c PET ref 3 (knot), 5, 2380 m g
2 W g ^ -1
Crystallinity I ntegral normalized Onset Peak Endset
25 0
38,60 % -375,66 mJ -55,98 J g^-1 252,89 °C 260,07 °C 266,39 °C
10 0 5
20 0 10
Crystallinity I ntegral normalized Onset Peak Endset
29 0 15
20
39,87 % -302,78 mJ -57,81 J g^-1 252,50 °C 260,28 °C 266,07 °C
20 0
10 0
25
30
0
Glass Transition Onset Midpoint Midpoint ASTM,I EC Delta cp ASTM,I EC
68,04 °C 78,48 °C 78,31 °C 0,114 J g^-1K^-1
Glass Transition Onset Midpoint Midpoint ASTM,I EC Delta cp ASTM,I EC
66,23 °C 77,94 °C 77,95 °C 0,140 J g^-1K^-1
0
35
0
10 0
40
Crystallinity I ntegral normalized Onset Peak Endset
37,54 % -285,14 mJ -54,44 J g^-1 236,68 °C 254,63 °C 262,47 °C
Crystallinity I ntegral normalized Onset Peak Endset
36,59 % -356,06 mJ -53,06 J g^-1 240,02 °C 255,15 °C 263,22 °C
20 0
45
50
55
20 0
°C
60
min
S T AR e SW 10. 00
Lab: M ET T LER ^ex o
T 2C _ C ol ored Extrapol. Peak Peak Value Peak
Method: 2015-09-24 J Er dt 1,00 s [ 1] 25,0 °C, 5,00 min N2 50,0 ml/min [ 2] 25,0..290,0 °C, 20,00 K/ min N2 50,0 ml/min [ 3] 290,0 °C, 3,00 min N2 50,0 ml/min [ 4] 290,0..0,0 °C, -20,00 K/ min N 2 50,0 ml/min [ 5] 0,0 °C, 5,00 min N 2 50,0 ml/ min [ 6] 0,0..290,0 °C, 20,00 K/ min N 2 50,0 ml/min [ 7] 290,0..100,0 °C, -20,00 K/ min N2 50,0 ml/ min Synchronization enabled
25. 09. 2015 15: 29: 50
209,77 °C 13,52 mW 209,04 °C
Sam pl e: t2c black 1, 6, 3370 m g
Extrapol. Peak Peak Value Peak
Crystallinity 37,63 % normalized -54,57 J g^-1 Peak 255,42 °C
Crystallinity 36,11 % normalized -52,36 J g^-1 Peak 251,87 °C
190,78 °C 6,38 mW 190,99 °C
Glass Transition Onset Midpoint Midpoint ASTM,I EC Delta cp ASTM,I EC
65,73 °C 77,30 °C 78,31 °C 0,136 J g^-1K^-1
Sam pl e: t2c red bl ac k 1, 4, 1540 m g Crystallinity 32,22 % normalized -46,72 J g^-1 Peak 252,74 °C
5 W g ^ -1
Crystallinity 36,67 % normalized -53,17 J g^-1 Peak 253,29 °C
Extrapol. Peak Peak Value Peak
Glass Transition Onset Midpoint Midpoint ASTM,I EC Delta cp ASTM,I EC
193,66 °C 9,77 mW 193,49 °C
73,33 °C 81,24 °C 81,81 °C 0,150 J g^-1K^-1
Sam pl e: t2c R ed 1, 5,9660 m g Crystallinity 32,84 % normalized -47,62 J g^-1 Peak 252,88 °C Glass Transition Onset Midpoint Midpoint ASTM,I EC Delta cp ASTM,I EC
Crystallinity 36,67 % normalized -53,18 J g^-1 Peak 255,42 °C
25 0
10 0 5
Lab: M ET T LER
20 0 10
29 0 15
20
20 0 25
10 0 30
0 35
0
0 40
72,63 °C 82,68 °C 82,38 °C 0,136 J g^-1K^-1
10 0 45
20 0 50
55
20 0
°C
60
min
S T AR e SW 10. 00
^ex o
T 2C _ PET s am pl e 6 " bad"
Method: 2015-09-24 J Er dt 1,00 s [ 1] 25,0 °C, 5,00 min N2 50,0 ml/min [ 2] 25,0..290,0 °C, 20,00 K/ min N2 50,0 ml/min [ 3] 290,0 °C, 3,00 min N2 50,0 ml/min [ 4] 290,0..0,0 °C, -20,00 K/ min N 2 50,0 ml/min [ 5] 0,0 °C, 5,00 min N 2 50,0 ml/ min [ 6] 0,0..290,0 °C, 20,00 K/ min N 2 50,0 ml/min [ 7] 290,0..100,0 °C, -20,00 K/ min N2 50,0 ml/ min Synchronization enabled
Extrapol. Peak Peak Value normalized Left Limit Right Limit Peak
25. 09. 2015 16: 03: 00
203,27 °C 10,02 mW 1,54 Wg^-1 208,45 °C 191,33 °C 202,18 °C
Sam pl e: t2c pet sam pl e 6 "bad" 1, 6, 5210 m g 2 W g ^ -1
Crystallinity I ntegral normalized Onset Peak Endset Left Limit Right Limit
25 0
34,39 % -325,18 mJ -49,87 J g^-1 242,95 °C 256,01 °C 264,16 °C 193,24 °C 271,20 °C
10 0 5
Glass Transition Onset Midpoint Midpoint ASTM,I EC Delta cp ASTM,I EC
20 0 10
Crystallinity I ntegral normalized Onset Peak Endset Left Limit Right Limit
29 0 15
69,78 °C 80,93 °C 81,63 °C 96,884e-03 Jg^-1K^-1
20
20 0 25
10 0 30
0
0
35
0 40
10 0 45
20 0 50
55
33,13 % -313,30 mJ -48,05 J g^-1 238,28 °C 254,46 °C 261,31 °C 137,53 °C 275,48 °C
20 0
°C
60
min
S T AR e SW 10. 00
Lab: M ET T LER ^ex o
T 2C _ w hi t e t hreads
25. 09. 2015 15: 47: 02
Ext ra po l. Pe ak 19 5, 42 °C Pe ak Va lu e 1, 1 4 mW n or ma lized 0, 3 1 W g^ - 1 Pe ak 19 5, 39 °C
Sam pl e: t2c whi te threads, 3, 6890 m g
Cr yst allinit y 8, 4 3 % I nt eg ra l - 45 , 1 0 mJ n or ma lized - 12 , 2 3 Jg ^ - 1 On se t 21 9, 36 °C Pe ak 24 4, 66 °C En dset 25 5, 76 °C 1 W g ^ -1
Method: 2015-09-24 J Er dt 1,00 s [ 1] 25,0 °C, 5,00 min N2 50,0 ml/min [ 2] 25,0..290,0 °C, 20,00 K/ min N2 50,0 ml/min [ 3] 290,0 °C, 3,00 min N2 50,0 ml/min [ 4] 290,0..0,0 °C, -20,00 K/ min N 2 50,0 ml/min [ 5] 0,0 °C, 5,00 min N 2 50,0 ml/ min [ 6] 0,0..290,0 °C, 20,00 K/ min N 2 50,0 ml/min [ 7] 290,0..100,0 °C, -20,00 K/ min N2 50,0 ml/ min Synchronization enabled
Sig na l Value - 0, 85 W g ^ - 1 a t 24 0, 29 °C
Sig na l Value - 1, 01 W g ^ - 1 a t 25 4, 15 °C 25 0
10 0 5
Lab: M ET T LER
20 0 10
29 0 15
20
20 0 25
10 0 30
0 35
0
0 40
10 0 45
20 0 50
55
20 0
°C
60
min
S T AR e SW 10. 00
^ex o
T 2C _ undis s olv ed
Method: 2015-09-24 J Er dt 1,00 s [ 1] 25,0 °C, 5,00 min N2 50,0 ml/min [ 2] 25,0..290,0 °C, 20,00 K/ min N2 50,0 ml/min [ 3] 290,0 °C, 3,00 min N2 50,0 ml/min [ 4] 290,0..0,0 °C, -20,00 K/ min N 2 50,0 ml/min [ 5] 0,0 °C, 5,00 min N 2 50,0 ml/ min [ 6] 0,0..290,0 °C, 20,00 K/ min N 2 50,0 ml/min [ 7] 290,0..100,0 °C, -20,00 K/ min N2 50,0 ml/ min Synchronization enabled
Extrapol. Peak Peak Value Peak
25. 09. 2015 15: 42: 31
191,11 °C 3,58 mW 191,18 °C
Sam pl e: t2c undis solv ed fi bre bl ack, 2, 4330 m g
Crystallinity normalized Onset Peak Endset
Crystallinity normalized Onset Peak Endset Extrapol. Peak Peak Value Peak
42,50 % -61,63 J g^-1 247,98 °C 258,78 °C 264,02 °C
199,03 °C 6,10 mW 198,65 °C
Glass Transition Onset Midpoint Midpoint ASTM,I EC Delta cp ASTM,I EC
34,60 % -50,18 J g^-1 240,65 °C 254,52 °C 261,77 °C
71,01 °C 82,61 °C 82,71 °C 0,157 J g^-1K^-1
Sam pl e: t2c undis solv ed fi bre white, 3, 7190 m g 5 W g ^ -1
Crystallinity normalized Onset Peak Endset
Glass Transition Onset Midpoint Midpoint ASTM,I EC Delta cp ASTM,I EC
36,36 % -52,73 J g^-1 244,18 °C 251,66 °C 261,97 °C Extrapol. Peak Peak Value Peak
65,25 °C 73,91 °C 75,57 °C 96,384e-03 Jg^-1K^-1
Crystallinity normalized Onset Peak Endset
32,13 % -46,59 J g^-1 238,37 °C 253,44 °C 261,12 °C
194,34 °C 2,31 mW 193,45 °C
Sam pl e: t2c undis solv ed fi bre grey, 2, 2640 m g Extrapol. Peak Peak Value Peak
Crystallinity normalized Onset Peak Endset
25 0
10 0 5
Lab: M ET T LER
Glass Transition Onset Midpoint Midpoint ASTM,I EC Delta cp ASTM,I EC
22,90 % -33,20 J g^-1 243,37 °C 254,22 °C 261,20 °C
20 0 10
29 0 15
3,83 °C -0,39 mW 23,66 °C
20
20 0 25
10 0 30
0 35
0
0 40
10 0 45
Crystallinity normalized Onset Peak Endset
69,74 °C 79,35 °C 80,09 °C 61,980e-03 Jg^-1K^-1
20 0 50
55
15,35 % -22,26 J g^-1 240,91 °C 253,92 °C 260,47 °C
20 0
°C
60
min
S T AR e SW 10. 00
D2.2: Report on availability, price, composition and quality of waste textiles and recycled paperboard
DSC- analysis ( SP) All mass in mg
Crystallinity
37,23
Based on initial sample
Based on final sample
Estimati on!
peak
AST M
peak
msample_after
%mass loss
X [%], initial
X [%], mass comp.
%PET
Tm [°C]
Tc [°C]
Tg [°C]
0,068
6,643
1,0
36,96
37,34
100,3
255, 15
202, 62
78, 31
54,738
0,064
5,174
1,2
36,67
37,12
99,7
254, 63
203, 15
77, 95
0,001
56,327
0,369
6,152
5,7
35,12
94,3
254, 46
202, 18
81, 63
55,58
-0,049
55,483
0,097
5,869
1,6
32,84
33,38
89,7
252, 88
193, 49
82, 28
6,337
56,186
0,002
56,066
0,12
6,217
1,9
36,11
36,81
98,9
251, 87
209, 04
78, 31
4,154
54,198
0,002
54,129
0,069
4,085
1,7
32,22
32,76
88,0
252, 74
190, 99
81, 81
Sample
Pos
m(pan+cap)
msample
mtot
(control)
mafter
PET_ref_2 (knot)
111
49,644
6,711
56,36
0,005
56,292
PET_ref_3 (knot)
120
49,559
5,238
54,802
0,005
"T2C" PET sample 6"bad"
112
50,174
6,521
56,696
Red
113
49,663
5,966
Black
114
49,847
Red-black
115
50,042
mloss
33,13
white threads
116
49,35
3,689
53,034
-0,005
51,851
1,183
2,506
32,1
8,43
12,41
33,3
244, 66
195, 39
n.d.
undissolved fibre_black
117
49,855
2,433
52,29
0,002
52,253
0,037
2,396
1,5
34,6
35,13
94,4
254, 52
191, 18
82, 71
undissolved fibre_grey
118
49,731
2,264
51,996
0,001
51,779
0,217
2,047
9,6
15,35
16,98
45,6 253,
193,
80,
1
undissolved fibre_white
119
50,146
3,719
53,823
-0,042
53,708
0,115
2
3,604
3,1
32,13
33,16
89,1
62
45
09
253, 44
198, 65
75, 57
D2.2: Report on availability, price, composition and quality of waste textiles and recycled paperboard
1.15 APPENDIX 2
FTIR SPECTRA
3
4
5
6