Research libraryClosing the Loop
Chapter 06 of 14 · Part II · Draft web edition
When cotton fibres are too short for mechanical spinning, chemical recycling dissolves cellulose chains into high-purity pulp for viscose and lyocell filaments, provided degree of polymerisation and solvent recovery are tightly controlled.
The cloth is woven from this chapter's 5 exhibits: each weft is one exhibit's own data, normalised; each warp group is a section. The probe reads the exhibit's own value where it crosses. Procedural visualisation, not a measurement.
Read-out
Chemical process sequence synthesising hydrated choline chloride / lactic acid / water (30% H2O) deep eutectic solvent depolymerisation (S34), sequential acid/alkaline viscosity tuning (S36), and closed-loop solvent recovery and wet-spinning (S34, S35).
Unit: process stage. Status: sourced. Sources: S34, S35, S36.
Overture · 1 min
Chemical cellulosic regeneration solves the physical limit of mechanical textile recycling by operating at the macromolecular scale rather than the staple-fibre scale.[S34][S35] When pre-consumer cotton offcuts, spinning comber noils, carding strips or ginning linters are too short to hold twist in an open-end rotor groove, chemical pre-treatment cleaves and purifies the underlying cellulose chains into dissolving pulp.[S36][S37] Dissolved into a homogenous spinning dope and extruded through precision spinnerets, regenerated man-made cellulosic fibres (MMCFs) such as viscose, modal and lyocell emerge as continuous filaments or uniform staple fibres with virgin-equivalent tenacity and lustre.[S34][S36] Yet chemical regeneration is a continuous process industry governed by strict polymer rheology, trace-metal tolerances below 20 parts per million, and capital thresholds exceeding US$140 million for standalone commercial mills.[S34][S0601] For a greenfield cotton-to-garment venture in Cameroon, the engineering decision is one of disciplined sequencing: use zero-capex shop-floor sorting to capture and grade pure cellulosic residues today, monetise non-spinnable linters and short waste as certified feedstock for existing viscose and lyocell producers in Phases 1 and 2, and defer domestic chemical reactor capital until regional cluster volumes cross commercial breakeven in Phase 3.[R06][R10][S36]
6.1
Related · chapter 056 paragraphs step it
Read-out
Illustrative engineering staple-length bounds across four cotton feedstock categories after five-cylinder mechanical tearing, grounded in Rieter recycling classifications (S0501) and University of Boras tearing mechanics (S0502). Values are not a measured GFT factory result.
Unit: staple length in millimetres (mm). Status: illustrative. Sources: S20, S24, S35, S0501, S0502. Illustrative figures are teaching examples, not measured factory results.
Read this exhibit in its chapter ↗Mechanical garnetting and carding treat the cotton fibre as an intact physical cylinder pulled apart from woven or knitted yarns by saw-tooth pins.[S20][S24] Because every pass over a pinned drum ruptures fibres, mechanical recycling shortens staple length and raises the short-fibre index, imposing a ceiling on yarn fineness and requiring carrier blends of 50 to 80 percent virgin cotton lint in apparel applications.[S20][S24] Chemical cellulosic regeneration bypasses this downcycling ceiling by dissolving the solid cotton fibre into individual poly-(beta-1,4-D-anhydroglucopyranose) chains in solution and precipitating them anew through wet or dry-jet wet spinning.[S34][S35][S36]
In a chemical regeneration line, physical staple length at the reactor inlet has zero bearing on the physical length of the extruded product.[S35][S36] Whether incoming cellulose originates from 28-millimetre virgin ginned lint, 18-millimetre mechanically torn cutting clips, 10-millimetre spinning comber noils, or 4-millimetre cottonseed linters, dissolution erases prior fibre morphology and mechanical surface fibrillation.[S34][S36][S0602] Once purified cellulose pulp is dissolved into an alkaline xanthate viscose dope or a direct solvent such as aqueous N-Methylmorpholine N-oxide (NMMO), ionic liquids, or deep eutectic solvents, metering pumps force the solution through spinneret capillaries measuring 40 to 60 micrometres in diameter.[S34][S35]
As the liquid jets enter the coagulation bath, mass transfer regenerates solid cellulose II crystal structures oriented along the filament axis by godet drawing.[S34][S35] The plant can wind the coagulated strands as continuous multifilament yarns or crimp and cut them to any commercial staple length (such as 38 millimetres for ring spinning).[S35][S36] Chemical regeneration is thus the only industrial route capable of converting zero-twist mill dust, comber noils, and multi-cycled mechanically shortened cotton back into fine shirtings and filament fabrics without sacrificing tenacity.[S20][S35][S36]
Conventional commercial dissolving pulp is manufactured from hardwood and softwood chips using pre-hydrolysis kraft (PHK) or acid sulphite (AS) pulping.[S36][S0602] Because raw wood contains only 40 to 50 percent cellulose embedded in 20 to 30 percent lignin and 20 to 35 percent hemicelluloses, wood-pulp mills run energy-intensive digesters and bleaching towers merely to strip away half of the harvested tree mass.[S34][S36][S0602] Even after refining, reference acid sulphite dissolving wood pulp exhibits an alpha-cellulose purity of roughly 92.3 percent alongside residual pentosans.[S36]
By contrast, mature cotton lint, spinning waste, and unbleached pre-consumer cutting clips consist of 90 to over 99 percent alpha-cellulose.[S34][S36][S0602] Laboratory characterisation of three pre-consumer 100 percent cotton fabrics (Cot 1, Cot 7, and Cot 33) at Durban University of Technology confirmed untreated alpha-cellulose contents of 99.4 percent, 99.0 percent, and 99.1 percent respectively, beating the 92.3 percent wood dissolving pulp baseline by nearly 7 percentage points.[S36] Untreated cotton fabrics also showed 18 percent sodium hydroxide alkali solubility (S18, measuring degraded hemicellulose and gamma-cellulose) of only 0.28 to 1.14 percent and 10 percent alkali solubility (S10) of 0.80 to 1.24 percent, compared with 4.94 percent S18 and 10.50 percent S10 in reference wood pulp.[S36]
Substituting cotton textile waste and linters for wood dissolving pulp starts with a lignin-free feedstock rich in alpha-cellulose.[S34][S36] European Commission analyses establish that textiles rank fourth highest among European Union consumption categories for overall environmental and climate impact and third highest for water and land use.[S38] Diverting pre-consumer cotton clips and linters into dissolving pulp displaces forestry land use and reduces textile carbon dioxide emissions by up to 33 percent when circular recycling replaces virgin extraction.[S36][S38]
6.4
Alpha-cellulose purity
Alpha-cellulose purity: 98.8 percent · sourced
If cotton waste has higher alpha-cellulose purity than wood pulp, why cannot a spinner feed shredded cotton clips directly into a viscose or Lyocell dissolver?
Pulp mass yield
Pulp mass yield: 88 percent · sourced
Pulp whiteness
Pulp whiteness: 85.8 percent · sourced
DES solvent recovery
DES solvent recovery: 80.8 percent · sourced
Fibre elongation at break
Fibre elongation at break: 13.6 percent · sourced
Experimental performance metrics from hydrated choline chloride / lactic acid / water (30% water content) depolymerisation of waste cotton textiles from DP 2,409 to DP 500-700, followed by wet-spinning into regenerated cellulose fibres (breaking strength 1.27 cN/dtex, iron content 17.01 ppm) (S34).
Unit: percent. Status: sourced. Sources: S34.
6.4 · the bodyExhibit 27 above; its figures are illustrative where marked.
If cotton waste has higher alpha-cellulose purity than wood pulp, why cannot a spinner feed shredded cotton clips directly into a viscose or Lyocell dissolver?[S34][S36] The primary chemical obstacle is the excessively high Degree of Polymerisation (DP) and intrinsic viscosity of native and pre-consumer cotton cellulose.[S34][S36] Degree of polymerisation measures the average number of anhydroglucose monomer units linked inside a cellulose chain; scoured and dyed pre-consumer cotton textiles retain a DP above 2,000, such as the baseline DP of 2,409 measured in recent deep eutectic solvent trials.[S34]
scoured and dyed pre-consumer cotton textiles retain a DP above 2,000
S34
Commercial viscose and Lyocell lines are engineered around wood dissolving pulps whose DP has been lowered into a window of 500 to 900 (and aged down to 250 to 350 in alkali cellulose prior to xanthation).[S34][S36] Because every anhydroglucose ring carries three hydroxyl groups that form dense intramolecular and intermolecular hydrogen bonds, a polymer chain of 2,409 glucose units exhibits severe hydrodynamic entanglement in solution.[S34][S35]
Size-exclusion chromatography (SEC) of untreated pre-consumer cotton fabrics quantifies this macromolecular gap.[S36] In the Durban University of Technology study, untreated cotton fabrics Cot 1 and Cot 7 recorded weight-average molecular masses (Mw) of 975,078 g/mol and 961,810 g/mol, and number-average molecular masses (Mn) of 448,006 g/mol and 566,816 g/mol.[S36] Commercial acid sulphite wood pulp (AS DWP) recorded an Mw of 204,865 g/mol and Mn of 113,041 g/mol, while pre-hydrolysis kraft (PHK) wood pulp recorded an Mw of 412,185 g/mol and Mn of 219,498 g/mol.[S36]
With four times the molecular mass of acid sulphite wood pulp, untreated cotton fabrics exhibited cupriethylenediamine intrinsic viscosities between 1,313 and 1,415 mL/g (1,415 mL/g for Cot 1, 1,313 mL/g for Cot 7, and 1,397 mL/g for Cot 33), far above the 400 to 600 mL/g viscose window (502 mL/g for AS DWP).[S36] Attempting to dissolve DP 2,409 cotton waste directly produces an unpumpable gel that blinds candle filters, raises the Treiber filter-clogging value (Kw), and ruptures filaments at the spinneret.[S34][S36]
Overcoming the viscosity barrier requires controlled cleavage of glycosidic bonds without over-hydrolysing chains into sugars or collapsing pores through hornification.[S34][S35][S36] Peer-reviewed research published in 2026 demonstrated a solvent-mediated strategy using a hydrated deep eutectic solvent (DES) of choline chloride, lactic acid, and water to convert waste cotton textiles into dissolving pulp.[S34] By tuning the water content to 30 percent, researchers controllably reduced the DP of waste cotton pulp from 2,409 into the target 500 to 700 window while preserving chemical composition and cellulose I crystallinity.[S34] The process sequence from high-DP cotton waste to wet-spun filament is mapped in Exhibit 26.[S34][S35][S36]
As shown in Exhibit 26, controlling the depolymerisation window between DP 500 and 700 bridges the gap between raw textile waste and filament extrusion, though process-flow diagrams cannot establish continuous reactor heat-transfer performance.[S34][S35] Quantitative pulp and fibre metrics from the hydrated DES route are presented in Exhibit 27.[S34]
…the depolymerisation window between DP 500 and 700 bridges the gap between raw textile…
S34, S35
The benchmarks in Exhibit 27 confirm five engineering realities for waste-cotton pulping: 98.80 percent alpha-cellulose purity, 88.01 percent gravimetric pulp yield (nearly double wood-chip pulping), 85.80 percent whiteness with 17.01 ppm iron content, 80.80 percent DES recovery, and wet-spun fibre tenacity of 1.27 cN/dtex at 13.63 percent elongation.[S34] While these laboratory results validate the macromolecular mechanism, an 80.80 percent DES recovery rate remains below the 99-plus percent recovery of industrial NMMO Lyocell plants.[S34][S35]
6.7
Exhibit 285 paragraphs step it
Read-out
| Intrinsic viscosity (mL/g) | 502 | 1,415 | 419 | 393 | 442 |
|---|---|---|---|---|---|
| Alpha-cellulose (%) | 92.3 | 99.4 | 98.5 | 97.9 | 96.7 |
| ISO brightness (%) | 92.7 | 35.7 | 32.8 | 79.2 | 97.8 |
| Alkali solubility S18 (%) | 4.9 | 0.3 | 0.9 | 1.2 | 1.8 |
| Number-average Mn (g/mol) | 113,041 | 448,006 | 111,574 | 98,290 | 102,622 |
| Weight-average Mw (g/mol) | 204,865 | 975,078 | 222,112 | 250,971 | 296,521 |
| Polydispersity (Mw/Mn) | 2.8 | 2.2 | 2.1 | 2.6 | 2.9 |
| Calcium Ca (mg/kg dry) | 19 | 406 | 36 | 238 | 22 |
| Magnesium Mg (mg/kg dry) | 4 | 135 | 6 | 74 | 8 |
Experimental data from Shangase, Chetty and Wessels (2024), Chemical Engineering Transactions Vol. 113, Tables 1, 2 and 3 (S36). AS DWP = Acid Sulphite Dissolving Wood Pulp reference; UT = Untreated pre-consumer 100% cotton fabric; TA = Treatment A (5% H2SO4 at 60 C for 50-53 min); TB = Treatment B (hypochlorite bleaching at 60 C for 30 min).
Unit: laboratory characterisation (TAPPI / ISO / SEC). Status: sourced. Sources: S36.
Existing commercial dissolving-pulp and viscose mills rely on aqueous acid hydrolysis, alkaline extraction, and oxidative bleaching to prepare cotton waste for regeneration.[S35][S36] Before dyed or finished cotton textiles enter a viscose reactor, covalent reactive dyes, vat pigments, optical brighteners, and crosslinking resins must be cleaved so they do not form insoluble gel particles during xanthation.[S35][S36]
In the 2024 Chemical Engineering Transactions study by Shangase, Chetty, and Wessels, researchers cut FTIR-verified 100 percent pre-consumer cotton waste into 2 to 3 square centimetre pieces, milled them through a 2-millimetre sieve, and evaluated two pre-treatments against Acid Sulphite Dissolving Wood Pulp (AS DWP).[S36] Treatment A applied sulphuric acid hydrolysis (5 percent H2SO4 at 60 degrees Celsius across 10 to 120 minutes), reaching ideal post-pretreatment viscosity in 53 minutes for Cot 1 (419 mL/g) and 50 minutes for Cot 7 (442 mL/g).[S36] Treatment B applied hypochlorite bleaching at 60 degrees Celsius for 30 minutes, reaching 393 mL/g for Cot 1 and 389 mL/g for Cot 7.[S36] The analytical results across TAPPI viscosity, alkali solubility, ISO brightness, SEC molecular mass, and heavy-metal ash are compiled in Exhibit 28.[S36]
Inspecting Exhibit 28 shows why pre-treatment must match the optical and mineral profile of incoming cotton waste.[S36] On dyed Cot 1 (35.7 percent brightness), acid hydrolysis (Treatment A) cut viscosity to 419 mL/g and calcium from 406 mg/kg to 36 mg/kg, but left dye chromophores intact at 32.8 percent brightness, whereas hypochlorite bleaching (Treatment B) cleaved the dye and raised brightness by 43.5 percentage points to 79.2 percent (and by 27.4 percentage points on dark Cot 33).[S36] On white Cot 7 (111.9 percent initial brightness due to optical brighteners), acid hydrolysis stripped brighteners to 97.8 percent brightness, reduced Mw from 961,810 g/mol to 296,521 g/mol, and stripped calcium from 478 mg/kg to 22 mg/kg and magnesium from 235 mg/kg to 8 mg/kg, matching reference wood pulp (19 mg/kg Ca and 4 mg/kg Mg) while retaining 96.7 percent alpha-cellulose.[S36] After alkali ageing into viscose dope, the treated cotton achieved final DPs between 267 and 324, inside the 250 to 350 viscose spinning window, though continuous filament tenacity was not measured.[S36]
Aggressive hypochlorite bleaching on dyed fabrics raised the TAPPI T 430 cm:2009 copper number (oxidative damage) from 0.21 to 9.70 on Cot 7 and from 0.162 to 4.95 on Cot 33 (over-depolymerising Cot 33 to 145 mL/g), whereas mild acid hydrolysis kept copper numbers at 1.00 to 2.10, matching the 1.27 wood-pulp reference.[S36] In Cameroon, four cellulosic streams arise in an unbleached or white state prior to dyeing: SODECOTON cottonseed linters (9,000 to 15,000 tonnes a year across a 340,000 tonne crop), spinning card strips and comber noils at Camtext SA or CICAM scale (960 to 2,160 tonnes a year on 12,000 tonnes of lint), greige selvedges, and unbleached CMT cutting clips.[R01][R03][R10][S37] Segregating unbleached clips at the cutting table allows pulp off-takers to use mild acid or hydrated DES viscosity tuning alone, preserving >98 percent alpha-cellulose and ~88 percent pulp yield.[S34][S36]
Interlude · the cloth half-woven
Woven: sections 6.0 to 6.7Still to weave: 6.10 to 6.20
Read-out
Annual fibre production is a supply measure. Landfill or burning and clothing-to-clothing recycling are end-of-life measures. The value-loss estimate also includes clothing underutilisation. No tonnage conversion or common denominator is inferred.
Unit: reported global measures, with source dates retained. Status: sourced. Sources: S02, S08, S09.
Read this exhibit in its chapter ↗6.10
Once waste cotton is depolymerised into dissolving pulp, its environmental footprint and capital threshold depend on the spinning chemistry: derivatising routes (viscose xanthate and cellulose carbamate) versus direct dissolution routes (NMMO Lyocell, ionic liquids, and deep eutectic solvents).[S34][S35][S36]
In conventional viscose production, dissolving pulp is steeped in 17 to 19 percent aqueous sodium hydroxide (NaOH), aged to DP 250 to 350, reacted with liquid carbon disulphide (CS2) into sodium cellulose xanthate, and extruded into an acidic bath containing sulphuric acid, sodium sulphate, and zinc sulphate.[S35][S36] While viscose has a massive global installed base for co-processing recycled pulps, carbon disulphide is a volatile neurotoxin and zinc sulphate requires strict effluent precipitation.[S35] Modern viscose plants require multi-stage gas-scrubbing units to recover 95 to 98 percent of sulphur emissions under Zero Discharge of Hazardous Chemicals (ZDHC) rules, making small greenfield viscose reactors inside emerging garment parks unsound.[S28][S35]
To avoid carbon disulphide, the Lyocell process dissolves cellulose directly in aqueous N-Methylmorpholine N-oxide (NMMO) at 90 to 120 degrees Celsius (around 13.3 percent water) and extrudes the dope across an air gap into an aqueous coagulation bath.[S35][S0602] VTT's July 2026 review identifies NMMO dissolution as the closest direct-solvent route to widespread industrial implementation because it builds on commercial Lyocell lines (such as REFIBRA, NuCycl, and SaXcell), achieves up to 95 percent cellulose recovery, and recycles over 99 percent of the NMMO solvent.[S35]
Alongside NMMO, three next-generation platforms are advancing: (1) Ionic liquids (Ioncell, DBNH-OAc, AmimCl, BmimCl) dissolve cotton at 80 to 130 degrees Celsius for dry-jet wet spinning while keeping polyester purity at 92 to 96 percent, though solvent cost and recycling energy remain hurdles; (2) Cellulose carbamate (CCA) reacts activated pulp with urea at 120 to 180 degrees Celsius so the carbamate dissolves in cold aqueous sodium zincate (ZnO/NaOH) and spins on standard viscose machines without CS2; and (3) Hydrated zinc chloride and deep eutectic solvents depolymerise and dissolve cotton at 60 to 100 degrees Celsius once solvent recovery rises from 80.80 percent toward 98 percent.[S34][S35][S36] These routes are compared against mechanical tearing across six engineering axes in Exhibit 29.[S20][S34][S35][S36]
Derived multi-criteria engineering comparison scored from 1 (lowest/poorest performance) to 5 (highest/best performance) across six operational dimensions: Capex efficiency (5 = lowest capital threshold), Energy efficiency (5 = lowest kWh/t), Solvent safety (5 = no toxic solvents), Staple restoration (5 = virgin-equivalent filament/staple), Short-fibre acceptance (5 = accepts <10 mm linters/dust), and Industrial readiness (5 = TRL 9 mature commercial scale) based on S20, S34, S35 and S36.
Read-out
Derived multi-criteria engineering comparison scored from 1 (lowest/poorest performance) to 5 (highest/best performance) across six operational dimensions: Capex efficiency (5 = lowest capital threshold), Energy efficiency (5 = lowest kWh/t), Solvent safety (5 = no toxic solvents), Staple restoration (5 = virgin-equivalent filament/staple), Short-fibre acceptance (5 = accepts <10 mm linters/dust), and Industrial readiness (5 = TRL 9 mature commercial scale) based on S20, S34, S35 and S36.
Unit: normalised engineering score (1 = worst, 5 = best). Status: derived. Sources: S20, S34, S35, S36.
As Exhibit 29 shows (noting that radar polygon area depends on axis ordering and is not a physical total), mechanical tearing scores 5 on capex, energy, solvent safety, and readiness (TRL 9), but 2 on staple restoration and 1 on short-fibre acceptance (<10 to 12 mm).[S20][S24] Lyocell NMMO and viscose co-processing score 4 to 5 on staple restoration and short-fibre acceptance, but require heavy chemical plants or CS2 abatement, while hydrated DES pulping remains at pilot readiness (score 2).[S34][S35][S36]
6.13
Sweden's Renewcell, founded in 2012 to convert cotton-rich waste into Circulose dissolving pulp, operated a demonstration plant in 2019, listed on Nasdaq First North in November 2020, and invested about US$140 million to launch commercial production at a former paper mill in Ortviken in December 2022.[S0601] Despite proven chemistry, Renewcell filed for bankruptcy in February 2024 before Altor Equity Partners acquired its assets three months later.[S0601] A July 2024 analysis by Renewcell's former Chief Commercial Officer identifies four structural lessons: (1) projecting a 12-month breakeven against a 12-to-18-month apparel development cycle; (2) pricing Circulose above cyclical virgin wood-pulp troughs without binding mandates; (3) shipping waste from as far as Bangladesh to Sweden and shipping pulp back to Asian spinners; and (4) relying on non-binding brand pledges that stalled under margin pressure.[S10][S0601] As Reverse Resources notes, scaling chemical recycling from 12,000 tonnes toward 200,000 tonnes a year requires clean, pre-sorted pre-consumer waste close to spinning hubs.[S10]
The antidote to the US$140 million standalone greenfield mill trap is co-processing: depolymerising cotton waste in a modular pre-treatment unit and blending it at 10:90 (10 percent) or 20:80 (20 percent) with conventional wood dissolving pulp inside an existing viscose or Lyocell plant.[S36][S0601] In the Durban University of Technology trials, Treiber filterability tests (measuring filtration value Fw, filter-clogging value Kw, and 24 to 78 second falling-ball viscosity times) proved that raising the treated cotton share to 20 percent (the 20:80 blend) improved dope homogeneity, stability, and filterability (lower Kw) through stronger intermolecular cellulose connections.[S36] A 20:80 blend also meets the 20 percent minimum certified recycled content threshold for Global Recycled Standard (GRS v4) labelling under algorithmic mass balance.[S28][S36]
6.16
Three contaminant classes must remain below strict parts-per-million (ppm, or mg/kg) tolerances: (1) Transition metals (Fe, Cu, Mn, Cr, Ni) catalyse N-O bond cleavage and rapid exothermic runaway in hot NMMO, requiring iron below 15 to 20 ppm (achieved at 17.01 ppm Fe in S34, alongside 0.28 to 7.07 mg/kg Cu and 0.21 to 0.57 mg/kg acid-treated Cr in S36); (2) Alkaline earth metals (Ca, Mg) from hard water and floor dust measured 406 to 514 mg/kg Ca and 90 to 235 mg/kg Mg in untreated cotton (S36), blinding spinneret filters until dilute sulphuric acid hydrolysis stripped them to 22 to 36 mg/kg Ca and 6 to 8 mg/kg Mg (matching the 19 mg/kg Ca and 4 mg/kg Mg wood-pulp reference); and (3) Synthetic polymers (elastane, polyester) form deformable micro-gels or oligomers that plug spinneret orifices.[S26][S34][S35][S36]
Unlike post-consumer municipal rags, pre-consumer 100 percent cotton clips segregated on GFT's cutting tables (never touching concrete floors) combined with SODECOTON linters and Camtext SA comber noils start with near-zero synthetic or metal contamination.[R03][R10][S10] Pairing table sorting with regional benchtop NIR verification (91.7 percent composition and 92.6 percent elastane accuracy across 900 to 1,700 nm, S26, as benchmarked in European sorting trials, S17) enables a Cameroon cluster to issue an analytical batch certificate with every export lot documenting polymer purity, intrinsic viscosity, and ash content.[S17][S26][S28][S36]
GFT applies a four-step calculation boundary across ginning, spinning, and cutting-room streams:[R01][S34][S36]
S34).[S34][S36]S34) to $0.9950$ (S35) cuts makeup mass by a factor of 38.[S34][S35]6.20
Unbleached CMT knit clips
Unbleached CMT knit clips: Staple length index (0 = 24 mm) 8.2, Cellulose purity index (0 = mixed, 10 = pure) 9.5. Quadrant: Mechanical rotor spinning · derived
Containing Phase 1 capital to high-utilisation CMT operations while partnering upstream and downstream avoids premature chemical reactor capex.
Colour-sorted CMT woven clips
Colour-sorted CMT woven clips: Staple length index (0 = 24 mm) 6.8, Cellulose purity index (0 = mixed, 10 = pure) 8.4. Quadrant: Mechanical rotor spinning · derived
Spinning comber noils
Spinning comber noils: Staple length index (0 = 24 mm) 3.5, Cellulose purity index (0 = mixed, 10 = pure) 9.6. Quadrant: Chemical dissolving pulp · derived
SODECOTON cotton linters
SODECOTON cotton linters: Staple length index (0 = 24 mm) 1.8, Cellulose purity index (0 = mixed, 10 = pure) 9.2. Quadrant: Chemical dissolving pulp · derived
Mechanical tearing droppings
Mechanical tearing droppings: Staple length index (0 = 24 mm) 2.4, Cellulose purity index (0 = mixed, 10 = pure) 8. Quadrant: Chemical dissolving pulp · derived
Polycotton uniform trims
Polycotton uniform trims: Staple length index (0 = 24 mm) 6.2, Cellulose purity index (0 = mixed, 10 = pure) 3.5. Quadrant: Non-woven insulation · derived
Post-consumer friperie discards
Post-consumer friperie discards: Staple length index (0 = 24 mm) 2.5, Cellulose purity index (0 = mixed, 10 = pure) 1.8. Quadrant: Fractionation or biomass · derived
The method behind it: Worked example.
Derived engineering allocation matrix plotting seven Cameroon textile and ginning waste fractions by recoverable staple length index (x-axis: 0 = 24 mm long staple) and alpha-cellulose / mono-material purity index (y-axis: 0 = mixed post-consumer synthetics, 5 = dyed/blended industrial scrap, 10 = >98% unbleached pure cotton) based on S24, S34, S35, S36 and S37.
Unit: fibre length and cellulose purity index (0 to 10). Status: derived. Sources: S24, S34, S35, S37.
6.20 · the bodyExhibit 30 above; its figures are illustrative where marked.
Containing Phase 1 capital to high-utilisation CMT operations while partnering upstream and downstream avoids premature chemical reactor capex.[R08][R09][R12][S0601]
Containing Phase 1 capital to high-utilisation CMT operations while partnering upstream and downstream avoids…
R08, R09, R12, S0601
Long, clean CMT cutting clips (18 to 24 mm after opening) belong in regional open-end rotor spinning blended at 20 to 35 percent with virgin SODECOTON lint (Chapter 5).[R03][S24][S25] Conversely, three Cameroon streams are physically too short (<12 mm) for mechanical apparel spinning and should be aggregated for chemical dissolving pulp: (1) SODECOTON cottonseed linters and gin motes (estimated at 9,000 to 15,000 tonnes a year across nine gins from a 314,455 to 350,000+ tonne seed-cotton crop); (2) Spinning comber noils and filter dust at Camtext SA's 12,000 tonne a year hub (US$300 million / 180 billion XAF) and SODECOTON-CICAM (estimated at 600 to 1,200 tonnes a year of <12 mm virgin fibers); and (3) Mechanical tearing droppings (<10 mm, 10 to 15 percent of torn clip mass) plus high-twist woven clips.[R01][R02][R03][R08][R09][R10][S20][S24][S37] This allocation is mapped in Exhibit 30.[S24][S34][S35][S37]
As Exhibit 30 demonstrates, the upper-right quadrant (Mechanical rotor spinning) captures long CMT knit and woven clips, while the upper-left quadrant (Chemical dissolving pulp) captures short, high-purity SODECOTON linters, comber noils, and tearing droppings.[S24][S34][S36][S37] Polycotton uniform trims route to Non-woven insulation (lower-right), while post-consumer friperie discards sit in the lower-left quadrant where chemical fractionation is uneconomic.[S24][S29][S35]
Consistent with GFT's four-phase programme spine (Feasibility Study Section 12) and Renewcell's lessons, committing capital to a domestic pre-treatment and dissolving-pulp module in Phase 3 (post-2030) requires four conditions precedent: (1) Aggregated domestic feedstock above 15,000 tonnes a year verified in PMS and ISO 59020 logs across SODECOTON, Camtext SA, and CMT plants operating above 75 percent utilisation; (2) Binding multi-year take-or-pay offtake contracts with MMCF spinners indexed to wood dissolving pulp plus a GRS v4 premium; (3) Demonstrated >98 percent solvent recovery (for DES/ionic liquids) or industrial hub effluent integration (for dilute acid/alkaline hydrolysis at Dibamba or Garoua); and (4) Zero elastane and polyester carryover enforced by NIR spectroscopy (Chapter 4) and mono-material design (Chapter 7).[R07][R08][R10][S26][S28][S34][S35][S36][S40][S0601]
By respecting polymer physics and industrial scale thresholds, GFT's circularity blueprint captures the macromolecular value of Cameroon's cotton harvest without exposing the greenfield garment venture to premature chemical-plant capital risk.[R06][S34][S0601] Where Chapter 6 has established how pure cotton cellulose is depolymerised and regenerated when fibres become too short for mechanical spinning, Chapter 7 confronts the chemical and design challenge that arises when cotton is blended with synthetic polyester and elastane.[S35]
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R01 · Grade C · inherited record
Inherited evidence R01
Cameroon seed-cotton production 2022-2024: 330,000 t (2022), 314,455 t (2023), about 340,000 t (2024).
Publication date unrecorded. Inherited source-text record. The original publication has not been independently reopened for this web edition.
R02 · Grade C · inherited record
Inherited evidence R02
2025 seed-cotton projection above 350,000 t.
Publication date unrecorded. Inherited source-text record. The original publication has not been independently reopened for this web edition.
R03 · Grade C · inherited record
Inherited evidence R03
Company profile: more than 220,000 cotton producers supported in northern Cameroon; nine ginning plants; two oil mills.
Publication date unrecorded. Inherited source-text record. The original publication has not been independently reopened for this web edition.
R06 · Grade C · inherited record
Inherited evidence R06
About 95 percent of cotton fibre exported raw against 5 percent processed locally; industrialisation target of 50 percent local processing.
Publication date unrecorded. Inherited source-text record. The original publication has not been independently reopened for this web edition.
R07 · Grade C · inherited record
Inherited evidence R07
SND30 restates the 50 percent local-processing target by 2030.
Publication date unrecorded. Inherited source-text record. The original publication has not been independently reopened for this web edition.
R08 · Grade C · inherited record
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Announced SODECOTON and CICAM merger to create a cotton-textile industrial pole targeted by 2030.
Publication date unrecorded. Inherited source-text record. The original publication has not been independently reopened for this web edition.
R09 · Grade C · inherited record
Inherited evidence R09
Camtext SA integrated cotton-to-textile project, US$300 million (180 billion XAF); Panafritex and Arise with SODECOTON, CNPS and Marlo; 12 November 2025.
Publication date unrecorded. Inherited source-text record. The original publication has not been independently reopened for this web edition.
R10 · Grade C · inherited record
Inherited evidence R10
Camtext SA: 12,000 t a year processed; about 12,000 jobs at the Dibamba hub and 3,000 at Garoua; return on investment near 11 years; optimal capacity around 2033.
Publication date unrecorded. Inherited source-text record. The original publication has not been independently reopened for this web edition.
R12 · Grade C · inherited record
Inherited evidence R12
CICAM capacity utilisation, July 2023 report: Garoua 33.7 percent, CICAM 1 48.9 percent, CICAM 2 10.83 percent; underutilisation cost about CFAF 2 billion in 2020.
Publication date unrecorded. Inherited source-text record. The original publication has not been independently reopened for this web edition.
R32 · Grade C · inherited record
Inherited evidence R32
CFA franc to US dollar reference rates; franc pegged to the euro at 655.957. The GFT study's method note places the franc near 590 to 610 per US dollar across the 2023 study window and near 563 to 577 more recently, and treats currency conversions as estimates.
Publication date unrecorded. Inherited source-text record. The original publication has not been independently reopened for this web edition.
c06-S10 · Grade B
In Conversation with Reverse Resource: Tackling the industry's textile waste
Reverse Resources solves a major bottleneck in textile-to-textile recycling: the lack of clean, traceable, and scalable waste supply chains. As recycling technologies scale from handling 12,000 tonnes to over 200,000 tonnes per year, the need for reliable feedstock grows dramatically.
2024-06. Register access date: 2026-10-30. Source provenance is supplied by the paper evidence register.
Open the recorded source ↗c06-S17 · Grade A
Unlocking the hidden value of cotton by-products in African least developed countries
Diversification into cotton by-products can generate sustainable parallel activities for income generation and employment in Africa.
2019-07-17. Register access date: 2026-10-30. Source provenance is supplied by the paper evidence register.
Open the recorded source ↗c06-S20 · Grade A
Study on the technical, regulatory, economic and environmental effectiveness of textile fibres recycling
The findings of this study can be used as evidence base to improve the knowledge of the effectiveness of recycling capabilities of textile waste.
2021-11. Register access date: 2026-10-30. Source provenance is supplied by the paper evidence register.
Open the recorded source ↗c06-S24 · Grade A
Circular textile value chains: Advancing local manufacturing of yarns and fabrics with recycled content in Morocco
A waste mapping study from 2021, conducted by the United Nations Industrial Development Organization (UNIDO), revealed that Morocco's textile industry produces over 83,000 tons of textile waste each year. Of this amount, 42% comprises blends containing high amounts of cotton, and 14% comprises 100% cotton fibers, both of which are considered high value.
2023-11. Register access date: 2026-10-30. Source provenance is supplied by the paper evidence register.
Open the recorded source ↗c06-S25 · Grade B
Assessing Circular Economy Potentials in North African Textile Industries
Studies found that the textile and apparel (T&A) industries in these three countries generate an estimated 326 ktons of post-industrial textile waste annually: 212 KTons from Egypt ( Switchmed, 2022 ), 83,2 KTons from Morocco and 31,1 Ktons from Tunisia ( Switchmed, 2021 ).
2022. Register access date: 2026-10-30. Source provenance is supplied by the paper evidence register.
Open the recorded source ↗c06-S26 · Grade B
Machine Learning-Based Identification of Textile Composition from NIR Spectroscopy for Automated Sorting
The best composition classification model, based on Weighted KNN, achieved an accuracy of 91.7%, showing that common mono-materials and blends can be distinguished reliably. The elastane detection model achieved an overall accuracy of 92.6%, with class-specific accuracies of 83.3% for elastanepresent samples and 95.2% for elastane-absent samples.
2026-04-22. Register access date: 2026-10-30. Source provenance is supplied by the paper evidence register.
Open the recorded source ↗c06-S28 · Grade C
GRS/RCS chain of custody + Tier 2-3 mass balance in textile PLM
The Global Recycled Standard (GRS v4) and the Recycled Claim Standard (RCS v4) require a Scope Certificate per production facility, a Transaction Certificate for each change of ownership of the material and an algorithmic mass balance when the Tier 3 chemical reactor simultaneously introduces virgin and recycled raw material.
2026-07-27. Register access date: 2026-10-30. Source provenance is supplied by the paper evidence register.
Open the recorded source ↗c06-S29 · Grade B
Addressing Fashion and Textile Waste Through Sustainable Water and Waste Management
Globally, over 92 million tons of textile waste are generated annually, with only 12% being recycled. In Kenya, the influx of second-hand clothing, commonly known as "mitumba," contributes to significant textile waste, much of which ends up in landfills and waterways.
2025-03-30. Register access date: 2026-10-30. Source provenance is supplied by the paper evidence register.
Open the recorded source ↗c06-S34 · Grade A
Targeted depolymerization of waste cotton textiles mediated by deep eutectic solvents for regenerating cellulose fibers
By tuning the water content to 30%, the DP of waste cotton pulp was controllably reduced from 2409 to the range of 500-700, while preserving chemical composition and crystalline structure. The resulting dissolving pulp exhibits an alpha-cellulose content of 98.80%, a whiteness of 85.80%, an iron content of 17.01 ppm, and a pulp yield of 88.01%.
2026. Register access date: 2026-10-30. Source provenance is supplied by the paper evidence register.
Open the recorded source ↗c06-S35 · Grade B
Recent Advances in Recycling Polyester-Cotton Blended Textiles: Review
The review finds that chemical depolymerisation of PES and selective dissolution of cellulose currently show the strongest potential for high-quality fibre-to-fibre recycling, particularly when solvent recovery systems are integrated. However, significant barriers remain, including incomplete fraction purity, degradation of cellulose DP, limited recovery of high-quality polyester intermediates, high chemical consumption, and insufficient industrial-scale demonstrations.
2026-07-31. Register access date: 2026-10-30. Source provenance is supplied by the paper evidence register.
Open the recorded source ↗c06-S36 · Grade B
Chemical Recycling of Cotton Textile Waste and Integration into Dissolving Pulp for Viscose Production
This research investigated the chemical depolymerisation of cotton textiles, aiming to transform them into a material that closely resembles commercial dissolving pulp. The treated cotton material was then blended with conventional dissolving pulp, enabling the production of man-made cellulosic fibres (MMCFs) through the well-established viscose process.
2024-11-02. Register access date: 2026-10-30. Source provenance is supplied by the paper evidence register.
Open the recorded source ↗c06-S37 · Grade A
Promoting cotton by-products in Eastern and Southern Africa: Lessons from an UNCTAD technical assistance project
The overall objective is to build countries' capacity to evaluate and pursue new opportunities to add value to cotton by-products, derived from, for example: cotton stalks, cottonseed meal or the short-staple fibres disposed of by ginners and spinners.
2019-10. Register access date: 2026-10-30. Source provenance is supplied by the paper evidence register.
Open the recorded source ↗c06-S38 · Grade A
EU Strategy for Sustainable and Circular Textiles
EU consumption of textiles has, on average, the fourth highest impact on the environment and climate change, after food, housing and mobility. It is also the third highest area of consumption for water and land use, and fifth highest for the use of primary raw materials and greenhouse gas emissions.
2024. Register access date: 2026-10-30. Source provenance is supplied by the paper evidence register.
Open the recorded source ↗c06-S40 · Grade A
ISO 59020:2024 Circular economy: Measuring and assessing circularity performance
ISO 59020 sets forth requirements and guidance for organizations to measure and assess their circularity performance within defined economic systems. This document aims to standardize the process by which organizations collect and calculate data using mandatory and optional circularity indicators, ensuring consistent and verifiable results.
2024-05. Register access date: 2026-10-30. Source provenance is supplied by the paper evidence register.
Open the recorded source ↗c06-S0601 · Grade B
What Renewcell's Former CCO Learned From Bankruptcy
With headquarters in Stockholm, Renewcell was listed on the Nasdaq First North Exchange in November 2020, raising the needed capital to launch commercial-scale production at a former paper pulp mill in December 2022. Investments in the company start-up and production site totaled about $140 million.
2024-07-24. Register access date: 2026-10-30. Source provenance is supplied by the paper evidence register.
Open the recorded source ↗c06-S0602 · Grade B
Recycling of cotton textiles: Characterization, pretreatment, and purification
Recently, it has been proposed that recycling cotton may be accomplished using post-consumer cotton to produce regenerated cellulose fibers, such as viscose and lyocell. These fibers are, today, made either from wood-derived dissolving pulp or cotton linters, both of which contain almost pure cellulose.
2016. Register access date: 2026-10-30. Source provenance is supplied by the paper evidence register.
Open the recorded source ↗S34 National Library of Medicine (PubMed). 2026.
S35 VTT Technical Research Centre of Finland and MDPI Textiles. 2026-07-31.
S36 Chemical Engineering Transactions (AIDIC). 2024-11-02.
S37 UNCTAD (UN Trade and Development). 2019-10.
S0601 Stanford Social Innovation Review. 2024-07-24.
R06 Cameroon Trade Hub. Publication date unrecorded; inherited source-text check.
R10 Ecofin Agency. Publication date unrecorded; inherited source-text check.
S20 European Commission and Refashion. 2021-11.
S24 United Nations Industrial Development Organization (UNIDO). 2023-11.
S0602 Chalmers University of Technology. 2016.
S38 European Commission Directorate-General for Environment. 2024.
R01 Business in Cameroon. Publication date unrecorded; inherited source-text check.
R03 SODECOTON. Publication date unrecorded; inherited source-text check.
S10 Fashion for Good and Reverse Resources. 2024-06.
S28 TraceWeave. 2026-07-27.
S26 University of Groningen. 2026-04-22.
S17 UNCTAD (UN Trade and Development). 2019-07-17.
R08 Business in Cameroon. Publication date unrecorded; inherited source-text check.
R09 Ecofin Agency. Publication date unrecorded; inherited source-text check.
R12 Business in Cameroon. Publication date unrecorded; inherited source-text check.
S25 Closed Loop Fashion and UNIDO SwitchMed. 2022.
R02 Fibre2Fashion; Business in Cameroon. Publication date unrecorded; inherited source-text check.
S29 Pan African Climate Justice Alliance (PACJA). 2025-03-30.
R32 Wise; XE. Publication date unrecorded; inherited source-text check.
R07 Ecofin Agency. Publication date unrecorded; inherited source-text check.
S40 International Organization for Standardization (ISO). 2024-05.
Keep the thread · chapter 06 of 14
Move the shuttle along the rack to preview any chapter: its sections, exhibits and reading time. Draft web edition. This research is not investment, legal or tax advice; illustrative models are not measured factory results.
The paper's rack · 14 boltsBolt length: reading time
01The linear trap and the pre-consumer advantage
A cotton economy gains its most recoverable textile feedstock before a garment reaches a consumer. The practical starting point is an identified, weighed and segregated factory offcut, not an anonymous bale of mixed municipal clothing.
02Part I: The Linear Trap and the Pre-Consumer Advantage
Before cloth is woven, seed cotton and lint have already generated cottonseed, linters, motes, stalks and comber noils. Their value depends on measured recovery, not on the harvest total alone.
03Part I: The Linear Trap and the Pre-Consumer Advantage
Fabric is the largest garment cost and the factory's cleanest potential secondary material. The saving comes from separating marker geometry, table execution and quality failure, then weighing each stream.
04Part II: Engineering the Recycling Routes
Mixed textile waste is nearly worthless because different polymers require incompatible recycling chemistries, making cutting-table segregation and near-infrared spectral classification the gatekeepers of circular value.
05Part II: Engineering the Recycling Routes
Mechanical tearing and garnetting require a fraction of the capital, water and energy of chemical plants, but fibre shortening limits pure recycled yarn counts unless blended with long-staple virgin cotton.
06Part II: Engineering the Recycling Routes
When cotton fibres are too short for mechanical spinning, chemical recycling dissolves cellulose chains into high-purity pulp for viscose and lyocell filaments, provided degree of polymerisation and solvent recovery are tightly controlled.
07Part II: Engineering the Recycling Routes
Separating polyester-cotton and elastane blends chemically demands selective solvents, careful energy and residue control, and proven outlets, so mono-material cotton design is the first recycling investment.
08Part III: Post-Consumer Flows, Trade Asymmetries and Producer Responsibility
European used-textile exports have nearly tripled since 2000 to around 1.4 to 1.7 million tonnes a year, shipping unrecyclable fast-fashion blends to African ports without transferring Extended Producer Responsibility funds.[^S11][^S13]
09Part III: Post-Consumer Flows, Trade Asymmetries and Producer Responsibility
Separate textile collection has been mandatory since January 2025, the revised Waste Framework Directive has been in force since October 2025, and Member States must establish textile EPR schemes by April 2028. Eco-modulated fees turn garment durability, recyclability and evidence into direct financial variables.[^S04][^S12][^S0901]
10Part III: Post-Consumer Flows, Trade Asymmetries and Producer Responsibility
Regulation (EU) 2024/1781 bans the destruction of unsold apparel and mandates public disclosure of discarded stock, making machine-learning demand forecasting and computer-vision quality control the primary defences against overproduction waste.[^S03][^R27][^R29]
11Part III: Post-Consumer Flows, Trade Asymmetries and Producer Responsibility
A recycled-content claim is only as strong as the material identity, custody documents, process-loss arithmetic and claim approval behind it. Certificates support that evidence; they do not replace it.
12Operationalising the circular factory
Weigh material where it changes hands, preserve its identity, and make each unresolved difference a management decision. Circularity then becomes an operating discipline with inspectable limits.
13Part IV: Operationalising the Circular Factory
By partnering a lean cut-make-trim garment factory with Cameroon's emerging integrated spinning poles at Dibamba and Garoua, pre-consumer cotton clips cycle back into local yarn without greenfield spinning capex.
14Part IV: Operationalising the Circular Factory
Rather than betting greenfield capital on unproven chemical reactors, a disciplined four-phase illustrative roadmap embeds cutting-table sorting and mass-balance measurement in Phase 1, scales regional mechanical blending in Phase 2, and gates advanced regeneration to Phase 3.[^S28]