Biological Retting Research Articles

An effect of retting process and extraction methods on physical and mechanical properties of areca nut fibers

PurposeThe purpose of the project is to explore the biosoftening of raw areca nut fibers using two different biological retting methods and assess their impact on fiber properties for improved spinning. The study aims to contribute to the fashion industry’s shift toward sustainability.Design/methodology/approachThe project involves collecting raw brown areca shells, subjecting them to two retting methods (stagnant water retting and changing water daily retting) and then extracting and drying the fibers. Various physical and chemical properties of the fibers are measured to evaluate their suitability for spinning.FindingsThe stagnant water retting method, especially the fibers obtained on the second day, showed improved properties in terms of fiber strength, elongation, fineness and cellulose content, making them suitable for spinning applications. The method also resulted in better moisture regain.Research limitations/implicationsThe study focused on two retting methods and a limited timeframe. Further research could explore additional techniques and durations. The labor-intensive nature of the daily changing water retting method may have implications for scalability.Practical implicationsThe project demonstrates a cost-effective and sustainable method for converting agricultural waste (areca nut husks) into valuable fibers suitable for various end users.Social implicationsThe research supports the fashion industry’s sustainability efforts by promoting the use of eco-friendly natural fibers, potentially benefiting rural farming communities.Originality/valueThe project highlights the innovative use of areca nut fibers and their potential to contribute to sustainable fashion. The stagnant water retting method is presented as a reliable and effective approach for improving fiber properties. Additionally, all fiber testing was exclusively conducted at the South India Textile Research Association (SITRA), with sponsorship from the industry and support from the Ministry of Textiles, Government of India.

Influence of the Sampling Area on the Chemical, Physical, and Mechanical Properties of Grewia bicolor(GB) Fiber for Potential Use in the Reinforcement of Tannin Matrix Composites

ABSTRACT The aim of this study is to chemically, physically, and mechanically characterize Grewia bicolor (GB) fibers harvested in the NGONG locality located in the North Cameroon region for potential use in the elaboration of tannin matrix composites. The fibers are extracted from three zones of the stem (top (T), middle (M), and bottom (B)) by biological retting with stagnant water, and the various standard norms are respected for different tests. Analysis by Fourier transform infrared spectroscopy (FTIR) and chemical composition show that GB fibers consist mainly of cellulose (50.73–53.67%), hemicellulose (20.95–24.73%), and lignin (14.26–17.26%). Physical properties give: true density (1.33–1.35 g/cm3), bulk density (0.61–0.72 g/cm3), porosity (48.37–51.4%), linear density (17.28–29.44 tex), water content (13.16–13.59%), water absorption rate (121.86–134.54%), and a moisture recovery rate at 75% relative humidity (11.12–11.76%). Mechanical parameters give Young’s modulus (17.21–29.56 GPa), stress at break (504.71–936.09 MPa), and strain at break (4.65–5.37%). Analysis of variance (ANOVA) combined with Tukey’s test for mechanical properties show that the bottom and middle fibers are identical at the 95% confidence level. GB fibers can be used in the reinforcement of tannin matrix composites with preferable and indiscriminate sampling in the bottom and middle zones of the stem.

Investigation of chemical, physical and morpho-mechanical properties of banana-plantain stalk fibers for ropes and woven fabrics used in composite and limited-lifespan geotextile

This study aimed to assess the potential of banana-plantain stalk fibers (BPSF) as a raw material for ropes and fabrics used in composites and geotextiles. Fibers were obtained by Biological retting and ropes used for geotextile weaving were obtained by three-strand twisting in order to optimize the mechanical properties of geostalk. The thermal, physical, chemical and mechanical characteristics of the fibers were studied in order to assess the impact of the extraction process on fiber performance. In addition, the microstructure of fibers and ropes was analyzed using Scanning Electron Microscopy (SEM) and the results highlighted the presence of cellulose microfibrils parallel to fiber axis and hemicellulose linked by lignin matrix. These constituents are organized in three concentric layers around the lumen. Elementary chemical analyses using X-ray energy dispersion (EDS), Fourier Transform Infrared (FTIR) and chemical deconstruction using Jayme-Wise protocol were carried out to determine the chemical composition of BPSF, which consists of 51.5 % Carbon, 47.07 % Oxygen and mineral salts that can be highly contribute to soil fertilization after degradation. These chemical constituents represent 40 % cellulose, 21.5 % hemicellulose, 24 % lignin, 0.34 % pectin, 7.2 % lip soluble extractable and 7.36 % water-soluble sugars present in BPSF. Thermal properties of BPSF have been investigated showing the initial degradation around 200 °C. Physical analysis and uniaxial tensile testing were performed to determine the multi-scale physical and mechanical properties of geostalk. Statistical evaluation using Weibull distribution established an increasing rate of physical and mechanical properties from the finest scale to the macroscopic scale. Thus, from the BPSF to the ropes, titer increases from 42.5 ± 4.5 g/km to 7983.4 ± 132 g/km and elongation at break increases from 0.75 ± 0.29 mm for the fibers to 52.42 ± 18.91 mm for geostalk. With mass per unit area of 1869 g/m2, the tensile stress of 1281.05 ± 273 MPa and maximum strength of 15.4 ± 1.74 kN/m, geostalk is a sustainable woven fabric alternative to geosynthetics for soil reinforcement as other limited lifespan geotextiles (geojute, geocoir and geosisal). In addition, the thermal stability and high mechanical properties of fibers and ropes suggest their potential application as reinforced phases in composite materials.

Extraction, characterization and properties evaluation of pineapple leaf fibers from Azores pineapple

Pineapple leaves can provide competitive and high-quality fibers for textile purposes. Despite pineapple being cultivated in the Portugues islands there is still a technology gap for the extraction and treatment of Pineapple Leaf Fibers (PALF) in Europe. Since Azorean Pineapple differs significantly from other plants in the bromeliad family, the properties and characterization of its leaf fibers were explored for the first time. Long fibers have been extracted by hand scraping and compared to biological retting at 25 °C for different time periods. It was explored the properties of PALF from plants of different ages (11- and 18-months) and from different zones of the leaves (beginning, middle, and tip). Physical-mechanical properties of Azores PALF were determined, including diameter, linear density, strength, Young's modulus, and elongation at break and characterized by ATR-FTIR, XRD, TGA/DTG, and FESEM to understand their chemical and morphological characteristics. While slight differences were observed between different ages, variations in physical-mechanical properties were notable among fibers extracted from different leaf positions. Extraction of Azores PALF through 25 °C biological retting for 14 days effectively eliminated non-fibrous matter and produced the thinnest and strongest fibers. These fibers ranged between 34.9 and 168.3 μm in diameter, 1.39 and 7.07 tex in linear mass density, 37–993 MPa in tensile strength, 1.0–3.9 % in elongation at break, and 2.4–21.8 GPa in Young's modulus.

Mercerized Cymbopogon nardus shoot fiber as reinforcing filler

In this study, extraction of Cymbopogon nardus shoot fiber (CNSF) was performed through biological retting. Thereafter, the fibers were mercerized in a 5 % (w/v) sodium hydroxide solution. The CNSF, resulted through a 60 min mercerization process, with a higher cellulose fraction was selected as the optimally mercerized fiber. Lignin and wax were not found in the mercerized CNSF and a considerable amount of hemicellulose was also found to be removed. The temperature where the degradation rate is maximum increased from 326 °C to 344 °C, which denotes an increase in thermal stability. For practical applications as reinforcements, fibers with a rough surface were preferred. Energy-dispersive X-ray spectroscopy analyses revealed the presence of silicon on the exterior of the optimally mercerized CNSF. Moreover, the average surface roughness of the optimally mercerized CNSF increased from 20.88 to 24.22 nm, indicating an impurity-free surface. The tensile strength of the CNSF increased from 435.9 ± 16.05 to 470.8 ± 13.16 MPa, whereas the modulus increased from 55.25 ± 6.10 to 70.10 ± 7.70 GPa.

Characterization of Grewia bicolor fibre and its use in the development of composites

ABSTRACT The fibre of Grewia bicolor bark (GB) was extracted and used as reinforcement for the development fibreboards using orthophtalique unsaturated polyester (UP) as a matrix. Two methods of extraction of fibres were used, namely biological retting and chemical extraction by a sodium hydroxide solution at a 5% concentration. Chemical, Physical, mechanical, and thermal characteristics were determined using ATF FTIR, mechanical test and thermogravimetric analysis. The theoretical density of the characterized fibres was 1.30 g/cm3. The porosity decreases by 5% from the root to the leaves. The SEM analysis indicated the presence of fibrils coated with a rough sheath similar to a honeycomb cell structure. The use of NaOH in the extraction method removes the hemicellulose, pectin, wax, and lignin from the fibres. The average elasticity modulus of untreated and treated fibres are, respectively, E = 35.18 ± 2.25 MPa and E = 33.47 ± 2.35 MPa and internal bond of fibreboards are 0.98 ± 0.05 MPa and 1.06 ± 0.02 MPa.

Effect of retting methods on molecular weight of Agave atroverance fibers

This study was undertaken to investigate the effect of retting method on the molecular weight of different portion of the Agave atroverance fiber (top, middle and bottom) extracted by different retting techniques. The raw fibers from Agave atroverance plant were retted by biological and chemical (degumming) retting methods. In biological retting method both the stagnant and boil water were utilized and in chemical retting method, the extracted fibres were treated with the 5% NaOH. Agave atroverance fiber is not purely cellulosic fiber. Percentage composition of different portion of the raw fiber was also determined. It contains α-cellulose, hemicellulose, nitrogenous matter, mineral matters and miscellaneous. The retted fibres were tested for determination of molecular weight. The percentage loss of molecular weight was found to be more in case of chemically retted fibres owing to the enhanced digestibility of lignocellulosic material by 4% sodium chlorite solution. Contrary to this, biological retting showed higher molecular weight due to the presence of higher cellulosic matter and removal of pectic substabces.

Extraction and characterization of curcuma zedoaria pseudo-stems fibers for textile application

PurposeThis study aims to characterize the properties of natural cellulose fiber from the pseudo-stems of the curcuma zedoaria plant.Design/methodology/approachThe fiber was extracted using the biological retting process (cold-water retting). The intrinsic fiber properties obtained were used to evaluate the possibility of using fiber for textile applications.FindingsThe average length of a curcuma zedoaria fiber was 34.77 cm with a fineness value of 6.72 Tex. A bundle of curcuma zedoaria fibers was comprised of many elementary fibers. Curcuma zedoaria had an irregular cross-section, with the lumen having a varied oval shape. Curcuma zedoaria fibers had tenacity and elongation value of 3.32 gf/denier and 6.95%, respectively. Curcuma zedoaria fibers had a coefficient of friction value of 0.46. Curcuma zedoaria fibers belong to a hygroscopic fiber type with a moisture regain value of 10.29%.Originality/valueExtraction and Characterization of Curcuma zedoaria Pseudo-stems Fibers for Textile Application.

Comparison of Morphological and Chemical Properties of Musa Velutina Fiber Extracted through Different Extraction Method

ABSTRACT Natural fibers are being used for the last few decades as an alternative to synthetic fibers for their eco-friendly nature. But still, there is a scientific gap to address cost-effective and environmentally sustainable fiber extraction method with minimum waste production. Therefore, a study was carried out on the extraction of fiber from naturally occurring Musa velutina (wild banana plant) adopting different extraction methods. Wild banana plant fiber was extracted by chemical and biological process. Chemical extraction was carried out using Sodium hydroxide at two different concentrations (3% and 5%). The temperature was maintained at 100 ± 50°C and the bath ratio maintained at 1:7 for 2 h. Fiber yield was obtained from 20.32% to 22.56% for both concentrations. Similarly, the biological retting process was also executed using potential lignolytic bacterial (e.g. Bacillusacidicola) and fungal (e.g. Chaetomium sp.) strains. Fiber yield in the biological process was obtained at the range 21.32–31.02%. Proximate chemical analysis and SEM of extracted fiber were determined. Among the methods, the biological extraction method is found suitable in comparison to the chemical process.

Extraction and characterization of novel fibers from Vernonia elaeagnifolia as a potential textile fiber

Vernonia elaeagnifolia plant is primarily used for the wall ornamentations and is abundantly available in countries like Pakistan, India, Burma, etc. The aim of this study is to investigate the use of Vernonia elaeagnifolia as a potential source of natural fibers for the first time and to compare the performance properties with conventional textile fibers. The fibers were extracted from the Vernonia elaeagnifolia plant by biological retting process, which is a green route for the extraction of natural fibers. The material functional groups were studied by the Fourier Transform Infrared spectroscopy. The morphology of extracted fibers was investigated using scanning electron microscopy, the thermal behavior through thermogravimetric analyses and mechanical behavior was tested using single fiber tensile tester (tenacity 16.30 cN/Tex). The volume density of fibers was measured by means of microscopic analysis and its weight (found to be 1.30 g/cm3). The moisture regain of the fibers was evaluated by the oven-dry method to be 9.22%. The performance properties of these fibers are comparable with conventional fibers. They may be used as a reinforcement in polymeric composite materials as they are mechanically as well as thermally stable.

Extraction and Characterization of Natural Fibres from Plantain (Musa paradisiaca) Stalk Wastes

Plantain stalks obtained from solid waste stream of Ganmo market in Ilorin was used in this study. Natural fibres extraction from waste plantain stalk was achieved using biological retting methods. The natural fibre was rented from the waste stalk after 24 days of soaking in water. The extracted fibres were exposed to 2, 4 and 6% alkali solution (NaOH) treatment for two hours, washed and dried in the oven for 7 hours. Elemental analysis of raw plantain fibres showed the presence of elements like Indium, Potassium, Silicon and Calcium among others. Tensile strength analysis of the fibres, for single fibre strands showed that the 2% treated fibre showed distinctly promising potential with the highest tensile characteristics of young modulus, stress at break and force at peak of 52864.366N/mm2, 5398.536N/mm2 and 2.650N, respectively. Evaluation of the chemical composition of plantain by FTIR spectroscopy indicated that treatment of natural fibres using NaOH beyond 2% have a negative impact on the plantain fibre properties. Through alkali exposure, the fibre configuration presents small variations in composition. It is consequently apparent that alkali treatment with concentration of less than 2% NaOH is sufficient to remove hemicelluloses and to obtain the optimum tensile effect.

Effect of retting methods on properties ofDhaincha fibres

The dried ribbons of Sesbania aculeata (Dhaincha) plant were retted by chemical and biological retting methods. In first chemical retting method, the fibres were treated with the combination of EDTA and NaOH whereas in second method pretreated with HCl followed by NaOH; In biological retting method both the stagnant and running water methods were utilized. The retted fibres were tested for physical properties such as, moisture content and weightloss. The percentage weight loss was found to be more in case of chemically retted fibres owing to the enhanced digestibility of lignocellulosic material by the alkali. Contrary to this, biological retting showed higher moisture content due to the presence of non cellulosic matter. Overall, the properties exhibited by Sesbania aculeata fibres obtained after 15 days of stagnant water retting was comparatively good as compared to other retting methods in terms of weight loss and moisture content.

Recovery of fibers and biomethane from banana peduncles biomass through anaerobic digestion

Banana crop produces large quantities of post-harvest biomass wastes. Some of them are a potential resource of raw materials such as natural fibers, which can be used as reinforcement for composite materials. The recovery of fibers, after bioconversion of the more digestible soft tissues to biogas was assessed for peduncles of three banana varieties (Grande Naine (GN), Pelipita (PPT) and CRBP969). Fibers were sieved out from the digestate. Biogas was monitored manometrically and with gas chromatography. PPT peduncle produced both the highest fibers recovery (0.2g_DM_fiber/g_DM_initial_substrate) and methane production (260ml_CH4/g_COD_initial_substrate) after 74days of anaerobic digestion. This variety was the most suitable candidate to combine both fiber recovery and biomethane production through anaerobic digestion. GN peduncle fibers degraded in less than 20days. This variety was more convenient for biomethane production (around 210ml_CH4/g_COD_initial_substrate). The amount and the quality of recovered fibers strongly depended both on the duration of anaerobic digestion and the banana variety. This work showed that anaerobic digestion was an effective bioprocess alternative to mechanical decortication and biological retting processes for fiber extraction from banana peduncles biomass.

Characterization, modification and use of biomass: okra fibers

In the present study, fibers were extracted from different parts of okra stem and branches by way of biological retting. The extracted fibers were subjected to chemical and enzymatic treatments. The effects of the treatments on the fibers’ physical, mechanical, chemical and morphological aspects were investigated. The dyeability of the fibers with industrial green mate (Paraguayan tea) waste was studied. The heavy metal ion adsorption capability of okra bast fibers from aqueous systems was examined. The ranges for properties of the produced okra bast fibers can be summarized as linear density of 14·7–26·9 tex (g/km), initial modulus of 862–1358 cN/tex, breaking tenacity of 24–35 cN/tex, elongation of 2·5–3·2% and water absorption of 67·2–84·8%. As a mordant, iron sulfate resulted in higher color strength (K/S) for fibers dyed with the green mate tea waste compared to potassium aluminum sulfate (alum). Use of okra bast fibers resulted in iron (III), copper (II) and chromium (III) ion concentration decreases, as high as 71–98%, in aqueous solutions for pH values under 7.

New Approaches to Cellulose Microfibril Isolation from Musaceae Agro-Industrial Residues

In this work, Musaceae isolated vascular bundles from rachis agro-industrial residues were evaluated as a potential source of cellulose microfibrils. For vascular bundle isolation, a biological retting was used. For cellulose microfibril isolation, two different alkaline treatments (sodium hydroxide or potassium hydroxide combined with bleaching and acid steps) were used in conjunction with a mechanical process. Cellulose microfibrils using both alkaline processes were successfully isolated, and the presence of non-cellulosic components, especially lignin and some hemicellulose as arabinose and galactose were reduced. In spite of an important amount of oxides being removed during the biological retting, XRF analysis revealed that calcium minerals were still present in the vascular bundles, and they can affect the cellulose microfibril isolation. AFM micrographs of isolated samples revealed cellulose microfibril bundles, and their presence can be associated with non-cellulosic components still present in the samples. Thermal analysis showed that when potassium hydroxide was used, a higher reduction of lignin was observed. Nevertheless, X-ray diffractions indicated no change in the crystallization pattern of cellulose I had occurred due to the isolation process used.

Elucidation of the fibrous structure of Musaceae maturate rachis

In the last years several composites and high performance materials with woody and non-woody natural fibers have been developed. In this study, a morphological study of agricultural residues as rachis from Musaceae plants cultivated in Colombia has been carried out. Fibrous structures as fiber bundles, elementary or ultimate fibers and even cellulose microfibrils grouped together into microfibril bundles have been observed. Both biological retting and chemical procedures like alkali treatments combined with alkaline peroxide and acid addition have been used. Different microscopic techniques as optical (OM), confocal (CM), scanning electron (SEM), and atomic force (AFM) ones have been used for analysis of isolated samples. A hierarchical arrangement from conducting tissues and fiber bundles to cellulose microfibrils in Musaceae rachis has been noted. All of these structures can be isolated by biological and chemical processes at the corresponding arrangement level. This means that Musaceae rachises constitute a source of new interesting biodegradable raw materials with multiple possibilities in dimensions and morphologies for several industries. A strong presence of crystal structures exists on fiber surfaces, being their occurrence related to the maturate state of rachis samples. Additionally, a top-down scheme is proposed for understanding the structuration of rachis at each length scale.

Plantain fibre bundles isolated from Colombian agro-industrial residues

Comestible fruit production from Musaceas plants is an important economical activity in developing countries like Colombia. However, it generates a large amount of agro-industrial residues. Some of them are a potential resource of natural fibres, which can be used as reinforcement for composite materials. In this work, a series of commercial plantain ( Musa AAB, cv “Dominico Harton”) fibre bundles extracted from pseudostem, leaf sheath and rachis agricultural wastes were analyzed. Mechanical decortication and biological retting processes were used during fiber extraction. No significant differences in composition of vascular bundles were observed for both extraction processes. Gross morphological characteristics and mechanical behavior have been evaluated. Conducting tissues with spiral-like arrangement are observed attached to fibre bundles. This fact suggests a big amount of these tissues in commercial plantain plants. Both used extraction methods are not enough to remove them. Pseudostem fibre bundles have higher specific strength and modulus and lower strain at break than leaf sheath and rachis fibre bundles, having values comparable to other lignocellulosic fibres bundles.

Chemical and Biological Retting of Kenaf Fibers

The physical and chemical characteristics of fibers after biological, chemical, and enzymatic retting were studied for kenaf cultivated in Jeju, Korea. Retting removes non-fibrous materials leaving separated fibers. Quantitative chemical analyses of kenaf fibers after retting were conducted using gas chromatography—mass spectrometry (GC— MS). Before retting, the syringyl lignin content was 16 mg/g and guaiacyl lignin content was 2.9 mg/g. The syringyl content was reduced by all three retting treatments: bio-retting, chemical retting with NaOH and enzymatic retting with pectinase. Treatment with 3% pectinase decreased the syringyl lignin content to almost one-half that observed in the unretted kenaf and also decreased the guaiacyl lignin content. The ratio of syringyl type lignin/guaiacyl type lignin ranged from 5.8 down to 2.4. Thermogravimetric analysis and differential scanning calorimetry also demonstrated the reduction in non-cellulose content. Viscosity measurements show that the retting processes did not degrade the cellulose polymers of the kenaf fibers.

Byssinosis in Hemp Mill Workers

Abstract This review article concerns byssinosis, a respiratory disease that affects workers in textile mills. According to experts in the field of occupational medicine, hemp mill workers suffer worse than workers in flax, cotton, jute, and sisal mills. The causative factor in hemp dust has not been determined with certainty. However, this review assembles evidence that implicates hemp dust contaminated by bacterial endotoxins, rather than fungal toxins or constituents in hemp itself. Endotoxins are expressed by Gram negative bacteria, and Enterobacter cloacae is a prime suspect. It is proposed that endotoxin contamination occurs during the biological retting process, and not before (in living hemp plants) or after (within the textile mill). Methods of preventing and treating byssinosis are assessed, including some new proposals for management.

BYSSINOSIS PREVALENCE AND FLAX PROCESSING.

Previous evidence suggested that byssinosis in flax workers is caused by the inhalation of dust of biologically retted flax. In the present study no cases of byssinosis were found among workers in a flax plant which produces yarn by chemical degumming instead of biological retting. The absence of byssinosis in this plant could not be attributed to differences in the quantities of dust developed as compared with the conventional retting procedure. These findings support the view that the agent in flax dust which causes symptoms of byssinosis originates during biological retting of flax and is absent from unretted flax. Chemical degumming of flax appears to be superior to biological retting procedures with respect to the health of the workers.