Waste Cotton Fabrics Research Articles

Preparation of phosphorus-nitrogen synergistic flame retardant cellulose composite aerogel from waste cotton/phytic acid/acrylamide

Cellulose aerogel is a green and biodegradable material, but the high flammability of cellulose aerogel hinders its development. In order to expand the application range of cellulose aerogel, it is necessary to improve the flame retardancy of cellulose aerogel. In this paper, cellulose hydrogels were prepared by decolorizing waste cotton fabrics (WCF) and dissolving them in 1-butyl-3-methylimidazole chloride salt ([Bmim]Cl)/DMSO. The cellulose hydrogels were impregnated in aqueous phytic acid (PA)/acrylamide (AM) solution for a period of time and then heated and treated. A cellulose composite aerogel with excellent flame retardant properties was successfully prepared by using in situ polymerization. The results show that the cellulose composite aerogel has a porous structure and good thermal stability, and the residual carbon content in the air at 800 °C is >2.86 %. At the same time, it has excellent flame retardancy, the ultimate oxygen index (LOL) is >40, and the vertical combustion carbon length is <3.5 cm. The thermal insulation performance has also been improved, and the composite aerogel with a height of 1 cm has a temperature difference of 40.2 °C between the upper and lower surfaces on the 80 °C heating table.

Fabrication of Ni-foam-assisted graphene@MnO2-doped carbon fabric electrodes from waste cotton fabrics for supercapacitors

Fabrication of Ni-foam-assisted graphene@MnO2-doped carbon fabric electrodes from waste cotton fabrics for supercapacitors

Preparation and Characterization of Waste Cotton Fabric Reinforced Polylactic Acid Green Composites with Multifunctional Properties in a Low-Carbon Process

The development and design of eco-friendly materials prove crucial for promoting the recycling of waste cotton textiles and reducing environmental pollution. In this study, waste cotton fabric (WCF) and polylactic acid (PLA) serve to produce cotton fabric-reinforced PLA composite material (CF/P). The CF/P is then integrated with traditional porous sound-absorbing materials to create a novel composite plate. This research highlights the potential of WCF reinforced plates for sound absorption and thermal insulation applications in the construction field of construction and reports the effects of variables such as hot pressing temperature, WCF mass fraction, and WCF layer alignment angle on the material properties. The optimum tensile strength, water absorption, and thermal conductivity of the prepared CF/P are 64.2 ± 1.8MPa, 1.98% ± 0.04%, and 0.03W/(m·K), respectively. By combining with porous sound-absorbing materials and modifying the layering structure of composite plates, its acoustic performance can be adjusted. The highest Sound Absorption Average (SAA) of plates with a multilayer composite structure is 0.67. Direct shaping through hot pressing diminishes the use of adhesives, thereby reducing costs and health hazards. This approach offers a practical and efficient solution for the recycling and repurposing of natural fibers.

From waste to advanced resource: Techno-economic and life cycle assessment behind the integration of polyester recycling and glucose production to valorize fast fashion garments

This work demonstrates the technical, economical, and environmental viability of integrating enzymatic hydrolysis, mechanical refining, and total chlorine-free (TCF) bleaching processes for industrial-scale production of glucose from textile waste. The process features an innovative mechanical refining pretreatment coupled with TCF oxidation of dyes to achieve over 90% improvement in enzymatic hydrolysis yields of cotton textile waste while also promoting the purification and recycling of synthetic fibers. A comprehensive techno-economic analysis was performed based on a 14,000 bone dry tons (BD tons) annual glucose production line, utilizing both 100% cotton and cotton/polyester blends, reveals capital investments ranging from USD 5.6 to 7.9 million, with manufacturing costs per ton of glucose varying between USD 215 and USD 475, depending on the textile blend used. The cotton/polyester 50/50 blend scenario had the lowest minimum selling price (USD 290 per ton of glucose) due to the revenue from the unhydrolyzed synthetic fibers, which are a valuable and key co-product. A sensitivity analysis highlights the significant influence of recycled polyester content and market prices on the economics. Additionally, a life cycle assessment was performed to compare the carbon footprint of the four scenarios. In contrast to other existing pretreatments that can contribute to up to 70% of the emissions in enzymatic hydrolysis of textiles, the mechanical refining pretreatment can contribute as low as 10% of the total emissions in the process proposed in this work. While certain challenges remain, such as the development of a robust supply chain model, the conversion pathway shown in this work for upcycling cotton textile waste into value-added chemicals represents a promising opportunity to combat textile landfilling and foster the circular economy within the industry.

A greener approach for physical separation of polycotton textile waste

Most textile waste ends up in the landfill. Clearly, enhancing textile recycling is urgently needed. For circularity, efficient means for separating the constituents of the textile blends is crucial. Targeting the popular polycotton textile blend, a method was developed to physically separate cotton and PET (polyethylene terephthalate) from waste textiles. First, the waste polycotton textile was milled into smaller fibers to mitigate entanglement. Then, leveraging the relatively higher hydrophilicity of cotton, three liquids (namely, water, mineral oil, and ethanol) were mixed to form a two-phase liquid-liquid system, which induced the preferential segregation of cotton to the water-rich bottom liquid phase. Factors studied included liquid composition and milling method. The best-performing liquid mixture allowed for 84.7 % of the cotton and 85.5 % of the PET from the waste polycotton (WPC) sample to be recovered respectively from the bottom liquid phase (BLP) and top liquid phase (TLP). The separation effectiveness can be further enhanced if fiber entanglement issue can be mitigated. The recovery of about 99.9 % PET and 86.7 % cotton from a prepared mixture of pure cotton and pure PET textile wastes is a case in point, demonstrating the efficacy of the method that is fast, at ambient condition, and does not require extensive chemicals. While the interwoven design of cotton and PET in textiles confers benefits like comfort and strength, the resulting entanglement is detrimental for circularity. SynopsisAn eco-friendly yet rapid two-phase liquid-liquid system was developed for separating polycotton textile fibers, aimed at enhancing sustainability and circularity

Synthesis of Bio-Oil via Catalytic Co-Pyrolysis of Cotton Fabric Waste and Polypropylene Plastic Waste

The growing energy demand and rising environmental concerns pose severe difficulties for future generations in maintaining energy sustainability. Therefore, it is critical to explore alternative green energy sources. Hence, this study synthesized renewable bio-oil by utilizing biomass of cotton fabric waste (CFW) and polypropylene plastic waste (PPW) as feedstocks. Titanium and alumina extracted from industrial solid waste (Ti-EA) were selected as catalysts due to their active sites promoting co-pyrolysis reaction towards bio-oil formation. The Ti-EA catalyst was prepared via the wet impregnation method at different calcination times. The bio-oil was synthesized via co-pyrolysis of CFW and PPW in a fixed bed reactor at the reaction temperature of 600 °C for 1 h. The effects of the catalyst calcination time were evaluated based on the bio-oil yield and product distribution. Moreover, the catalysts were characterized by BET and FTIR. The findings show that the Ti-EA catalyst calcined at 4 h (Ti-EA-4) obtained the highest bio-oil yield of 68% whereas calcination at 6 h (Ti-EA-6) gave the lowest yield of 28%. The BET shows that the Ti-EA-4 catalyst has a higher surface area of 121.6 m2/g than the Ti-EA-6 catalyst of 96.74 m2/g. This indicates that surface area is an important characteristic that promotes efficient catalytic activity for bio-oil production. Meanwhile, FTIR results show that the catalysts have similar surface functional groups mainly O-H stretching vibrations. Overall, Ti-EA catalyst calcined at 4 h has exhibited good performance in producing bio-oil via co-pyrolysis of CFW and PPW. Thus, Ti-EA catalyst has the potential to produce bio-oil as fuel, which contributes towards waste to energy conversion and environmental preservation.

Development and Evaluation of Biodegradable Weed Control Mulch Mats from End-of-Use Cotton Waste

This research used end-of-use cotton apparel to develop mulch mats, a type of agrotextiles. The researchers collected and sorted end-of-use garments to obtain cotton textile waste. These end-of-use garments were deconstructed to obtain shredded textiles and big pieces of textiles. Using the textiles from deconstructed end-of-use garments, together with a small amount of new cotton fibers, the researchers used a Feltloom to develop needle-punched nonwoven fabrics that can be used as mulch mats. The researchers tested textile properties of these mulch mats and conducted agricultural field tests for weed control and pot tests for biodegradation. The researchers also tested the mulch mats’ soil moisture infiltration, and impact on water evaporation. The nonwoven mulch mats made from end-of-use garments have excellent weed inhibition capability and biodegradability. Compared to plastic mulch sheet, the nonwoven mulch mats are better for water utilization in rainfall watering and sprinkle irrigation but poorer in water conservation in drip irrigation. Considering durability, biodegradability, and soil temperature regulation, it is recommended to use 100% cotton and felt four times to produce mulch mats from end-of-use garments.

Sustainable and Robust Cellulose‐Based Core–Shell Hydrogels Recycled from Waste Cotton Fabrics as High‐Performance Food Coolants

AbstractIdeal temperature condition is one of the essential determinants that critically impact the quality of food products. Conventional water‐based ice cubes present challenges from meltwater being breeding grounds for microorganisms and heightening the risk for cross‐contamination. Hereby, the presented cellulose‐based hydrogels crosslinked by epichlorohydrin are dip‐coated with alginate/calcium chloride to form a core–shell structure for achieving the critical benchmarks of an ideal food coolant with limited meltwater production, high‐water retention capacity, and high mechanical strength. The structures and properties of the hydrogels before and after freeze–thaw cycles are characterized by scanning electron microscopy, compressive test, water retention test, and differential scanning calorimetry. All formulated hydrogels demonstrate promising compressive strength, latent heat of fusion, and water retention properties. Notably, the C2A10Cl hydrogel exhibits a maximum compressive strength of 144.7 kPa and high latent heat of fusion of 272.5 J g–1, which is better than previously reported sustainable hydrogel coolants. Furthermore, comparison studies reveal that the cellulose‐based hydrogels demonstrate a similar thawing pattern to conventional ice cubes but without the generation of any meltwater. The temperature of blueberries can be cooled down from 22 to 3.9 °C in 32 min by the hydrogels and in 26 min by ice cubes, respectively.

Tree rings-inspired 3D solar evaporator fabricated by rolling polypyrrole decorated waste cotton fabric for efficient desalination

Interfacial solar steam generation (ISSG) has drawn considerable interest as an emerging technology for seawater desalination. However, designing simple and cost-effective solar evaporators with high salt resistance and impressive evaporation rates remains a significant challenge. Inspired by tree rings, a three-dimensional (3D) solar evaporator (PPy-RWCF) was fabricated by rolling polypyrrole-decorated waste cotton fabric (PPy-WCF) into a cylinder. The synergistic effect of polypyrrole (PPy) and interstices within the waste cotton fabric (WCF) allows the PPy-RWCF to absorb around 99.00 % of sunlight. The PPy-RWCF, with an exposure height of 3 cm, achieves an excellent evaporation rate of 2.36 kg m−2 h−1 under 1-solar intensity. Besides, the vertical water channels within PPy-RWCF allow rapid solution transport, enabling it to withstand 20 wt% brine with an evaporation rate of 2.05 kg m−2 h−1. Prolonged outdoor desalination testing has demonstrated that a 1 m2 PPy-RWCF can generate approximately 10 kg of freshwater daily. This study proposes a sustainable approach to the development of solar evaporators utilizing WCF for desalination of high-salinity water.

Catalytic pyrolysis of plastic waste using activated carbon from cotton waste

This study introduces a novel approach to plastic waste management and energy recovery by synthesizing highly porous activated carbon from an often-overlooked resource, waste cotton fabric (WCF), using H3PO4 as an activating agent. The synthesized waste cotton fabric activated carbon samples (WCF-AC) were utilized as a solid acid catalyst in the catalytic pyrolysis of low-density polyethylene (LDPE), with the aim of converting LDPE into fuel-range hydrocarbons. This research highlights the potential of bio-based waste materials in the synthesis of eco-friendly and cost-effective catalysts for feedstock recycling. The impact of the H3PO4 impregnation ratio and the carbonization/activation temperature on the physicochemical properties of the resulting WCF-AC samples was investigated, providing valuable insights into the optimization of activated carbon production. The catalytic activity of the synthesized WCF-AC samples was evaluated, demonstrating a reduction of 12°C in the LDPE degradation temperature. Furthermore, this work revealed a substantial increase in the formation of carbocyclic compounds, with light aromatics such as benzene, toluene, and xylene constituting up to 43 % of the pyrolysis output. In certain instances, a decrease in heavier hydrocarbons beyond C11 was observed, indicating the selective yield of specific range hydrocarbons. This study underscores the potential of bio-based acid catalysts, such as the synthesized activated carbon presented here, in plastic recycling. The approach adopted in this research aligns with the principles of the circular economy, promoting resource efficiency and sustainability.

Enhanced removal of tetracycline in light-dark tandem by FeCu-doped carbon composites derived from waste cotton fabrics

It is of great significance to develop an energy-efficient and external oxidant-free strategy for antibiotics removal. In this study, the novel light-dark tandem strategy was established to enhance tetracycline (TC) removal by bifunctional FeCu-doped carbon composites (FeCu@BC) derived from waste cotton fabrics. Interestingly, over 95 % TC was removed by FeCu@BC under light alone and dark alone in 10 min, with the same preferred conditions of pH 7.50 and 0.04 g/L catalyst dosage. Surprisingly, the enhanced mineralization efficiency of TC was achieved by the light-dark tandem without adjusting the parameters as 86.65 %, which was 1.13, 1.46 and 2.12 times higher than those of the dark-light tandem, light alone and dark alone, respectively. The mechanisms were elucidated as that 83.28 % direct degradation and 4.37 % indirect degradation under light while 47.63 % direct degradation and 24.16 % indirect degradation under darkness contributed for TC removal. The synergetic effects of persistent free radicals (PFRs) and FeCu interactions enabled FeCu@BC to work efficiently under both light and darkness, and light enhanced electron transfer between PFRs and FeCu interactions. Furthermore, energetic electrons stored in these active sites under light could be extracted to enhance electron transfer under subsequent darkness and the strongly catalytically active species initiated under light remained in action after cessation of light. Finally, high molecular TC was easily decomposed by energetic photo-catalysis and low molecular intermediates were mineralized under subsequent enhanced dark-catalysis to increase the mineralization efficiency. In general, this study provided an eco-friendly organics removal strategy and mechanisms insights based on the natural day-night cycle.

Chromium-extracted aluminum catalyst for co-pyrolysis of cotton fabric waste and polypropylene plastic waste to bio-oil

Heterogeneous catalysts of chromium-extracted aluminum (CE) were prepared and used to produce bio-oil from the co-pyrolysis of cotton fabric waste (CFW) and polypropylene waste (PPW). The catalysts were synthesized via wet impregnation at 5–20 wt% catalyst loading and calcined at 600 °C for 5 h. The co-pyrolysis was conducted in a fixed-bed reactor at 500 °C for 1 h with 1:1 CWF/PPW ratio and 1:1 catalyst/feedstock ratio. The physical and chemical properties of the catalysts and bio-oil were characterized by several techniques such as Brunauer–Emmet–Teller, scanning electron microscopy, energy dispersive x-ray spectroscopy, x-ray diffraction, temperature-programmed desorption and gas chromatography-mass spectrometry. Investigations into the effects of metal loadings revealed that the 15CE catalyst was the most active, achieving a maximum bio-oil yield of 76.4 % and producing valuable chemical compounds like hydrocarbons, alcohols, phenols, and furans. The XRD of 15CE catalyst confirmed the presence of chromium oxide and assigned to the rhombohedral phase of the crystal lattice. BET indicated 15CE has the largest surface area (50.4 m2/g) among the CE catalysts which contributed to its high activity. The SEM revealed CE catalysts at different metal loadings contain irregular shapes and sizes with a rough surface texture. The NH3-TPD profiles indicated alterations in acid site distribution due to the interaction between the introduced Cr metal and EA. The 15CE catalyst also demonstrated significant reusability, maintaining performance after two regeneration cycles. These results confirm the potential of CE catalysts in enhancing bio-oil production from CFW and PPW.

High tensile regenerated cellulose fibers via cyclic freeze-thawing enabled dissolution in phosphoric acid for textile-to-textile recycling of waste cotton fabrics

Recycling of waste cotton fabrics (WCFs) is a desirable solution to address the problems brought up by fast fashion, but it remains challenging due to inherent limitations in preparing stable and spinnable dopes by dissolving high molecular weight cellulose efficiently and cost effectively. Herein, we show that despite the prevailing concerns of cellulose degradation via glycosidic hydrolysis when dissolved in acids, fast and non-destructive direct dissolution of WCFs in aqueous phosphoric acid (a.q. PA) could be realized using a cyclic freeze-thawing procedure, which combined with subsequent adjustment of degree of polymerization (DP) and degassing yielded stable and spinnable dopes. Regenerated cellulose fibers (RCFs) with favorable tensile strength (414.2 ± 14.3 MPa) and flexibility (15.4 ± 1.5 %) could be obtained by carefully adjusting the coagulation conditions to induce oriented and compact packing of the cellulose chains. The method was shown to be conveniently extended to dissolve reactively dyed WCFs, showing great potential as a cheap and green alternative to heavily explored ionic liquids (ILs) and N-methylmorpholine-N-oxide (NMMO)-based systems for textile-to-textile recycling of WCFs.

A regenerated cellulose fiber with high mechanical properties for temperature-adaptive thermal management

The escalating global population has led to a surge in waste textiles, posing a significant challenge in landfill management worldwide. In this work, ionic liquid 1-butyl-3-methylimidazole acetate ([Bmim]OAc) and DMF (N, n-dimethylformamide) were used as solvents to dissolve waste denim fabric, then vanadium dioxide (VO2) nanoparticles were introduced into the spinning solution, and cellulose fibers were regenerated by dry-wet spinning process, to promote the recycling of waste cotton fabric. Finally, regenerated cellulose fibers with high added value were prepared by dry-wet spinning. Through this innovative strategy, on the one hand, because VO2 can form a large number of hydrogen bonds between the regenerated cellulose molecules, and realize the cross-networking structure of the molecular chains inside the fiber, the mechanical properties of the regenerated cellulose fibers are enhanced. On the other hand, due to the thermal phase transformation characteristics of VO2, it also endows the regenerated cellulose fiber unique intelligent temperature control function. Compared with the pristine regenerated fiber, the tensile stress of the regenerated fiber after adding VO2 nanoparticles (F-VO2) increased by 25.6 %, reaching 158.68 MPa. In addition, the F-VO2 fibric provides excellent intelligent temperature control, reducing temperatures by up to 6.7 °C.

Preparation of Al-doped carbon materials derived from artificial potassium humate prepared from waste cotton cloth and their excellent Cr(VI) adsorption performance

Millions of tons of cotton textile waste are generated annually worldwide, and most of it enters the municipal solid waste (MSW) stream for landfill or incineration disposal, resulting in a significant waste of resources and environmental pollution. This article developed an innovative low-temperature pyrolysis process for producing artificial humic acid (HA) from waste cotton textiles. Subsequently, Al3+ was introduced for a secondary pyrolysis to prepare an Al-doped biochar (Al/BC) with superior adsorption properties. The experimental results show that the presence of Al3+ has an important influence on the pyrolysis process of cotton fabric and the formation and structure of Al/BC. This is the first time to synthesize low-cost adsorbent by pyrolysis and aluminum mixing process of waste cotton cloth and explains the mechanism. This increased in defects (ID/IG = 0.76 to ID/IG = 0.92), a larger specific surface area (6.47 m2/g to 566.94 m2/g), and an increase in oxygen-containing functional groups (from none to C-O-C, OC-O, etc.) when compared to the undoped Al3+ biochar. The optimum Al3+-doped biochar (Al/BC-15) prepared with HA as a precursor exhibited a superior adsorption capacity for Cr(VI) of up to 176.23 mg/g, surpassing the results reported for similar materials in the literature. The adsorption mechanism of Cr(VI) is primarily based on physical adsorption, with some chemical adsorption. At a lower pH, the Al/BC-15 surface exhibits a high positive charge (46 mV). The Al3+-O-Cr(VI) association group is formed through rapid electrostatic attraction between C-Al and Cr(VI). Due to the strong positive electronegativity of Al3+ and the negative electronegativity of C in the vicinity of Al, Cr(VI) is further reduced to Cr(III) by C-Al. Therefore, the method proposed in this paper for preparing Al-doped carbon materials from waste cotton fabric offers a new approach and potential application for the production of high-performance adsorbent materials from waste cotton fabric.

Added-Value of Cotton Textile Waste for Nonwoven Applications

Due to the continuous optimization of cutting plans, the cotton scrap size resulting from the cutting of components for clothing production (post-industrial residues) is often considered insufficient to obtain fibres with the proper length to produce a new yarn through mechanical recycling processes; so it is important to search for other applications for these wastes. In this context, small pieces of cotton were submitted to a shredding process to obtain recycled fibres. Cotton small pieces and recycled fibres were then submitted to a refining process to achieve refined fibres. Using these materials alone and in blends with refined and unrefined bleached eucalyptus kraft pulp (BEKP), wet-laid nonwovens were developed and characterized. An analysis of the results revealed that the replacement of unrefined BEKP by 70% cotton waste fibres in wet-laid nonwovens, reducing the use of virgin raw material, enhances the structures’ mechanical properties by 80% and 14%, for small pieces or recycled fibres, respectively. Additionally, refining small pieces of cotton seems to be more promising than refining recycled fibres, because less steps are required to obtain wet-laid nonwovens with better mechanical properties. These results highlight the potential of this approach to be explored further for different products and end applications.

Production and Characterization of Recycled Polypropylene Composite Reinforced with Cotton Fabric Waste

Composite materials have played an important role throughout human history, from housing early civilizations to enabling future innovations. This study explores the development of composite materials from recycled polypropylene and cotton fabric waste targeted for different applications. The composites were manufactured by the melt-mixing method. The effects of cotton fabric waste content on various composite characteristics were investigated using tensile strength, tensile modulus, flexural strength, flexural modulus, impact strength, compressive strength, and water absorption. The study showed that with an increase in cotton fabric waste content, properties such as tensile strength, tensile modulus, flexural strength, flexural modulus, impact strength, and compressive strength increase up to the optimum level, while a decrease in these properties is observed after the optimal level. The maximum tensile strength of 57.84 MPa, tensile modulus of 1.31 GPa, flexural strength of 55.32 MPa, flexural modulus of 2.7 GPa, impact strength of 33.06 kJ/m2, and compressive strength of 53.68 MPa were obtained. The water absorption rate increased with an increase in the cotton fabric waste weight proportion. From the result of this study, it can be concluded that the optimal mechanical and water absorption properties were achieved at 30% cotton fabric waste content. Therefore, creating composites from recovered polypropylene and cotton fabric waste can have both environmental and financial benefits.

Design and Fabrication of Multifunctional E-Textiles by Upcycling Waste Cotton Fabrics through Carbonization

The merging of electronic materials and textiles has triggered the proliferation of wearables and interactive surfaces in the ubiquitous computing era. However, this leads to e-textile waste that is difficult to recycle and decompose. Instead, we demonstrate an eco-design approach to upcycle waste cotton fabrics into functional textile elements through carbonization without the need for additional materials. We identify optimal parameters for the carbonization process and develop encapsulation techniques to improve the response, durability, and washability of the carbonized textiles. We then configure these e-textiles into various 'design primitives' including sensors, interconnects, and heating elements, and evaluate their electromechanical properties against commercially available e-textiles. Using these primitives, we demonstrate several applications, including a haptic-transfer fabric, a joint-sensing wearable, and an intelligent sailcloth. Finally, we highlight how the sensors can be composted, re-carbonized and coated onto other fabrics, or repurposed into different sensors towards their end-of-life to promote a circular manufacturing process.

Consecutive high-performance removal of Cu2+ metal ions and Deltamethrin using multifunctional pyrolysis cuttlebone/cotton fabric nanocomposite

A simple technique was developed for the modification of cotton materials that is inexpensive, environmentally friendly, and very effective. Waste Cotton fabrics (WCFs) are loaded with propolis extract (PE) for Cu2+ removal. Then, Cu2+ underwent a pyrolysis process with modified cuttlebone (CB) at 900 °C for 5 h. The surface of the prepared materials was characterized using X-ray diffraction (XRD), scanning electron microscopy with energy-dispersive X-ray (SEM-EDX), Fourier transform infrared (FTIR), BET, particle sizes, thermogravimetric analysis (TGA) and zeta potential analysis. The Cu2+ metal ions from an aqueous solution were removed using WCFs/PE, and DLM was subsequently removed using pyro WCFs/PE/Cu/CB. The as-prepared NPs exhibited the face-centered cubic structure of WCFs/PE/Cu/CB with crystallite sizes ranging from 386.70 to 653.10 nm. FTIR spectra revealed that CB was present on the surface of the resulting WCFs/PE/Cu. SEM revealed the dispersion of a uniformly flower-like morphology over a large area. Sorption studies were performed based on parameters that included pH, dose, contact time, and initial concentration. The adsorption isotherm and the kinetic studies of the DLM adsorption process were applied at a pH of 5.0 and a temperature of 25 °C using several isotherms and kinetic models. The results revealed qmax (20.51 mg/g) with R2 = 0.97, the Langmuir isotherm that best matches the experimental data. Hence, the Langmuir isotherm suggests that it is the model that best describes sorption on homogenous surfaces or surface-supporting sites with various affinities. The correlation coefficient R2, χ2, adjusted correlation coefficient, and error functions like root mean square (RMSE), normalized root mean square error (NRMES), and mean absolute error (MAE) were used to evaluate the best-fit models to the experimental adsorption data. Moreover, cost estimation for the prepared adsorbent WCFs/PE/Cu showed that it costs approximately 3 USD/g, which is a cheap adsorbent compared to other similar adsorbents reported in the literature. The examined WCFs/PE have significant applicability potential for Cu2+-laden wastewater treatment due to their superior Cu2+ metal ions adsorption capability and reusability.The cytotoxicity and safety study showed that at higher concentrations, it resulted in much less cell viability. Additionally, the removal efficiency of Cu2+ metal ions from synthetic, realistic industrial wastewater using WCFs/PE reached up to 96.29 %, demonstrating good adsorption capability. Thus, there is a huge possibility of accomplishing this and performing well. This study paves the way for the reuse and valorization of selected adsorbents following circular economy principles.Two green metrics were applied, the Analytical Eco-scale and the Analytical GREEnness Calculator (AGREE).

Double-layered cellulosic interfacial evaporator via upcycling of waste cotton fabrics for efficient solar desalination

Constructing efficient solar-driven interfacial evaporators (SDIEs) derived from biomass or waste stream materials (e.g., cellulose) is still challenging due to their less elaborate porous structure. Herein, we showed waste cotton fabrics could be dissolved and regenerated into aerogels with tunable channels suitable for constructing a double-layered SDIE. The evaporator consists of a polypyrrol-coated top layer featuring vertical channels with larger pores and a hydrophilic bottom layer featuring smaller pores. With such design, the photothermal and pro-evaporative capabilities of the top layer was coupled with the strong capillary effect of the bottom layer to drive effective evaporation. A desirable evaporation rate of 3.20 kg m−2h−1, 80.0% solar-to-vapor conversion efficiency under 1 sun irradiation, and a reduced evaporation enthalpy of 962 J g−1 was achieved. The SDIE also exhibits high purification efficiency (exceeding 99%) during long-term operation of seawater desalination and shows great potential in treatment of waste streams of high salinity dyeing effluent. In summary, this work demonstrates a case of upcycling waste cotton fabrics for water desalination.