The adsorption performance, kinetics, and thermodynamic parameters of reactive dyes on chitosan-treated cotton fabric are described in this research. The batch experiment was carried out to investigate the influence of pH, time, temperature, dye concentration, and material to liquid ratio of Remazol Red RR and Remazol Yellow RR, two widely used reactive dyes. The adsorption of red and yellow dyes was observed at λmax 517 and 419 nm respectively. For both Remazol Red RR and Remazol Yellow RR reactive dyes with starting dye concentrations of 0.0667 and 40 mg/L, the greatest dye adsorption was reported at pH 11 (0.0009 and 0.1284 mg/g) and pH 4 (0.0004 and 0.1038 mg/g). The adsorption performance was investigated using the Langmuir and Freundlich isotherms. The adsorption behaviours of the two reactive dyes closely matched to the Langmuir adsorption isotherm (R2>0.98) than Freundlich isotherm (R2>0.92). The pseudo-second-order kinetic model (R2>0.99) was followed by the dyeing kinetics of modified cotton sample. Thermodynamic investigation was covered with enthalpy change (ΔH⁰), Gibbs free energy (ΔG⁰) and entropy change (ΔS⁰) where all the values were reported positive confirming that the adsorption process was non-spontaneous, endothermic and the higher affinity of reactive dye on chitosan treated cotton.

Activated carbon (AC) fiber is a carbonaceous material with a porous structure that has a tremendous scope of application in different fields. Conventionally, AC is derived from fossil fuel-based raw materials like polyacrylonitrile (PAN) and pitch. In this work, AC was synthesized from eco-friendly, renewable, and ubiquitous jute fiber. Systematically, the jute fiber was washed and pretreated with NaOH. Raw jute and NaOH-treated jute were carbonized/pyrolyzed at 500 °C for 1 h in presence of N₂ gas. The carbonized carbon was activated with H₃PO₄ and KOH and again pyrolyzed at 650 °C for 1.5 h maintaining the inert condition. The different features of activated carbons were characterized with field emission-scanning electron microscope, energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), X-ray diffraction (XRD), and thermogravimetric analysis. The average yield of carbonized and activated carbons was recorded at 19 and 13.8%, respectively. The scanning electron microscopic images confirmed a honeycomb-like porous structure. It was observed that KOH-activated carbon exhibited a more porous structure than the H₃PO₄-activated carbons. The average pore diameter of activated carbons was noted to be 1.3 μm. The pore density was higher in case of KOH-activated carbons accounting for 2.15 pore/μm. The EDX analysis showed that H₃PO₄-activated carbons had more than 90% carbon atoms indicating a significant carbon content. The TEM images revealed that AC particles were in the nanoscale range. The average particle sizes of H₃PO₄-activated carbon and KOH-activated carbon were 36.38 and 32.8 nm, respectively. The XRD study demonstrated the highly disordered and low level of crystallinity of AC. It was detected that the AC showed much higher thermal resistance than the jute fiber. The H₃PO₄-activated carbon obtained from NaOH-treated jute remained at 84% even after 500 °C. A higher thermal resistance was achieved with H₃PO₄-activated carbon since it contains 0.56% phosphorus, which was confirmed by EDX investigation. It was found that a higher carbon yield was obtained from NaOH-treated jute. The porous structure of the material showed that it could be used as an adsorbent. Due to its high thermal stability, it is recommended for flame retardants and heat insulation applications as well.

The utilization of natural dyes in textile production has gained significant attention due to their eco-friendly characteristics and minimal environmental impact. Serving as a sustainable alternative for textile coloring, particularly when derived from native plant species, natural dyes contribute to the promotion of local biodiversity. Obtained from various botanical sources such as flora, flowers, leaves, roots, berries, barks, and wood, they offer a diverse range of hues spanning blues, reds, yellows, browns, and violets. However, achieving consistent and predictable colors with natural dyes presents challenges due to inherent variations in plant sources, growing conditions, and extraction techniques. The integration of mordants, including aluminum potassium sulfate, potassium dichromate, copper sulfate, and others, is crucial to enhance dye absorption and improve colorfastness. Natural dyes are employed across fabrics like cotton, linen, silk, wool, hemp, and blends, each contributing unique qualities to the vibrant and environmentally friendly palette. Yet, the longevity and strength of colors may vary based on factors like dye type, fabric substrate, and mordant effects, impacting chemical bonding between fibers, dyes, and mordants. Hence, meticulous selection of dyes and mordants, considering their compatibility with specific fibers, is essential for achieving optimal colorfastness and durability in natural dyeing processes.

This study presents an eco-friendly flame-retardant solution for cellulosic fabrics using green coconut shell (GCS) extract and phytic acid (PA). Cellulosic materials are highly flammable and release harmful gases during combustion. Conventional flame retardants may pose environmental and health risks while impacting the fabric quality. GCS extract is a rich source of tannins, phosphorus, silicates, metallic salts, and oxides and is explored as a novel flame retardant (FR) for cotton fabrics. Cotton samples were pretreated with PA and then with varying concentrations of GCS extract using a padding technique. Comprehensive characterization followed, including limiting oxygen index (LOI), thermogravimetric analysis (TGA), derivative thermogravimetry (DTG), burning time tests, scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) analysis, Fourier-transform infrared spectroscopy (FTIR), tensile strength, and wash durability assessments. The treated samples exhibited improved flame resistance properties, with LOI values increasing from 18 to 29.5. TGA results indicated enhanced thermal stability, while FTIR analysis confirmed higher phenolic hydroxyl content in treated samples. SEM imaging verified GCS extract deposition and EDX analysis revealed key elements such as Na, Al, P, S, K, and Ca on the treated surfaces. The combination of GCS extract and PA offered a sustainable and effective flame-retardant solution for cellulosic fabrics. The naturally sourced elements help to enhance fire resistance while preserving environmental and material integrity.