Jute-waste-derived cellulose fiber reinforced hydrogel composites for the removal of crystal violet from aqueous media.

Sustainable adsorbents derived from renewable biomass have emerged as promising materials for wastewater treatment. In this study, a cellulose fiber-reinforced hydrogel (CF-RH) composite was developed from jute waste and employed for the removal of crystal violet (CV) dye from aqueous solutions. Cellulose fiber (CF) was extracted from the waste jute fibers (JF) through bleaching and alkali treatment and subsequently incorporated into a polyacrylamide (PAAm) hydrogel matrix. The PAAm hydrogel was synthesized via crosslinking polymerization using N,N-methylene bisacrylamide and potassium persulfate. The CF-RH composite was subsequently prepared by dispersing CF into the hydrogel precursor solution prior to polymerization. The resulting CF, PAAm hydrogel and CF-RH composite were characterized by various techniques such as Fourier transform infrared spectroscopy, X-ray powder diffraction, field-emission scanning electron microscopy with energy-dispersive X-ray spectroscopy, transmission electron microscopy, and dynamic light scattering. To evaluate the effects of adsorbent dosage, initial dye concentration, contact time, solution pH, and mechanical stirring on CV removal, batch adsorption experiments were conducted. The CF-RH composite exhibited substantially higher adsorption performance compared to the pristine PAAm hydrogel. The equilibrium adsorption data were best fitted by the Langmuir adsorption isotherm model, yielding a maximum adsorption capacity of 196 mg g-1. Kinetic studies demonstrated that the adsorption process was best described by the pseudo-second-order model, indicating that the adsorption rate was strongly associated with the availability and interactions of adsorption sites. Thermodynamic data reveals that the adsorption process is spontaneous. Notably, the CF-RH composite exhibited good reusability, preserving more than 94% of its initial adsorption capacity for five consecutive cycles. The enhanced adsorption performance and regeneration capacity of the CF-RH composite are attributed to the synergistic interaction between the CF and PAAm matrix. Overall, the jute-waste-derived CF-RH composite represents a low-cost, reusable, and sustainable adsorbent for removal of CV dye from aqueous solution, highlighting its potential for wastewater treatment applications.