Composite fiber of polyvinyl alcohol/activated carbon from corn cob prepared by electrospinning as a sustainable adsorbent for efficient rhodamine B adsorption

Rhodamine B (RB) is a synthetic dye commonly used in the textile industry, but its presence poses risks to health and the environment. Mitigating water pollution caused by synthetic dyes necessitates effective wastewater treatment methods. Therefore, this study aims to develop a simple, cost-effective, and environmentally friendly approach to synthesizing adsorbents by combining polyvinyl alcohol (PVA) and corn cob (CC)-based activated carbon (AC) through an electrospinning process to form PVA/AC composite fibers. The results showed that the increase in AC content in the composite fiber led to an enhancement in the adsorption performance against RB. PVA/AC composite fiber containing 10 % AC had a maximum adsorption capacity 5.41 times higher than PVA fiber and got a maximum 96.02 % RB removal efficiency. Adsorption isotherm analysis demonstrated compliance with the Langmuir model. Kinetic studies show that the pseudo-first-order (PFO) model best explains the adsorption process. Thermodynamic analysis also indicated that the adsorption was spontaneous and exothermic (ΔH° = −57.23 kJ/mol). Based on reusability tests, the adsorbent maintained a high removal efficiency, with RB removal decreasing marginally from 96.35 % to 78.93 % after five cycles. These results underscore the potential of PVA/AC composite fiber as an effective adsorbent for addressing water pollution caused by synthetic dyes.