From Invasive Pest to Environmental Solution: Chemical Activation of Egyptian Water Hyacinth for Sustainable Textile Dye Remediation

The proliferation of water hyacinth (Eichhornia crassipes), an invasive aquatic macro-phyte, poses significant environmental challenges to water bodies globally. This study investigates the valorization of this problematic biomass into a sustainable adsorbent for dye removal from aqueous solutions. Water hyacinth was subjected to chemical activa-tion using sulfuric acid at varying concentrations to evaluate its adsorption efficacy for methylene blue (cationic dye) and Ponceau S (anionic azo dye). The performance was benchmarked against conventional adsorbents including rubber and wood. Spectro-photometric analysis revealed that water hyacinth activated with concentrated sulfuric acid achieved removal efficiencies exceeding 90% for methylene blue and 99.4% for Ponceau S, substantially outperforming both rubber (77%) and wood (9%). Elazab et al. reported 90% methylene blue removal using cobalt nanoparticle-enhanced water hya-cinth carbon, whereas our unmodified, diluted acid-activated biomass achieved 98% removal without metal nanoparticles. Notably, diluted acid activation demonstrated comparable efficacy with removal rates of 98% and 82% for methylene blue and Ponceau S, respectively. These findings underscore the dual benefit of mitigating water hyacinth invasion while providing an eco-friendly, cost-effective solution for textile wastewater treatment. The comparable performance of diluted acid activation suggests a more sus-tainable approach that minimizes environmental impact while maintaining high ad-sorption capacity.