Eucalyptus leaf powder as an efficient scavenger for Congo red from water: Comprehensive batch and column investigation

Abundantly available Eucalyptus leaf (Eucalyptus globulus) was investigated as promising bio-sorbent for removal of Congo red by batch and column method. Material was characterized by proximate analysis, SEM-EDS, FT-IR, BET, XRD, and chemical analysis. Physico-chemical parameters like contact time, dose, and pH were optimized. Maximum adsorption capacity is 29.68 mg/g. Adsorption follows intraparticle diffusion kinetics (K = 0.211 mg/g/min^0.5, R² = 0.996) and Freundlich isotherm model (R² = 0.996). Thermodynamic study revealed a spontaneous and feasible process (ΔG = – 13.06 kJ/mol). Regeneration (82%) with dilute alkali enables multicycle use. Column breakthrough follows Thomas and BDST model. Cost-benefit analysis suggests economically sustainable material for dye decolorization.