This thesis investigated the continuous adsorption of methylene blue (MB) onto calcium alginate/graphene oxide (Ca-Alg/GO) hydrogel beads in a packed bed column. Six experiments were carried out with systematic variation of flow rate (Q = 1, 3 and 5 mL/min), inlet MB concentration (C$_0$ = 2, 5 and 10 mg/L) and bed height (Z = 4.2 and 8.4 cm), at a constant column inner diameter (D = 9.6 mm) and bead diameter (d$_p$ = 2.405 mm). The MB concentration in the column effluent was determined spectrophotometrically at 665 nm using an experimentally derived calibration equation (slope 0.2114 L/mg, R$^2$ = 0.9992). Mass balance parameters including specific capacity, stoichiometric time, mass transfer zone length and empty bed contact time were calculated from the experimental breakthrough curves by numerical integration. The data were fitted to four empirical models: Thomas, Yoon-Nelson, Yan (dose-response) and the diffusion-based (erfc) model. The Thomas and Yoon-Nelson models were numerically confirmed to be mathematically equivalent. The Yan model consistently achieved better goodness of fit (R$^2$ = 0.71-0.90) than the Thomas model (R$^2$ = 0.30-0.71), as it correctly predicts zero effluent concentration at the start of the experiment. Dimensionless analysis (Re, Sc, Sh, Bi), based on an assumed effective diffusion coefficient, indicated that intraparticle diffusion through the alginate/GO network is likely the rate-limiting step (Bi ≫ 1). The two-stage film-diffusion model achieved the highest R$^2$ values (0.91–0.95) but was found to be structurally underdetermined within the experimental time window, as the slow intraparticle diffusion regime operates on a time scale significantly longer than the duration of individual experiments.
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