| Abstract: | The present work investigated the biosorption of nickel from synthetic and electroplating industrial effluents using a green marine algae Ulva reticulata. Preliminary batch results imply that pH 4.5 was optimum for nickel uptake and the isotherm experiments conducted at this pH condition indicated that U. reticulata can biosorb 62.3 mg g–1 nickel ions from synthetic solutions, according to the Langmuir model. Desorption was effective and practical using 0.1 M CaCl2 (pH 2.5, HCl) and the biomass was regenerated and reused for three cycles. Continuous biosorption experiments were performed in an upflow packed column (2 cm I.D and 35 cm height). Among the two electroplating effluents used, effluent‐1 is characterized by excess co‐ions and high nickel ion content. This influenced the column nickel uptake with U. reticulata exhibiting 52.1 mg g–1 in the case of effluent‐1 compared to 56.5 mg g–1 in the case of synthetic solution. On the other hand U. reticulata performed well in effluent‐2 with uptakes of 53.3 and 54.3 mg g–1 for effluent‐2 and synthetic solution, respectively. Mathematical modeling of column experimental data was performed using nonlinear forms of the Thomas‐ and modified dose‐response models, with the latter able to simulate breakthrough curves with high correlation coefficients. |
