Decolorization of synthetic dye wastewater using packed bed electro-adsorption column

Abstract

The present study reports the electro-adsorption of Methylene blue (MB) dye from synthetic wastewater onto activated carbon in a packed bed electro-adsorption column and the break through data was analyzed for dye adsorption. The influences of bed height, flow rate and initial dye concentration with and without the presence of electrical potential on packed bed adsorption have been investigated and the possibility of regeneration of column was studied. The parameters such as bed capacity, mass transfer zone, bed utilization and adsorbent usage were evaluated from the break through curves. The columns characteristic design parameters have been evaluated using the adsorption models such as Bed Depth Service Time (BDST), Adam-boharts, Thomas and Yoon-Nelson models. The model parameters have been derived using origin software. Out of four adsorption models, Thomas and Yoon-Nelson models were found to be ideal to analyze the column performance with R2 ≥ 0.80. From the results, it is observed that electro-adsorption is more efficient than adsorption as the adsorption capacity is 3.18 folds higher and the amount of adsorbent required was much lesser for electro-adsorption. Also the saturation capacity is 0.17 mg/g for electro-adsorption whereas it is 0.069 mg/g for conventional adsorption at optimized condition, which confirms the stability of electro-adsorption column. It has been observed that modifications in electrode played a major role in dye waste water treatment processes.