De-colorization of textile wastewater by adsorption in a fluidized bed of locally available activated carbon.

The competency of a locally available granular activated carbon (GAC) in removing color from textile wastewater was studied in a fluidized bed. The characteristics of the fluidized bed with different GAC particles were obtained. A reactive dye was used to prepare the colored water of different dye concentrations. The effects of the GAC particle size, velocity and initial concentration of the colored water on dye removal were investigated. Equilibrium adsorption isotherm and breakthrough curves were generated to determine adsorption characteristics of activated carbon as well as mass transfer coefficients of the fluidized bed. The results of these experiments showed that an increase in liquid velocity and a decrease in particle size increased the color removal. The experiments were also carried out with industrial effluent and the de-colorization achieved was satisfactory. The mass transfer coefficient calculated for the fluidized bed was very low, which suggests that the GAC used in the local industries, although less expensive, may not be economically viable for de-colorization of industrial effluent.