Adsorption of reactive dyes from a textile effluent using sawdust as the adsorbent

Adsorption is carried out for the removal of two reactive dyes from an industrial effluent. The specific dyes are reactive red and reactive black, commercially known as Cibacron Red RB and Cibacron Black B, respectively. An adsorbent developed from sawdust is used. Equilibrium and kinetic studies are carried out with the synthetic solutions of the dyes. For the mixture of two dyes, the bisolute Langmuir isotherm modified with an interaction factor is used. A mass transfer model including an external film mass transfer coefficient and an internal effective diffusivity is used to interpret the adsorption kinetic data. These parameters are obtained by fitting the experimental data to the model. An industrial effluent is successfully treated with the same adsorbent. The estimated model parameters are used for the prediction of the concentration profiles of dyes of the industrial effluent.