Colour removal from textile effluents by adsorption techniques

The adsorption of two basic dyestuffs (Atrazon Blue and Maxilon Red) and two acid dyestuffs (Telon Blue and Erionyl Red) onto maize cob was studied. High adsorptive capacities were observed for the adsorption of basic dyestuffs, namely, 160 and 94.5 mg dye per g maize cob for Astrazon Blue and Maxilon Red, respectively. Lower capacities were obtained with the acid dyestuffs, namely, 47.7 and 41.4 mg dye per g maize cob for Erionyl Red and Telon Blue, respectively. A series of contact-time experiments was undertaken in an agitated batch adsorber to assess the effect of the system variables, namely, agitation speed, maize cob particle size and maize cob mass. The experimental results for these contact-time experiments were discussed.