A kinetic study of metal complex dye sorption onto pine sawdust

The removal of metal complex dyes, Metal Complex Blue (MCB) and Metal Complex Yellow (MCY), from aqueous solutions by pine sawdust has been studied in single component sorption systems. The aim of this study was to understand the mechanisms that govern metal complex dyes removal and find a appropriate model for the kinetics of removal in a batch reactor. In order to investigate the mechanism of sorption and potential rate controlling steps, pseuso first- and second-order equations, intraparticle diffusion equation and the Elovich equation have been used to test experimental data. Kinetic analysis of the four models has been carried out for system variables-particle size and mass of sawdust, pH and initial dye concentration. The rate constants for the four models have been determined and the correlation coefficients have been calculated in order to assess which model provides the best fit predicted data with experimental results. Both pseudo second-order equation and the Elovich equation provide the best fit to experimental data. (C) 2004 Elsevier Ltd. All rights reserved.