A kinetic study of dye sorption by biosorbent waste product pith

The sorption of two dyes, namely, Basic Red 22 and Acid Red 114 onto pith has been studied in terms of pseudo-second-order, pseudo-first-order sorption and intraparticle diffusion processes thus comparing chemical sorption and diffusion sorption processes. The pseudo-second-order model. based on the assumption of a pseudo-second-order mechanism, has been developed to predict the rate constant of sorption, the equilibrium capacity and initial sorption rate as a function of the effect of initial dye concentration, pith particle size, pith dose and temperature. (C) 1999 Elsevier Science B.V. All rights reserved.