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 h as been studied in terms of pseudo-second-order, pseudo-first-order sorptio n and intraparticle diffusion processes thus comparing chemical sorption an d diffusion sorption processes. The pseudo-second-order model. based on the assumption of a pseudo-second-order mechanism, has been developed to predi ct the rate constant of sorption, the equilibrium capacity and initial sorp tion rate as a function of the effect of initial dye concentration, pith pa rticle size, pith dose and temperature. (C) 1999 Elsevier Science B.V. All rights reserved.