Comparison of methylene blue adsorption from aqueous solution using spent tea dust and raw coir pith

Abstract

The purpose of the present work is to test the possibility of using the spent tea dust and raw coir pith for the removal of methylene blue (MB) from aqueous solution. The effects of the contact time, adsorbent dosage and solution pH were studied in batch experiments at 27 °C. Results showed that a pH of 7 is favourable for the adsorption of dye. The isothermal data could be well described by the Langmuir equations. Kinetic parameters of adsorption such as the Langergen pseudo-first-order, pseudo-second-order rate constant and the intraparticle diffusion rate constant were determined. The adsorption capacities of Spent Tea Dust (STD) and Raw Coir Pith (RCP) were found to be 86.21 mg and 142.86 mg g-1 of the adsorbent respectively. The results indicate that STD and RCP could be employed as low-cost alternatives to commercial activated carbon for the removal of dyes from aqueous solution. © 2014 Global NEST Printed in Greece. All rights reserved.