Removal of reactive dye from aqueous solution by activated carbon

Abstract

This study investigates the potential use of activated carbon prepared from orange peel for the removal of remazol brilliant blue R (RBBR) dye from aqueous solution. The effects of different system variables, solution pH (from 4 to 10), solution temperature (from 25 to 55 °C), adsorbent dose (from 0.1 to 1 g) and contact time (from 15 to 75 min) were studied. The maximum dye removal was reached at 75 min. The results showed that as the amount of the adsorbent increased, the percentage of dye removal increased accordingly. Sorption isotherms were analyzed by Langmuir, Freundlich, Redlich-Peterson, Tempkin and Dubinin-Radushkevich models at different temperatures of 25, 35, 45 and 55 °C. The maximum adsorption capacity obtained from Langmuir equation was 26.15 mg g-1. Furthermore, adsorption kinetics of remazol brilliant blue R were studied and the rate of adsorption was found to conform to pseudo-second-order kinetics with a good correlation (R2 > 0.85) with intraparticle diffusion as one of the rate determining steps. The results of this study showed that activated carbon developed from orange peel could be employed as effective and low-cost materials for the removal of dyes from aqueous solution.