Adsorption of chromotrope dye onto activated carbons obtained from the seeds of various plants: Equilibrium and kinetics studies

Abstract

The use of low-cost, easily obtained and eco-friendly adsorbents has been employed as an ideal alternative to the current expensive methods of removing dyes from wastewater. This study investigates the potential use of activated carbons such as aamla seed carbon (ASC), jambul seed carbon (JSC), tamarind seed carbon (TSC) and soapnut carbon (SNC) for the removal of chromotrope (CH) dye from simulated wastewater. The obtained results were compared with that of Commercial Activated Carbon (CAC). The effects of different system variables, adsorbent dosage, pH and particle size were studied. The results showed that as the amount of the adsorbent increased, the amount adsorbed per unit mass decreased accordingly. Optimum pH value for dye adsorption was determined as ∼2.0. The adsorption of chromotrope fit well into pseudo-second-order rate equation. The adsorption also obeyed Langmuir and Redlich–Peterson equations better than Temkin, Freundlich and Dubinin–Radushkevich (D–R) equations. The adsorption capacities of low cost adsorbents were found to be in the following order ASC > JSC > TSC > SNC. The activated carbons prepared were characterized by FT-IR and SEM analysis.

Keywords

• Adsorption
• Chromotrope (CH)
• Aamla seed carbon (ASC)
• Jambul seed carbon (JSC)
• Tamarind seed carbon (TSC)
• Soapnut carbon (SNC)
• Commercial activated carbon (CAC)