Abstract
Low-cost teak leaf litter powder (TLLP) was prepared as possible substitute for activated carbon. The feasibility of using the adsorbent to remove eosin yellow (EY) dye from aqueous solution was investigated through equilibrium adsorption, kinetic and thermodynamic studies. The removal of dye from aqueous solution was feasible but influenced by temperature, pH, adsorbent dosage and contact time. Variation in the initial concentration of dye did not influence the equilibrium contact time. Optimum adsorption of dye occurred at low adsorbent dosages, alkaline pH and high temperatures. Langmuir isotherm model best fit the equilibrium adsorption data and the maximum monolayer capacity of the adsorbent was 31.64 mg g−1 at 303 K. The adsorption process was best described by pseudo-second order kinetic model at 303 K. Boundary layer diffusion played a key role in the adsorption process. The mechanism of uptake of EY by TLLP was controlled by both liquid film diffusion and intraparticle diffusion. The values of mean adsorption free energy, E (7.91 kJ mol−1), and standard enthalpy, ΔH° (+13.34 kJ mol−1), suggest physical adsorption. The adsorption process was endothermic and spontaneous. Teak leaf litter powder is a promising low-cost adsorbent for treating wastewaters containing eosin yellow.
Highlights
Eosin yellow (EY) is an anionic xanthen dye which is widely used for producing ink, pharmaceutical and textile products[6]
This study investigated the practicability of using low-cost adsorbent from teak leaf litter for removing eosin yellow (EY) in aqueous solution
The low surface area and iodine number of the adsorbent culminates in its low activity level
Summary
Eosin yellow (EY) is an anionic xanthen dye which is widely used for producing ink, pharmaceutical and textile products[6]. Commercial activated carbon and graphene are expensive, possess poor selectivity properties and require expensive regeneration after their adsorptive power is exhausted[12]. These challenges prompted researchers to investigate effective and cheaper adsorbents as substitutes for these materials. The materials were adjudged to possess high capacity, high selectivity, low energy-consuming regeneration, low toxicity, high versatility and moderate cost among other benefits They were converted into 3D hydrogel network and applied to smart assembly systems with great success. They have been touted to pave way for better and cheaper treatment of dye-contaminated wastewaters, environmental remediation and selective extraction. The veracity of these claims cannot be independently established until the materials are available for use commercially
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
