Abstract
Ethyl violet (EV) is one of the common pollutants in industrial wastewaters. This study presents the kinetic, isotherm and thermodynamic characterization of the adsorptive removal of EV from aqueous solution by used black tea leaves (UBTL) as a low cost adsorbent. Batch adsorption experiments were performed to investigate the effects of initial dye concentration, solution pH and temperature on the adsorption kinetics. Experimental data were evaluated by inspecting the liner fitness of different kinetic model equations such as pseudo-first order, pseudo-second order, Elovich and Intra-particle diffusion models. The equilibrium amounts adsorbed at different equilibrium concentrations were determined from well fitted pseudo-second order kinetic plot to construct the adsorption isotherm. The maximum adsorption capacity, <i>q</i><sub>m</sub>=91.82 mg/g was determined from the well fitted Langmuir plot compared with Freundlich and Temkin plots. Thermodynamic parameters such as free energy change (∆<i>G</i><sub>ads</sub>), enthalpy change (∆<i>H</i><sub>ads</sub>) and entropy change (∆<i>S</i><sub>ads</sub>) of adsorption were determined from adsorption equilibrium constants at different temperatures. The values of thermodynamic parameters revealed that the adsorption of EV on UBTL was feasible, spontaneous and endothermic in nature leading to chemisorption. Again, the equilibrium amount adsorbed, calculated from pseudo-second order kinetic plots for different initial pH of solution was found to be minimum at neutral medium compared with acidic and basic media due to the amphoteric nature of Ethyl violet in aqueous solution and zero point charge of pH of UBTL.
Highlights
Aquatic environment of developing countries are seriously polluted due to the rapid growth of dying, textile, ternary, paint/pigment, drugs industries
Prepared used black tea leave was characterized by Scanning Electron Microscope (SEM)
The present investigation explores the feasibility of used black tea leaves as a biosorbent to remediate Ethyl violet dye from aqueous solution in a batch process
Summary
Aquatic environment of developing countries are seriously polluted due to the rapid growth of dying, textile, ternary, paint/pigment, drugs industries. These industries are using synthetic dyes to color their products, and discharging a large amount of effluents into aquatic environment. Ethyl violet (EV) is a triphenylmethane dye which has extensive industrial applications [4]. To remove dyes from wastewater and refresh the ambiance, it is necessary to develop effective method for practical application. Can be used successfully to improve water quality by removing dye from wastewater. Several of these techniques have some kind of disadvantages.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
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 callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
