Microwave-assisted spent black tea leaves as cost-effective and powerful green adsorbent for the efficient removal of Eriochrome black T from aqueous solutions

Publication date: June 2018Source: Egyptian Journal of Basic and Applied Sciences, Volume 5, Issue 2Author(s): Ayub Khan, Xiangke Wang, Kashif Gul, Fazli Khuda, Zaynab Aly, A.M. ElsemanAbstractIn this work, microwave-assisted spent black tea leaves (MASTL) were used as effective low-cost green adsorbents for the removal of Eriochrome Black T (EBT) from aqueous solutions and adequately characterized. The pHpzc of MASTL was found to be 4.6. The experimental conditions, such as pH, contact time, temperature, adsorbent dose and EBT concentration, were optimized to evaluate the interaction of EBT with MASTL. The adsorption isotherms were simulated by Langmuir, Freundlich, Temkin and Dubinin-Radushkevich models. The results showed that the Langmuir model best fitted the adsorption data. The monolayer adsorption capacity was calculated to be 242.72 mg/g at 25 °C. The thermodynamic data calculated from the temperature-dependent adsorption isotherms indicated that the adsorption process was spontaneous, endothermic and physicochemical in nature. The results revealed that the MASTL could be used as low-cost green adsorbents for the efficient removal of EBT from aqueous solutions in environmental pollution clean-up.Graphical abstract
Source: Egyptian Journal of Basic and Applied Sciences - Category: Science Source Type: research