Facile Techniques to Synthesize Reduced Graphene Oxide for Removing Tetracycline From Water: Kinetics and Thermodynamics Studies

Abstract

In this study, reduced graphene oxide (rGO) was successfully produced from graphite precursor by chemical oxidation and exfoliation processes which were followed by a reduction process in mild conditions. rGO was then applied in the adsorption of tetracycline (TC) in water. SEM/EDX, XRD, FT-IR, BET, pHpzc were conducted to characterize the synthesized materials. The adsorption efficiency of TC from water was evaluated by changes in several factors such as contact time, temperature, pH of the solution, adsorbent load, and tetracycline concentration. Furthermore, adsorption kinetics, thermodynamics, and isotherms were also investigated. As the result, the adsorption process of TC onto rGO was spontaneous, endothermic, and governed by both physisorption and chemisorption. The maximum uptake calculated from Langmuir isotherm model was 58.03 mg/g. rGO material could be regenerated by using methanol and diluted NaOH solutions. The findings in this work provides a complete data on the TC adsorption process onto rGO and the process of recovery and reuse of rGO.