Activated graphene with fractal structure for the adsorption of malachite green with high removal rate

Abstract

In this study, the activated graphene (AG) was applied to remove a malachite green (MG) as an adsorbent. The AG with fractal structure was synthesized at high temperature under a nitrogen (N2) environment. The fractal structure is shaped like a branch that extends apart because the AG is created by the rGO with a thin sheet. The fractal structure allows AG to have a high surface area. The surface area of AG was found to be 1885.7 m2 g−1. Also, it makes many pores of micro, meso-size which improves the quality as compared to traditional activated carbon (AC). Due to these features, the maximum MG adsorption capacity was 791.27 mg L−1 within the contact time at 40 min. Freundlich isotherm and pseudo-second-order were fitted to AG. Moreover, after cleaning with ethanol and deionized water, the recycled AG maintained a 99.44% removal efficiency which suggesting a good reusability. The AG showed better adsorption capacity than commercial AC showing that AG could be utilized as an excellent adsorbent for next-generation owing to its high removal efficiency, eco-friendly nature, and the long-lasting ability for adsorption of MG. © 2021