Graphene oxide/montmorillonite composite aerogel with slit-shaped pores: Selective removal of Cu2+ from wastewater

Abstract

Due to outstanding adsorption capacity, graphene oxide (GO) is widely considered as an auspicious material for metal ion separation to deal with water pollution. In this work, based on the stacking of GO and montmorillonite (MMT), as well as cross-link with sodium alginate (SA), aerogels with abundant slit-shaped pores is prepared to selectively adsorb Cu2+, noted as G/M/S aerogel. The results show that the prepared G/M/S aerogel is endowed with large specific surface area (266.3 m2 g−1) and high removal efficiency for Cu2+ (95.1 %), contributing by creating abundant slit-shaped pores that can selectively remove planar hydrated copper. Moreover, the competitive adsorption experiment is carried out with complex system of coexisting cationic, suggesting the adsorption order is Cu2+>>Zn2+>Mn2+>Cr3+>Cr6+. In addition, design of experiment (DOE) is carried out to reveal the effects of single factors on the adsorption of Cu2+ with G/M/S aerogel, confirming that pH>dosage>temperature>time. All the obtained results suggest that G/M/S aerogel could be considered as a kind of material with great potential to selectively remove Cu2+ from wastewater.