High-rate adsorption of acetaminophen from the contaminated water onto double-oxidized graphene oxide

• Double-oxidized graphene oxide (DGO) was prepared.
• Acetaminophen (ACT) adsorption of onto the DGO was examined.
• Efficient ACT adsorption obtained at neutral pH and low DGO concentration.
• High ACT adsorption capacity (704 mg/g) on DGO was achieved.
• DGO was found to be an efficient and promising adsorbent for pharmaceuticals.

A double-oxidized graphene oxide (DGO) was prepared and characterized. The DGO was the planar and layered sheets with the smooth surface with the BET specific surface area of 51.2 m2/g and an average pore size of 9.7 nm. A high density of oxygen-containing functional groups was developed on the surface of DGO. Adsorption of acetaminophen (ACT) was investigated on the prepared DGO. The maximum adsorption obtained at pH ⩽ 8. The experimental adsorption data was well fitted with the pseudo-second-order kinetic model. The Langmuir isotherm model had better fitness with the equilibrium adsorption results with the maximum adsorption capacity of 704 mg/g. Thermodynamic analysis indicated that adsorption of ACT onto DGO is a physical spontaneous and exothermic process. Accordingly, the DGO has a very high capacity for adsorption of pharmaceuticals from the contaminated water and can be considered as a promising alternative of conventional activated carbon adsorbent.