Cu-loaded reduced graphene oxide with ultrahigh adsorption performance for tetracycline from aqueous solution

Abstract

BackgroundThe elimination of antibiotics from wastewater has received extensive academic and social attentions since the increasingly antibiotic-related pollution posed fatal threat to aquatic ecosystem and public health. MethodHerein, a high-performance Cu-loaded reduced graphene oxide (C-rGO) was prepared via in-situ formation of Cu nanoparticle on graphene oxide (GO), which was subsequently applied to tetracycline (TC) removal. Significant FindingsIt was found that compared to the pristine rGO, the TC adsorption capacity of C-rGO was significantly enhanced, which could reach up to a record-high value of 3078 mg g-1. Adsorption kinetics and isotherms for TC onto C-rGO can be well-fitted by pseudo-first order kinetic model and Langmuir model, respectively. The ultrahigh TC adsorption capacity of C-rGO might be attributed to multi-interactions, i.e., π-π interaction, cation-π bonding, surface complexation, electrostatic interaction and hydrogen bond. In addition, the removal efficiency of C-rGO still kept relatively high level after being used for 4 cycles, illustrating outstanding recyclability of C-rGO. And C-rGO showed excellent adsorption capacities for other antibiotics, such as oxytetracycline, chlortetracycline hydrochloride, ciprofloxacin, sulfamethoxazole and norfloxacin. The ultrahigh TC adsorption ability and outstanding reusability highlighted its great application potential in the field of antibiotic-related wastewater treatment.