Removal of uranium (VI) ions from aqueous solution by graphitic carbon nitride stabilized FeS nanoparticles

•Novel composite material of g-C3N4 decorated FeS was designed and prepared.•The adsorption capacity for U(VI) was 917.1 mg/g at pH = 6.0.•The adsorption isotherm for U(VI) was described by the Freundlich model. In this study, a novel graphitic carbon nitride decorated nanoscale FeS composite (g-C3N4/FeS) was prepared and performed for the removal of U(VI) in aqueous system. Results revealed that g-C3N4/FeS had excellent adsorbability, which can reach 917.1 mg/g at 303 K. In addition, the effects of pH, adsorbent dose, contact time and initial U(VI) concentration were investigated by batch experiments. Experimental results indicated the removal of U(VI) on g-C3N4/FeS was strongly dependent on pH, and the adsorption capacity reached the maximum at pH = 6.0. Kinetics studies under different conditions indicated the removal of U(VI) on g-C3N4/FeS fitted the pseudo-second-order model well. Furthermore, the adsorption isotherms of U(VI) on g-C3N4/FeS fitted with Freundlich models well. These results demonstrated that g-C3N4/FeS could be the promising alternative material for environmental remediation.