Efficient adsorption removal of tetracycline by layered carbon particles prepared from seaweed biomass

Seaweed Sargassum sp. has demonstrated its excellent adsorption capability for the removal of heavy metal ions. However, its potential application for the removal of organic pollutants is scarcely reported due to the organic leaching from the raw seaweed. In this research, layered carbon particles were prepared from seaweed Sargassum sp. and used for the adsorptive removal of tetracycline. Kinetic experiments indicated that an especially rapid uptake of tetracycline occurred and the removal percentage achieved 73.8% by 60 min. Though nonlinear fitting method failed to discern which kinetic model better fitted the experimental data, linear pseudo-second-order kinetic model was proved to better describe the adsorption kinetics than pseudo-first-order kinetic model, indicating the possible chemisorption of tetracycline on the carbon particles. Langmuir isotherm model simulated the adsorption isotherm data slightly better than Freundlich model. At 298 K, the maximum adsorption capacity of 278.4 mg/g for tetracycline uptake was obtained by Langmuir isotherm model. Both natural coexisting anions and humic acid could inhibit the uptake of tetracycline to some extent. These suggest that the layered carbon particles could be applied to the efficient removal of tetracycline from water. (c) 2016 American Institute of Chemical Engineers Environ Prog, 36: 59-65, 2017