U(VI) adsorption onto covalent organic frameworks-TpPa-1

Covalent organic frameworks (COFs) represent an exciting new type of porous organic materials, which are constructed with organic building units via strong covalent bonds . Here in, the COF-2,4,6-Triformylphloroglucinol p-Phenylenediamine (COF-TpPa-1) was synthesized by solvothermal method for the removal of U(VI) from aqueous solution. Effects of pH, adsorption dose, contact time, uranium solution concentration, temperature and adsorption and desorption cycle on the efficiency of COF-TpPa-1 removal of U(VI) are investigated. SEM, XRD , TGA and FT-IR were employed to characterize the samples and analyze adsorption mechanism. The results manifested COF-TpPa-1 has the high adsorption capacity ( q m  = 152 mg/g), quick adsorption kinetic , high selectivity , outstanding recycle performance and good resistance to acids, bases and high temperature.