摘要
Series of activated carbon(AC)modified MgFe-layered double hydroxides(LDH/ACs)were synthesized using ultrasonic-assisted co-precipitation method.Herein the mass ratio of Mg/Fe-LDH and AC was varied at 1.55,2.34,and 2.86,respectively.The calcinations of corresponding LDH/ACs were obtained at 723 K for 5 h and named as LDO-AC-1.55,LDO-AC-2.34 and LDO-AC-2.86,respectively.These products were characterized by Fourier transform infrared spectroscopy(FT-IR),X-ray diffraction(XRD),Brunauer-Emmett-Teller(BET)measurements and scanning electron microscopy(SEM).LDO-ACs were applied for the removal of methyl orange(MO).The result showed that aggregation degree of MgFe-LDH decreased in the existence of AC.The pore sizes of LDO-AC-1.55,LDO-AC-2.34 and LDO-AC-2.86 markedly increased with the sharp decreasing of surface area.The values of the statured adsorption capacity of LDO-AC-1.55,LDO-AC-2.34 and LDO-AC-2.86 were obviously higher than those of MgFe-layered double hydroxides fabricated by traditional method(LDO0).The mechanism for the enhanced adsorption may be that the loose macrospore structure of LDO-AC-1.55,LDO-AC-2.34 and LDO-AC-2.86 abbreviates the diffusion resistance and bore repulsive force of MO molecular coupled with its space confinement effect in contrast with LDO0,which is favor for the free self-assembly of MO to form intercalation compound.MO-loaded LDO-AC-2.34 was regenerated by calcination and reused several times,still retaining its original adsorption capacity.
基金
Supported by the National Natural Science Foundation of China(31201305)
the Natural Science Foundation of Shaanxi Province(2016JM2018)
