Enhanced adsorption of phthalic acid from aqueous solution by LDH@ ZIF-8 composites

摘要: LDH@ZIF-8 composite has been synthesized via in-situ growth of zeolitic imidazolate frameworks-8 (ZIF-8) on Zn/Al hydrotalcite. The morphology and composition of the samples were characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscope and N2 adsorption–desorption technics. The adsorption performances of LDH@ZIF-8 sample for phthalic acid were investigated. The results show that the adsorption capacity of LDH@ZIF-8 could be as high as 508.72 mg/g at 20°C, C0 = 100 mg/g. The adsorption isotherms and adsorption kinetics were well described by Freundlich isotherm model and the pseudo-first-order kinetic equation, respectively. In addition, recycling experiments revealed that the behavior of LDH@ZIF-8 is maintained after recycling for at least three times.