Synthesis and Phosphate Removalof Ce/Mg-MOF-74

In this work, Ce doped Mg-MOF-74 with different Ce/Mg molar ratios was synthesized and characterized by X-ray diffraction, N 2 adsorption-desorption, scanning electron microscopy (SEM), and X-ray Photoelectron Spectroscopy (XPS).It was found that Ce/Mg-metal organic framework-74 (Ce/Mg-MOF-74) has an excellent capability to remove phosphate.The effects of different Ce/Mg molar ratios, crystallization temperature, pH, contact time, and the initial concentration of phosphorous solution on phosphate removal have been studied.Ce/Mg-MOF-74 with a Ce/Mg molar ratio of 1:2 achieved a maximum phosphate uptake capacity of 106.4 mg/g, which is much higher than that of Mg-MOF-74 (64.2 mg/g), Fe/Mg-MOF-74 (51.36 mg/g), and Ce-MOF (41.2 mg/g).The effect of the Ce/Mg molar ratio, crystallization temperature, initial concentrations of phosphate, contact time, and solution pH, on the adsorption of phosphate by Ce/Mg-MOF-74 was investigated.In addition, Ce/Mg-MOF-74 could be reused without significant loss of its adsorption performance after five cycles.