Research On Adsorption Of As(?) And Phosphorus In Water By Modified Metal Organic Framework Materials

As???is highly toxic?carcinogenic,teratogenic,and mutagenic?and seriously harms human health.Phosphorus pollution can cause eutrophication of water bodies and cause the death of aquatic animals and plants,resulting in a worsening water quality environment.Therefore,it is urgent to reduce the content of phosphorus and arsenic in the water body and save the water environment.The adsorption method is simple in operation,environmentally friendly and has high removal efficiency,and is one of the most promising water pollution treatment methods.The zirconium metal organic skeleton Ui O-66 has a strong stability due to its highly topological surface cubic structure.The surface is r ich in hydroxyl bonds and can be ligand-exchanged with metal ions and phosphate groups.The manganese oxide K-OMS-2 not only has a mild surface acidity and alkalinity,but also has an average valence of about 3.8.It has good redox properties and excellent ion exchange properties.However,the zirconium metal organic framework and manganese oxide are easy to stack and agglomerate,reducing their specific surface area and their active sites.In this study,the zirconium metal organic framework was used as a carrier,and the manganese oxide was modified by hydrothermal synthesis to prepare a nano-composite material K-OMS-2@Ui O-66.In this study,XRD,SEM,TEM,FT-IR,BET and XPS were used to characterize and analyze the synthesized K-OMS-2@Ui O-66 composite material.The characterization results proved K-OMS-2 Modified Ui O-66 successfully,and the evident core-shell structure could be observed.And the the average oxidation state of K-OMS-2@Ui O-66 is about 3.84,indicating that Mn?IV?,Mn???,and Mn?II?coexist in K-OMS-2@Ui O-66.K-OMS-2@Ui O-66 was used in the adsorption of As???.It has excellent adsorption performance in the p H range of 1.5 to 10.0.And it is easy to reach drinking water standards(? capacity of K-OMS-2@Ui O-66,were as high as 181.10 mg g^-1 at p H 2.0.Besides,the K-OMS-2@Ui O-66 showed good recycling capacity in the adsorption of As???.The mechanism analysis shows that the adsorption of As???may be through the synergistic effect of electrostatic attraction,oxidation,surface complexation and hydrogen bonding.K-OMS-2@Ui O-66 was used in the adsorption of phosphorus,and it showed good phosphorus adsorption performance at a p H of 2.0 to 8.0.At p H=4,the maximum adsorption capacity reached 83.72 mg.g^-1.In the adsorption of As???and phosphorus by K-OMS-2@Ui O-66,the adsorption process conforms to the pseudo-second-order kinetic model,indicating that chemical adsorption may dominate the adsorption process.The fitting effect of Freundlich isotherm model is obviously better than that using Langmuir isotherm fitting,which indicates that the adsorption process is a multi-layer adsorption,which occurs in a heterogeneous system.K-OMS-2@Ui O-66 shows excellent anti-interferencev in the adsorption of As???and phosphorus and is suitable for complex water bodies.K-OMS-2@Ui O-66 composite material has a good adsorption effect for both As???and phosphorus,and has a good application prospect.