Preparation Of Wheat Straw Cellulose/Graphene Oxide Composite And Its Adsorption Research Of Cd(?) And Pb(?) In Water

At present,wheat straw is not fully utilized,and its direct effect on removing heavy metals in water is not good.Single wheat straw cellulose cannot be a good adsorbent material;graphene oxide has a good effect on heavy metal removal in water,but due to its price expensive,there are certain difficulties in promoting large-scale use.Wheat straw cellulose/graphene oxide composite material is a new material that combines the advantages of wheat straw cellulose and graphene oxide.It can broaden the use of wheat straw and solve the problem of insufficient utilization of wheat straw to some extent.The wheat straw cellulose/graphene oxide composite material can reduce the amount of graphene oxide on the basis of ensuring the good removal effect of heavy metals in water,so that the cost of removing heavy metals in water can be reduced,and the economy is guaranteed.In this paper,the cellulose in the wheat straw is extracted,then the graphene oxide is prepared by the Hummers method,and the wheat straw cellulose and graphene oxide are combined to prepare the wheat straw cellulose/graphene oxide composite material,and the same is used.To remove Cd2+ and Pb2+ from water.Firstly,the morphology of wheat straw cellulose,graphene oxide and wheat straw cellulose/graphene oxide composites were characterized by scanning electron microscopy(SEM),X-ray diffraction(XRD)and Fourier transform infrared spectroscopy(FTIR)..Secondly,wheat straw cellulose,graphene oxide,wheat straw cellulose/graphene oxide composite materials are considered to be positive for 5 factors and 4 levels in consideration of time,temperature,dosage,initial concentration and pH.The experiment was conducted to investigate the removal effect of each material on Cd2+ and Pb2+ in water,followed by single factor experiment on wheat straw cellulose/graphene oxide composite.Finally,the adsorption kinetics and adsorption isotherms of wheat straw cellulose/graphene oxide composites were studied,and the re-use effect was also investigated.The results showed that there were many particles on the surface of the wheat straw cellulose/graphene oxide composite,and the characteristic peaks also changed significantly.There were many oxygen-containing functional groups which were beneficial to remove heavy metals,indicating that the composite was successfully prepared and used in water.Removal of heavy metals is feasible.The removal rates of Cd2+ and Pb2+ in wheat straw were 69.02%and 63.77%,respectively.The removal rates of Cd2+ and Pb2+ in graphene were 93.53%and 88.47%,respectively.The wheat straw cellulose/graphene oxide composites The removal efficiency of Cd2+ and Pb2+ in water was the best,and the best removal rates were 99.22%and 93.25%,respectively.The single factor experiment further verified the conclusion.According to the fitting results of adsorption isotherm model,the adsorption of wheat straw/cellulose oxide composites on Cdluand Pb2+ in water and the Freundlich adsorption isotherm model are higher,and the correlation coefficients R2 are 0.9333 and 0.9489,respectively.The adsorption method was multi-layer adsorption,and the maximum adsorption capacity was 219.12 mg/g and 203.93 mg/g,respectively.The results of adsorption kinetics fitting were consistent with the quasi-second-order kinetic equation;wheat straw cellulose/graphite oxide After repeated use for 5 times,the removal rate of Cd2+ in water is still above 95%,and the removal rate of Pb2+ in water is above 85%,showing good reusability.