Efficient Removal Of Methylene Blue From Aqueous Solutions Using Magnetic Graphene Oxide Modified Zeolite

Nowadays,dye wastewater is one of most difficult industrial wastewater to be treated.Adsorption is considered as an efficient method to solve the wastewater owing to its simple operation and less land occupation.Zeolite,as a kind of absorbent,is not only environmental friendly,but also large in quantity and low in price.However,in the face of dye wastewater with complex composition,the adsorption quantity of dye onto single zeolite can not meet the requirements.In this paper,zeolite composites were prepared to purify dye wastewater.Cu²⁺ions were used as a coordination cation to bond zeolite to GO sheets by solid-state dispersion method to make magnetic zeolite composites with different GO content.The physical and chemical properties of Cu-Z-GO-M composites were analyzed by various characterization methods?SEM,XRD,VSM,FTIR,XPS and BET?,which can be used to provide theoretical basis for further analysis of the adsorption mechanism of MB onto magnetic graphene oxide modified zeolite composites?Cu-Z-GO-M?.A series of adsorption experiments were conducted to study the effects of different environmental factors,such as pH,temperature and ionic strength,on the removal of methylene blue by adsorbents.The results show that when pH>8,it is advantageous to remove MB by Cu-Z-GO-M?1:1?and so do the higher temperature.Additionally,the maximum adsorption quantity of MB onto Cu-Z-GO-M?1:1?is119.16 mg/g.The higher the concentration of NaCl in solution,the more inhibited the adsorption of MB by Cu-Z-GO-M?1:1?.The adsorption data were fitted by kinetic equation,isothermal adsorption model and thermodynamic eq uation respectively,indicating that the adsorption process of MB onto Cu-Z-GO-M?1:1?composite was satisfied with the second-kinetic model and Freundlich isothermal model.The adsorption behavior occurs on the surface of inhomogeneous substance.At the s ame time,the thermodynamic parameters show that the adsorption process is spontaneous and endothermic.In addition,the reusability of Cu-Z-GO-M?1:1?composite was investigated by desorption experiments.It was found that the removal efficiency of methylene blue remained at a relatively high level after five cycles of adsorption,indicating that the composite is with good reusability.On the one hand,it can reduce the secondary pollution of the composites to the solution,on the other hand,it can greatly reduce the adsorption cost.In this paper,the magnetic GO modified zeolite composite has good stability and good removal ability for MB.It is a promising absorbent and can provide some guidance for the research of composite adsorbent.