Desorption Studies Of Magnetic Iron Oxide/Carbon Composite Materials For Pollutants In Water

In recent years,water pollution has become the main pollution problem of the world.Dyes bring huge economic benefits to people,but also produce a lot of dye wastewater that is harmful to the environment.If these wastewater are discharged into environmental waters without effective treatment,it will cause pollution of natural waters.The dyes used in the textile printing and dyeing industry can not only dye the water,but also prevent the reoxidation of water,block sunlight,cause damage to the environment,and thus interfere with the natural growth of aquatic organisms.In various dye removal technologies?such as chemical and electrochemical coagulation,flocculation,ion exchange,membrane separation,advanced oxidation processes,adsorption,photocatalysis and photooxidation?,the adsorption process shows great potential for the removal of dyes from wastewater.However,how to deal with dye-loaded adsorbents?desorption?is still a challenging problem1,In this work,a kind of Fe₃O₄/C adsorbent is prepared by a simple synthetic method called soaking-calcination.Activated carbon in adsorbent comes from household paper,which is easy to obtain and low cost.This absorbent has a certain adsorption capacity on methyl blue dye(8 mg g^-1).The result shows that the sample dispersed in the deionized water several times can make the solution acidic?pH?4?.When the adsorbent was used as a catalyst for the Fenton experiment,the process facilitated the release of dye molecules on the adsorbent,and to some extent inhibited the degradation of methyl blue by H₂O₂.And similar effects are obtained under different pH values and concentrations of methyl blue solution.Therefore,the Fenton reaction can be applied to the desorption of the adsorbent.In addition,the adsorbent has good recovery properties due to its magnetic prperties.2,In this study,AgCl,as a photocatalyst,can effectively degrade water organic dyes under the action of ultraviolet light.The composite material was formed by Fe₃O₄/C adsorbent and AgCl and methylene blue dye is adsorbed and photocatalyzed by Fe₃O₄/C/AgCl composite.The experimental results show that the incorporation of AgCl has no effect on the adsorption capacity(0.7 mg g^-1)of adsorbent.Take ultraviolet light irradiation after adsorption,Fe₃O₄/C/AgCl composite would continue to degrade methylene blue due to the presence of AgCl particles.New adsorption sites will be exposed on the surface of the adsorbent,so that the methylene blue dye will be re-adsorbed.Finally,the process reaches a new dynamic balance between adsorption and photocatalytic degradation.At the same time,due to the photosensitivity of AgCl,dye molecules on the surface of the adsorbent can be effectively degraded under uv irradiation.The photocatalytic effect is obvious and the fitting degree is 0.985.Fe₃O₄/C/AgCl can adsorb in the dark and degrade under ultraviolet light.