Preparation Of Magnetic Fe₃O₄/Carbon Nanocomposites By Co-precipitation Method For Removal Of Copper Ions From Aqueous Solution

With the rapid development of semiconductor manufacturing,the treatment of liquid waste in the production process attracts increasingly attention of the industry.In this work,we use a modified coprecipitation method with SDS as dispersing agent to prepare three different Fe3O4/Carbon nanocomposites(Fe3O4@CNT,Fe3O4@GO and Fe3O4@AC),which are used to adsorb Cu2+.Phase,functional group,microstructure and magnetic performance of these adsorbents were systematically investigated.We also studied the influence of proportion between Fe3O4 and carbon on the adsorbing of Cu2+,as well as the resorption performance of these nanocomposites that desorbed by NaOH solution.(1)In this reaserch,we characterized the three different Fe3O4/Carbon nanocomposites by XRD,XPS and TGA methods,the result shows that the products prepared by modified coprecipitation method have a good purity and high productivity.Meanwhile,the result of magnetic property test shows that the absorbents can be separated from aqueous soulution easily by an applied magnetic field.The result of SEM shows that the SDS takes effect in dispersion of Fe3O4,and it has better dispersion with a little of Fe3O4 in adsorbent.(2)We analyzed the adsorption of these different Fe3O4/Carbon nanocomposites by different isothermal adsorption models,results of which show all of them coulid be fitted by the Freundlich,indicating that the multi-molecular layers adsorption could provide good description to the adsorption behavior.The maximal adsorption capacitys of Fe3O4@CNT,Fe3O4@GO and Fe3O4@AC can reach up to 9.48,32.49 and 21.10 mg g-1,respectively.Meanwhile,the analysis result also demonstrates that all of the adsorption of Cu2+ ion belong to ion exchange type,which is an endothermic and spontaneous process from the point of view of thermodynamics.(3)In this reaserch,the three different adsorbents are desorbed by NaOH solution(pH=11).After repeatedly readsorption experiments,the minimum decline of Fe3O4@CNT,Fe3O4@GO and Fe3O4@AC are calculated to be 12.7%,14.1%and 33.0%respectively.