Preparation And Adsorption Properties Of Iron Oxide Nanocomposites

In this work,Fe₃O₄@C,?-Fe₂O₃/?-AlOOH and Fe₃O₄ nano-adsorption were prepared by a template-free hydrothermal method.The obtained samples were characterized and the influence of the ratio of raw materials,reaction temperature and time for adsorption properties were also discussed.The details were summerized as followed:?1?Taking ferric chloride,cyclodextrin and urea as raw materials,Fe₃O₄ can be obtained when the experiment parameter was that the molar ratio of ferric chloride to urea was ranged from 1:0.75 to 1:6,adding amount of cyclodextrin was 3mmol,and temperature was at 200? for 12 h.As the molar ratio was 1:0.75,the specific surface area was23.07m²/g and the adsorption mass of Cr?VI?and Congo red is 10.06mg/g and 88.20mg/g.Taking ferric nitrate,cyclodextrin and urea as raw materials,Fe₃O₄ pure phase can be produced when the experiment parameter was that the molar ratio of ferric nitrate to cyclodextrin was ranged from1:0.15 to 1:2,adding amount of urea was 30 mmol,and temperature was at 200? for 12 h.As the molar ratio was 1:0.3,The specific surface area of core-shell structure Fe₃O₄@C is 112.91m²/g.Quasi-second-order kinetics model and Freundlich model can simulate the adsorption process of Congo red and Cr?VI?better,and the maximum adsorption capacity of Cr?VI?and Congo red was 33.35mg/g and262.72mg/g by calculation.?2?Taking ferric chloride,urea and glucose as raw materials,Fe₃O₄ pure phase can obtained when the experiment parameter was that the molar ratio of ferric chloride to urea was ranged from1:0.75 to 1:3,adding amount of glucose was 2 mmol,and temperature was at 200? for 12 h.As the molar ratio was 1:1.5,the product has an amorphous carbon structure and the specific surface area is 39.64m²/g,the adsorption capacity of Cr?VI?is12.69mg/g.Taking ferric nitrate,urea and glucose as raw materials,Fe₃O₄ phase can obtained when the experiment parameter was that the molar ratio of ferric nitrate to urea was ranged from1:0.75 to 1:3,adding amount of glucose was 2 mmol,and temperature was at 200? for 12 h.As the molar ratio was 1:1.5,the Cr?VI?adsorption mass of product reached 21.14mg/g and the specific surface area was 85.70m²/g.Fe3+ and partially reduced Fe2+are reacted to produce Fe₃O₄ particles under the action of mild precipitated ions OH-,then carbon of deposition was deposited on the surface of the particles,and the thickness of Fe2+ was increased to a certain extent,and finally forming core-shell structureFe₃O₄@C.?3?Taking ferric nitrate,aluminum nitrate and urea as raw materials,the effects of molar ratio of iron source/aluminum source and urea on the phase of the product was discussed.?-Fe₂O₃/?-AlOOH can be obtained when the experiment parameter was that the molar ratio of iron source to aluminum source was ranged from 1:0.33 to 1:4,adding amount of urea was 2.5 mmol,and temperature was at 180? for 12 h.As the molar ratio of iron source/aluminum source was 1:4,the Congo red adsorption was 99.66 mg/g.?4?Taking ferric nitrate,urea and CTAB as raw material,the influence of ferric nitrate content on the phase and adsorption properties of product was studied.Fe₃O₄ can obtained when the experiment parameter was that the molar ratio of ferric nitrate to urea was ranged from 1:0.25 to 1:1,adding amount of CTAB was 1.1mmol,and temperature was at 200?for 12 h.As the molar ratio of ferric nitrate and urea was 1:1,the Congo red adsorption mass of product reached 99.17mg/g.