Preparation Of Magnetoplumbite Y-type Ferrite By Sol-gel Method And Study On Its Properties

In this paper,the preparation and adsorption of magnetoplumbite Y-type ferrite were studied mainly,and a composite material that porous zinc oxide coated magnetoplumbite Y-type ferrite was tried to prepare in order to improve the adsorption performance.The magnetoplumbite Y-type ferrite Ba₂Co₂Fe₁₂O₂₂ with rod-like and flaky mixed morphology was prepared by sol-gel method for the first time.The effects of pH value,calcination temperature,calcination time and heating rate on the crystal form of ferrite were investigated by X-ray diffraction?XRD?.The optimum conditions for the preparation of ferrite were determined.Scanning electron microscopy?SEM?analysis revealed that the magnetoplumbite Y-type ferrite prepared under these conditions was a mixed shape of rod and flaky.The ferrite prepared by optimum synthetic process was used to adsorb two kinds of different type's cationic dye?methylene blue?and anionic dye?congo red?.The effects of adsorption time,pH value,adsorbent amount and dye initial concentration on dye removal were elucidated.The main conclusions were as follows:When magnetoplumbite Y-type ferrite Ba₂Co₂Fe₁₂O₂₂ was prepared by sol-gel method,the optimum synthetic conditions were as follows:?1?The pH value of reaction system was 7,?2?The calcinating temperature was 1000?,?3?The calcinating time was 3 h,?4?The heating rate was 8?/min.Methylene blue?MB?was used as model cationic dye wastewater.The results of the adsorption experiments were as follows:Under these conditions that the room temperature was 293 K,the MB initial concentration was 10 mg/L,the pH was 8,the adsorption time was 21 h,the adsorbent amount of Ba₂Co₂Fe₁₂O₂₂ was 0.10 g,the MB removal rate up to93.95%,the equilibrium absorption capacity was 9.395 mg/g,the saturated adsorption capacity was 32.206 mg/g.The isothermal adsorption model corresponded well with the Langmuir isotherm;the dynamic adsorption model corresponded well with pseudo-second order kinetic equation.Ba₂Co₂Fe₁₂O₂₂ can be reused,after 4 times adsorption experiment,the MB removal rate was still 90.14%,its environmental performance was better.Congo red?CR?was used as model anionic dye wastewater.The results of the adsorption experiments were as follows:Under these conditions that the room temperature was 293 K,the CR initial concentration was 50 mg/L,the pH was 6,the adsorption time was 90 min,the adsorbent amount of Ba₂Co₂Fe₁₂O₂₂ was 0.15 g,the CR removal rate up to88.61%,the equilibrium absorption capacity up to 29.535 mg/g,the saturated adsorption capacity was 194.932 mg/g.The isothermal adsorption model corresponded well with the Langmuir isotherm;the dynamic adsorption model corresponded well with pseudo-second order kinetic equation.Ba₂Co₂Fe₁₂O₂₂ can be reused,after 4 times adsorption experiment,the CR removal rate was 85.93%,its environmental performance was better.Compared with the cationic dye adsorption experiment,the adsorption effect of Ba₂Co₂Fe₁₂O₂₂ on anionic dye wastewater was better.The porous ZnO and globular ZnO were prepared by the hydrothermal method.The results of the adsorption experiments were as follows:Under these conditions that the room temperature was 293 K,the MB initial concentration was 10 mg/L,the pH was 12,the adsorption time was 24 h,the adsorbent amount of ZnO was 0.10 g,the adsorption effect of porous ZnO on MB is better than globular ZnO,the MB removal rate up to92.10%,the equilibrium absorption capacity was 9.210 mg/g,the saturated adsorption capacity was 27.263 mg/g.The isothermal adsorption model corresponded well with the Langmuir isotherm;the dynamic adsorption model corresponded well with pseudo-second order kinetic equation.The magnetoplumbite Y-type ferrite Ba₂Co₂Fe₁₂O₂₂ was coated with porous ZnO for the first time,but not coated entirely,finally obtain material A.The material A was used to adsorb MB dye wastewater.The results of the adsorption experiments were as follows:Under these conditions that the room temperature was 293 K,the MB initial concentration was 10 mg/L,the pH was 10,the adsorption time was 21 h,the adsorbent amount of material A was 0.10 g,the MB removal rate up to 97.71%,the equilibrium absorption capacity was 9.771 mg/g,the saturated adsorption capacity was 30.874 mg/g.The isothermal adsorption model corresponded well with the Langmuir isotherm;the dynamic adsorption model corresponded well with pseudo-second order kinetic equation.Compared with the three kinds of adsorbent materials,it was found that the adsorption rate of the material A on MB was increased,but the adsorption property was not significantly improved,and its adsorption property was more inclined to Ba₂Co₂Fe₁₂O₂₂.