Study On Removal Of Organical Pollutant With Application Of Magnetic Clay Minerals

Natural montmorillonite, a sort of layered aluminosilicate minerals, is in possession of swelling, intercalation and ion-exchange properties that make it comprehensive applications in various fields. Its interlayer areas have been applied excellent reactive sites. Inorgano-or organo-modified clay minerals can improve its physicochemical properties, such as specific surface area, hydrophilic and hydrophobic properties. However, the problems of efficient separation and recycling of clay materials and avoiding secondary pollution still exist. Therefore, it has been a challenge for researchers to develop new multifunctional clay mineral with high adsorption capacity, catalytic and magnetic properties.In this study, two kinds of surfactants were used as structural regulator to modify Fe-pillared clay mineral, and treated with acetic acid vapor prior to calcination for improving the magnetization of magnetically modified clay mineral. The preparation temperature was investigated as the key factor to tailor the structure of the modified clay mineral with addition of surfactant. XRD, FT-IR and VSM were used to characterize the magnetic clay minerals, and show that the co-pillar of Fe poly-ferric hydrate and surfactant can be intercalated into the montmorillonite interlayer. After treated in acetic acid vapor and calcinated at 500℃for 1h, the magnetic species ofγ-Fe2O3 nano-particles were transferred and anchored on the surface of the modified clay mineral with application of surfactant. The magnetization of modified clay mineral was improved significantly compared with the report from literatures, which provides the pre-requirement of separating the modified clay minerals from aqueous solution efficiently with application outfield magnet for reutilization.The performance of the magnetically modified clay mineral was evaluated by adsorption of 2,4-dichlorophenol. Ca.30-50% of 2,4-dichlorophenol could be removed with application of the magnetically modified clay mineral. After re-modified by hexadecyl trimethyl ammonium bromide (CTAB), the magnetic clay minerals present more than 20 percentage of removal efficiency of 2,4-dichlorophenol. Furthermore, the magnetic clay minerals can be intensified to separate easily and completely by external magnetic field.From this work, the magnetization of magnetic clay materials was improved significantly with application of surfactants as structural regulator to modify Fe-pillared clay. The magnetic specimens were just immobilized on the surface of clay layers, which keep the clay as an adsorbent and and magnetic separator. It can provide a good alternative to solve the problems of nanoparticles aggregation and separation. It is expected to possess comprehensive applications in environmental and chemical fields.