High and fast adsorption efficiency of simultaneous As+3, As+5 and F− by Al-doped magnetite synthesized via AACVD

Abstract We report the synthesis and characterization of Al-doped magnetite hollow spheres synthesized by aerosol assisted chemical vapor deposition. The microstructure of the nanoparticles was characterized by grazing incidence X-ray diffraction and transmission electron microscopy. Surface area determination was measured with Brunauer, Emmett y Teller method. Batch removal efficiency tests of As and F − ions were realized at three different contact times of 1, 10 and 15 min by contact with Al-doped magnetite nanoparticles with the As:F − solutions. After the exposure time elapsed, the solutions were immediately centrifuged to separate the nanoparticles. Subsequently, the decanted solution was analyzed by atomic absorption spectroscopy to determine the presence of As and Fe, and by the fluoride selective electrode technique to determine the F − ion. A high and fast As and F − adsorption efficiency was obtained. The adsorption capacity of the nanoparticles was determined and adsorption isotherms were calculated to determine the adsorption mechanism. The collected nanoparticles were analyzed by high resolution transmission electron microscopy to observe the presence of As:F − ions adsorbed on the surface. In addition, the presence of the species of As +3 and As +5 in the nanoparticles were analyzed by μ-X-ray fluorescence and μ-X-ray absorption near edge structure of As K-edge at the Stanford Synchrotron Radiation Lightsource.