Author/Authors :
Karimi Pasandideh، Elahe نويسنده Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences , , Kakavandi، Babak نويسنده Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran , , Nasseri، Simin نويسنده 1Department of Environmental Health Engineering, School of Public Health and Institute for Environmental Research, Tehran University of Medical Sciences, Tehran, Iran , , Mahvi، Amir Hossein نويسنده Department of Environmental Health Engineering, School of Health; National Institute of Health Research; Center for Solid Waste Research, Institute fo , , Nabizadeh، Ramin نويسنده Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran , , Esrafili، Ali نويسنده Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran , , Rezaei Kalantary، Roshanak نويسنده Department of Environmental Health, School of Health, Tehran University of Medical Sciences, Tehran, Iran. Rezaei Kalantary, Roshanak
Abstract :
Background: In this work, the magnetite (Fe3O4) nanoparticles (MNPs) and silica-coated magnetite nanoparticles
(SMNPs) were synthesized as adsorbents for removing humic acid (HA) from water resources.
Methods: The adsorption processes were performed in batch experiments with which the influence of pH,
reaction time, adsorbent dosage, initial concentrations of HA and temperature were investigated. Specific
techniques were applied to characterize the features of both adsorbents (i. e. TECHNIQUES) (SEM, XRD, TEM,
BET, EDX and VSM).
Results: The maximum saturation magnetization for SMNPs was 30.2 emu/g, which made its separation from
the solution by a magnetic field to be easier and faster. The HA adsorption process onto the both adsorbents
were best described by the Freundlich isotherm and pseudo-second-order kinetic models. Highest adsorption
efficiency of HA by MNPs an d SMNPs occurred at acidic conditions (pH ? 3). The mechanisms of adsorption
process involved with a physisorption process such as (i. e. hydrogen bonding and electrostatic interaction).
The predicted maximum monolayer adsorption capacities obtained by Langmuir isotherm model for MNPs
and SMNPs were 96.15 and 196.07 mg/g, respectively.
Conclusion: Higher amount of HA adsorption onto the surfaces of SMNPs than MNPs surfaces was observed,
reflecting that silica impregnated on MNPs enhances the efficiency of the adsorbent in removing HA.
