en تخصصي Special Original articles <p dir="ltr" style="text-align: justify;"><strong><em><span style="letter-spacing:.1pt;"><span style="font-family:times new roman,serif;"><span style="font-size:10.0pt;">Introduction:</span></span></span></em></strong><span style="letter-spacing:.1pt;"><span style="font-family:times new roman,serif;"><span style="font-size:10.0pt;"> Due to causing methemoglobinemia, different cancers, and teratogen effects in human nitrate contamination of water resources has become a critical environmental problem Therefore, the aim of this work was to determine the optimum condition of nitrate sorption onto magnetic nanoparticle.</span></span></span><br> <strong><em><span style="letter-spacing:.1pt;"><span style="font-family:times new roman,serif;"><span style="font-size:10.0pt;">Materials and Methods:</span></span></span></em></strong><span style="letter-spacing:.1pt;"><span style="font-family:times new roman,serif;"><span style="font-size:10.0pt;"> The removal of nitrate from aqueous solutions by magnetic nanoparticles has been studied through using batch adsorption method. X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), and Scanning Electron Microscopy (SEM) was applied to characterize the synthesized Fe₃O₄. The effect of pH, nano-magnetic, adsorbent dose, initial concentration of nitrate, and contact time were investigated.</span></span></span><br> <strong><em><span style="letter-spacing:.1pt;"><span style="font-family:times new roman,serif;"><span style="font-size:10.0pt;">Results:</span></span></span></em></strong><span style="letter-spacing:.1pt;"><span style="font-family:times new roman,serif;"><span style="font-size:10.0pt;"> According to SEM and TEM images, the adsorbent particles were nanosized and spheroidal; the sizes were about 20&ndash;30 nm. The experiments&#39; results indicated that the optimum adsorbent dose was 750 mg in 1000 ml of solution, with a contact time of 90 min, while the optimum pH was 9. The kinetic models for nitrate adsorption showed rapid sorption dynamics by both first-order kinetic (R² = 0.97) and second-order kinetic (R² = 0.96) models. Nitrate adsorption equilibrium data were fitted well to the Freundlich isotherm than Langmuir isotherm.</span></span></span><br> <strong><em><span style="letter-spacing:.1pt;"><span style="font-family:times new roman,serif;"><span style="font-size:10.0pt;">Conclusion:</span></span></span></em></strong><span style="letter-spacing:.1pt;"><span style="font-family:times new roman,serif;"><span style="font-size:10.0pt;"> The results showed that, magnetic nanoparticles can be used<br> as a low cost and efficient adsorbent for removal of nitrate from aqueous solutions</span></span></span><span style="font-family:times new roman,serif;"><span style="font-size:10.0pt;">.</span></span></p> Adsorption, Nitrate, Magnetite Nanoparticles, Kinetics 187 195 http://jehsd.ssu.ac.ir/browse.php?a_code=A-10-1-29&slc_lang=en&sid=1 Hamid Reza Pourzamani No Environment Research Center, Research Institute for Primordial Prevention of Non-communicable Disease, Isfahan University of Medical Sciences, Isfahan, Iran, and Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran. Nezamaddin Mengelīzadeh No Environment Research Committee, Isfahan University of Medical Sciences, Isfahan, Iran, and Student Research Committee and Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran. Mohammad Jalil jalil_6692@yahoo.com Yes Environment Research Committee, Isfahan University of Medical Sciences, Isfahan, Iran, and Student Research Committee and Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran. Zahra Moosavian No Department of Health, Isfahan University of Medical Sciences, Isfahan, Iran.