University of Tehran Press Iranian Journal of Soil and Water Research 2008-479X 50 2 2019 05 22 Effect of Nano and Micro TiO2 on Cadmium Stabilization in Soil Suspension in the Presence of Humic Acid Effect of Nano and Micro TiO2 on Cadmium Stabilization in Soil Suspension in the Presence of Humic Acid 449 462 70597 10.22059/ijswr.2018.254247.667870 FA Samaneh Aryabod PhD student of soil science, Faculty of agriculture, Ferdowsi university of Mashhad, Mashhad, Iran Amir Fotovat Associate Professor, Department of Soil Science, Faculty of agriculture, Ferdowsi university of Mashhad, Mashhad, Iran 0000-0002-5551-7002 Khorassani Reza Associate Professor, Department of Soil Science, Faculty of agriculture, Ferdowsi university of Mashhad, Mashhad, Iran Mohammad Hassan Entezari Professor, Department of Chemistry, Faculty of sciences, Ferdowsi university of Mashha, Mashhad, Iran Journal Article 2018 03 11 This study has investigated cadmium immobilization in the soil at the present of nano and micro titanium dioxid and the role of humic acid in nanoparticle stability and cadmium adsorption on nano and micro particles. The results of this study showed that in the soil contaminated with cadmium in suspension conditions, humic acid increased soluble cadmium in supernatant suspention and therfore increased cadmium availability in the soil. Modification of TiO₂ nanoparticles surfaces with humic acid increases adsorption of cadmium at the nanoparticle surfaces. Also, since microparticles have reduced the soluble cadmium in supernatant suspensions and the concentration of exchangeable cadmium to a greater extend than nanoparticles, it can be concluded that the effect of microparticles in reducing available cadmium in the soil is greater than that of nanoparticles. This study has investigated cadmium immobilization in the soil at the present of nano and micro titanium dioxid and the role of humic acid in nanoparticle stability and cadmium adsorption on nano and micro particles. The results of this study showed that in the soil contaminated with cadmium in suspension conditions, humic acid increased soluble cadmium in supernatant suspention and therfore increased cadmium availability in the soil. Modification of TiO₂ nanoparticles surfaces with humic acid increases adsorption of cadmium at the nanoparticle surfaces. Also, since microparticles have reduced the soluble cadmium in supernatant suspensions and the concentration of exchangeable cadmium to a greater extend than nanoparticles, it can be concluded that the effect of microparticles in reducing available cadmium in the soil is greater than that of nanoparticles. https://ijswr.ut.ac.ir/article_70597_fd7af0cd55c77c5d725633930a788880.pdf