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Abstract
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Heavy metals leaching can be reduced in soils with low adsorption properties using stabilizers. Our objective was to study the effect of zeolite, ZnO, and CuO nanoparticles on cadmium (Cd 2+ ), copper (Cu 2+ ), cobalt (Co 2+ ), nickel (Ni 2+ ), and zinc (Zn 2+ ) retention in a sandy loam soil using both repacked soil column and batch adsorption experiments. The stabilized soil samples for filling the column were prepared by adding 2% CuO, ZnO nanoparticles, and zeolite and were packed uniformly with a bulk density of 1.35 g cm –3 and were saturated with 0.01 M CaCl 2 before beginning the experiments. The columns were leached with a solution contains 50 mg l −1 Cd2+ , Cu 2+ , Co 2+ , Ni 2+ , and Zn 2+ . In comparison to the control, the retarda- tion factor value indicated that the addition of ZnO nanoparticles to the sandy loam soil had the greatest effect on decreasing the mobility of heavy metals, with the following trend: Cu 2+ > Co 2+ > Cd 2+ > Ni 2+ . The order of adsorption amount of the selected heavy metals under single adsorption conditions for all treatments was as follows: Cu2+ > Zn2+ > Ni2+ > Cd2+ > Co2+ , while in multi-component solutions, the highest sorption was found for Cu 2+ and Co 2+ , indicating that in both systems, stabilized soils had more adsorption capacity for Cu 2+ and Co 2+ than the control soil. It was observed that during both tests, the adsorption and retention of all selected heavy metals in nanoparticles stabilized soils were potentially high compared to zeolite stabilized soil.
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