The influence of silica functionalized with silanes on migration of heavy metals in soil

3-Mercaptopropyl-trimethoxysilane and [3-(2-aminoethylamino)propyl]trimethoxysilane were used to functionalize the surface of silica from Piotrowice in Poland to stabilize heavy metals (HMs) and arsenic in soil. The soil for the study was sampled from the impact zone of Głogów Copper Smelter and Refinery. The soil samples were exposed to five-step Tessier sequential extraction. The speciation studies were limited to five sequentially defined fractions in which metal content was determined. The addition of unmodified silica did not affect significantly the concentration of metals in individual fractions. Significant changes were noted upon introduction of functionalized silica in the soil. The hybrid formulations obtained significantly reduce the release of heavy metals and arsenic from soil sorption complex. The results indicate the potential use of functional formulations for reduction of metal migration in soil in the areas of exceeded concentration of heavy metals and arsenic in the soil, caused by industrial activity.