Determination of the behaviour of silver nanoparticles and Ag ions in organic-muck soil

The increasing presence of silver nanoparticles (AgNPs) in consumer products and their subsequent release into the environment raises concerns about their impact on soil and water systems. The present study investigates the interactions between silver nanoparticles and silver ions with organicmuck soil, with particular focus on their adsorption and retention mechanisms. Key physicochemical properties of the soil, including cation exchange capacity (CEC), specific surface area, and pH, were characterised to determine their influence on the behaviour of silver species. Adsorption experiments indicated that Ag+ ions were adsorbed more efficiently than AgNPs, with maximum adsorption capacities of 11.25 mg/g and 7.00 mg/g, respectively. The adsorption isotherms for both Ag+ and AgNPs fit the Freundlich model better than the Langmuir model, suggesting the presence of heterogeneous adsorption sites. Kinetic studies indicate that adsorption follows a pseudo-second-order model, implying chemisorption controlled by chemical interactions between silver species and the soil surface. Sequential extraction of silver species reveals that Ag+is more easily desorbed, while AgNPs are more tightly bound. These results highlight the environmental implications of silver nanoparticle contamination in soils and contribute to the understanding of the factors influencing the mobility and retention of silver in terrestrial ecosystems.

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Opracowanie rekordu ze środków MNiSW, umowa nr POPUL/SP/0154/2024/02 w ramach programu "Społeczna odpowiedzialność nauki II" - moduł: Popularyzacja nauki (2025).